# Full or fin keel?



## utchuckd

Can somebody pro/con a full vs. fin keel for a newbie (will learn to sail on said boat) and taking it thru the Caribbean? All I can seem to come up with so far is fin keel is better to the wind, and a full keel will protect your rudder.


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## jackdale

utchuckd said:


> Can somebody pro/con a full vs. fin keel for a newbie (will learn to sail on said boat) and taking it thru the Caribbean? All I can seem to come up with so far is fin keel is better to the wind, and a full keel will protect your rudder.


So far so good.

A full keel will generally track better dead down wind. Full keel boats tend to have a smaller draft allowing them to get into shallower water. But as you inferred, they do not tend to point as well as fin-keels. They also need more speed to get steerage way.


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## LManess

Well you might consider this.

Your keel is what keeps your boat from slipping sideways which is why full keel boats track better and so cruisers like them. Fin keels are better for racing because they allow for quicker turns.

If you want to cruise you also have to consider worse case scenarios. Like what happens when the wind is so severe that all sail must come down. In that case sometimes people have to put out drogs, not just to slow the boat but so that their boats will be quartered aft to the wind, which is recommended for heavy weather. On many full keel boats this position occurs naturally when in severe weather.

Linda


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## LManess

Oh, and I forgot one other advantage. If you are a cruiser with a full keel boat, you don't have to fiddle with your windvane as much as with a fin keeled boat.

Linda


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## Brent Swain

A full keel with bad hull balance wont track anywhere near as well as a fin keel with good hull balance. A boat travels many times the length of any keel in the time it takes to broach, so keel length has far less effect on tracking than one would assume. 
On a steel boat, a full keel means having an extra 400 lbs of dead weight in the stern , which aggravates hobby horsing, and is an inaccessible area , hard to maintain, and useless for a carrying any weight, being too far aft.


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## tdw

Linda,
To suggest that cruisers in general prefer full keels is simply not sustainable. Some do, no doubt but in this day and age a goodly number don't. Yesterday coming down the coast we passed an old gaff rigged, no doubt full keeled, schooner. Passed being the operative word and the Womboat is no greyhound. No thanks, not for me. I've owned and sailed both full and fin, albeit moderate fins and i'd not choose to go back to full. Otoh Bob Perry's Babas are fine boats as are Bill Crealock's efforts. Horses for courses as it were, the issue is not black and white.


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## Brent Swain

Trick is making sure your rudder and skeg are strong enough on a fin keeler, not hard to do, but often not done..


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## killarney_sailor

When I sit down with Mr Perry or another designer to have my ultimate cruising boat designed (yah, right!) I would ask for a conservative (longish) fin keel configuration. I think it is reasonable compromise.


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## jackdale

killarney_sailor said:


> When I sit down with Mr Perry or another designer to have my ultimate cruising boat designed (yah, right!) I would ask for a conservative (longish) fin keel configuration. I think it is reasonable compromise.


Some of Bill Creaclok's boats have a 3/4 keel as a compromise.


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## Faster

Bob Perry's Passports are similar.. one of these would be high on my list as a serious cruising boat:










BUT... this configuration does not 'back' much better than a full keel and for me, coastal cruising (frequent marina stops/unfamiliar docking situations, tight quarters anchoring, rafting) that's a bit of a deal breaker.

I don't feel, though, that it's necessary to go the full keel route for serious cruising but if you can handle the performance knock and the other characteristics, there are lots of very 'shippy looking' solid boats out there. For around here, though, give me my fin keel and spade rudder, thanks.....


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## killarney_sailor

Those are the sort of keels I was talking about. Mark Ellis has a number of interesting designs with long keels like these combined with big spade rudders - and don't bother giving the arguments about spade rudders and cruising I have heard them before.


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## jackdale

Ron 

Agreed

Full keel in reverse is no fun. Not just docking, but using a stern-tie.

I like a fin keel with a skeg rudder. Even then I have had rudder damage hitting a log off Powell River with that set up.

There is also the view that a full keel boat can be careened, while a keel cannot. I seen a photo of Bagheera, the Copeland's Bene 38 careened when they were doing rudder repairs. It probably depends on the boat.


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## poopdeckpappy

Then there's the best of both worlds, the _long keel _hull of a slocum 43


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## tdw

Fast.

This is the underwater profile of the M39. I find that she backs up pretty well providing you have the cojones to give her a bit of throttle. It can be a tadge alarming in close quarters but she is quite controllable. Mind you having a bow thruster as backup has made me less of a wee timorous beastie than I might otherwise be. 










Not, I must add as controllable as the fin and spade of Raven. She backed up like a car. Fast or slow, no worries.

Boat I had before Raven was full keel cutaway forefoot. Reverse ? Don't be silly.


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## tdw

btw ... in case anyone is thinking I was having a go at gaff rigged schooners, think again.

I seriously doubt we would go past this beauty ....










Bob Perry's Jakartan.

I would.


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## Rockter

I can certainly recommend the keel design on one of these....

UNION POLARIS 36 sailboat on sailboatdata.com

Very stable.

Perhaps not the highest-pointing ship in the sea, but you can't have everything.
.


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## Faster

tdw said:


> Fast.
> 
> This is the underwater profile of the M39. I find that she backs up pretty well providing you have the cojones to give her a bit of throttle. It can be a tadge alarming in close quarters but she is quite controllable. Mind you having a bow thruster as backup has made me less of a wee timorous beastie than I might otherwise be.


Kukka has a relatively narrow chord keel, and the rudder is more spade than skeg, esp with the proximity to the prop skeg section, I'm not surprised she backs up alright.. Nice compromise.

Of course you're planning to sell that bow thruster (spelled C-H-E-A-T-E-R) to some truly needy W32 owner, right?


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## MikeOReilly

The problem with this kind of binary question (full vs fin) is that this is only one of many design details which contribute to a sailboat's overall sailing & cruising characteristics. The _right answer_ will be as much dependent on the type of sailing you are planning (including crew considerations), as any single vessel characteristic. And no matter what, a poorly designed sailboat, no matter what the keel, will be a poor sailing vessel (although it might be a great live aboard).

I have owned both modified-fin (3/4 with skeg-hung rudder) and full keel cruising boats. I have also cruised fin keel, spade rudder cruisers. For my style of cruising I have currently settled on a full-keel traditional boat (Rafiki-37). The tracking ability makes it more forgiving, and I appreciate the ability to take a grounding with slightly greater comfort. But the negatives are significant: tight manoeuvring is very difficult and reversing is a crap shoot (I never know where I'm going to go).

Every boat is a compromise. The real trick is to understand what kind of sailor you are, and where/how you plan to sail. From there, you can start to make some rational decisions about keel and hull design, rig, size, material, equipment, aesthetics, and a hundred other factors.


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## Ladyslipper

A lot of added safety with a full keel and if your're cruising you won't be sailing up wind very often (aka BEATING); best part is you won't have to re-learn how to sail never having had a fin keel. And if you go with a double ender you'll be able to sleep at night during a blow. Downside may be a little speed in very light air and using more bottom paint.


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## PorFin

jackdale said:


> Ron
> 
> Full keel in reverse is no fun.


+1. We've got a full keel with a barn door rudder, and I'm here to tell you backing is ALWAYS an adventure. If there is absolutely no wind and no current, I can _usually_ know how the beast will track in reverse. Mostly it's all about using the throttle intermittently to balance prop walk with having the rudder pretty hard to starboard (the rudder imparts very little turning effort when in reverse.)

However, when conditions are not totally benign the old gal loves to make my life interesting. Doing the mental gymnastics thinking about the opposing forces keeps me on my toes, but usually I'm left with just getting her out into a fairway with enough maneuvering space to spin her until I get pointed in the right direction.

If there's a considerable cross wind or current, I've got to weigh the possibility of becoming a "bumper boat" against my desire/need to get underway.


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## sck5

Learn to dock with a full keel and everything else will seem easy after that!

I first learned to dock on an Island Packet. Now I have a Caliber which has a longish keel and a skeg hung rudder. Seems way easier.


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## jackdale

sck5 said:


> Learn to dock with a full keel and everything else will seem easy after that!
> 
> I first learned to dock on an Island Packet. Now I have a Caliber which has a longish keel and a skeg hung rudder. Seems way easier.


After skiing the black runs, the blue runs are easier too.


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## MikeOReilly

sck5 said:


> Learn to dock with a full keel and everything else will seem easy after that!


Agreed!

Actually, this is what I was trying to get at with my comments. Knowing something about your sailing/cruising plans will help with your choice of boat (and keel). If my cruising was mostly about marina-hopping, then I would definitely NOT want a full-keel boat -- especially not in the Med


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## jackdale

MikeOReilly said:


> Agreed!
> 
> Actually, this is what I was trying to get at with my comments. Knowing something about your sailing/cruising plans will help with your choice of boat (and keel). If my cruising was mostly about marina-hopping, then I would definitely NOT want a full-keel boat -- especially not in the Med


Mike

While the standard Med moor to stern-to, I learned to do mine bow-in with a stern anchor. Much easier and more privacy. Having a U-shaped pulpit helps.


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## MikeOReilly

jackdale said:


> While the standard Med moor to stern-to, I learned to do mine bow-in with a stern anchor. Much easier and more privacy. Having a U-shaped pulpit helps.


That's good to know Jackdale. I love my Rafiki. It's a wonderful cruising boat for a short-handed crew, but I'd rather take on Force 9 gale than face a tight marina .


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## dacap06

A keel is your underwater wing, just like your sail is the in-air wing. Remember, the sails generate lift around the leeward side of the airfoil, the angle of the boat as it moves through the water causes the keels to generate lift on the windward side of the waterfoil. The vector sum of these forces is what pushes you forward. As I understand it, the advantages and disadvantages are as follows.

A full keel is flat and has a lot of wetted surface to cause friction. They are generally slower and don't generate lift at all. Instead of producing lift they simply provide resistance to sliding directly downwind, which the wind would otherwise blow you. Full keels typically don't go as well to weather as other designs. On the other hand, the draft is shallow and damage is light to non-existent when the boat is run aground. Full keels are very traditional and tend to be very strong too. That's why they are used most often on blue water cruisers where speed is less important than standing up to a harsh environment. They can make maneuvering difficult, especially if the prop is in an aperture.

Fin keels are shaped much more like an airplane wing and do provide lift. The most efficient kind is the high aspect keel. They are narrow and deep and are efficient for the same reason a sailplane's wing is. Because they generate lift, they don't need to be so big -- and so they have less wetter surface and less friction (read fastest). They also put the lead ballast down the farthest, which moves the Vertical Center of Gravity (VCG) down the lowest. That gives you the best righting arm moment to keep the boat more vertical for a given weight. The high-aspect keel also goes to weather the best, but it is the most easily damaged upon grounding, and since it is the deepest draft it is the most likely type to touch ground. Needless to say, you can't get into shallow areas with a deep, fixed keel.

Low aspect fin keels are a compromise. This kind of keel is the shoal draft keel and is the best kind to have where I sail. They are very popular here in the Chesapeake Bay and along the Bahamas, simply because the water is so shallow. Low aspect fin keels don't generate as much lift since the wing chord is stretched longer. And because they don't generate as much lift, they don't go to weather as well and they also have to be bigger, so there is more wetted surface to cause friction. VCG is not as low so they require more ballast. therefore making the boat heavier.

There are a lot of variations on keels -- the full keel with cutaway forefoot. The shoal keel with bulb. The shoal keel with wings. The bulb at the end of the high aspect keel. The lifting high aspect keel. The keel stub with a swinging centerboard, and many more. All have advantages, disadvantages, and some have maintenance actions you need to accomplish every so often. Which kind is best for you depends on the kind of sailing you hope to do and the depth of water you want to get into.

Several before me have spoken about tracking, so I won't cover that.

Hope this helps!

Tom


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## -OvO-

Thanks Tom, that was very informative.



> Which kind is best for you depends on the kind of sailing you hope to do and the depth of water you want to get into.


I'm currently shopping, but I haven't sailed anything but fin keels and centerboards, so I'd like to know more about these other kinds of keels. I'm having a tough time deciding and am afraid I'm going to wind up buying one of each.


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## JimPendoley

While the prop in the aperture makes backing up an adventure on my full keel attached rudder Vanguard, it makes sailing through a field of lobster pots a lot less stressful. Have never snagged a pot in 20 years of sailing in Maine-I don't even try to dodge them. I'd not want to snag a pot line at 2AM with a spade rudder or foul one on my exposed prop. Most trap lines have many weighted pots attached, very easily could bend a rudder post or prop shaft. Hitting a ledge with a fin keeler even at slow speed could sink your vessel a lot easier than it would a full or 3/4 keel boat.


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## sneuman

PorFin said:


> +1. We've got a full keel with a barn door rudder, and I'm here to tell you backing is ALWAYS an adventure. If there is absolutely no wind and no current, I can _usually_ know how the beast will track in reverse. Mostly it's all about using the throttle intermittently to balance prop walk with having the rudder pretty hard to starboard (the rudder imparts very little turning effort when in reverse.)
> 
> However, when conditions are not totally benign the old gal loves to make my life interesting. Doing the mental gymnastics thinking about the opposing forces keeps me on my toes, but usually I'm left with just getting her out into a fairway with enough maneuvering space to spin her until I get pointed in the right direction.
> 
> If there's a considerable cross wind or current, I've got to weigh the possibility of becoming a "bumper boat" against my desire/need to get underway.


+2 backing is a b***h. But I keep telling myself, the boat was designed to go in the _other_ direction!


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## CapnBilll

MikeOReilly said:


> That's good to know Jackdale. I love my Rafiki. It's a wonderful cruising boat for a short-handed crew, but I'd rather take on Force 9 gale than face a tight marina .


Of course that is kinda what it was designed for. :thumbs up:


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## MikeOReilly

CapnBilll said:


> Of course that is kinda what it was designed for. :thumbs up:


YUP 

Our Rafiki loves it when it blows.


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## travlin-easy

I did a lot of research on keel designs for cruisers over the past couple of years, and the conclusion I came up with was verified in books on cruising by Lin and Larry Pardey, Capable Cruiser and Storm Tactics.

First and foremost, at age 71 I'm not what some would refer to as a seasoned sailing captain, however, I've owned 16 powerboats and been on the water since age 5. I've only been sailing for the past 7 years, with an average of 45 trips per season. I've only owned two sailboats, a fin-keeled Catalina 27 and a full-keeled 33 Morgan Out Island and most of the time I sail single-handed.

One of the primary benefits Lin and Larry pointed out in their books was in the likely event you strike an immovable or nearly immovable object with your keel, the fin keel would likely incur more damage to both the keel and other parts of the hull than a full-keeled boat, which would likely slide more gently onto the object. Additionally, the rudder would probably not incur damage on the full-keeled boat because the rudder would be somewhat protected by the keel, whereas the fin-keeled boat would likely be subject to rudder damage under these circumstances.

In my case, often when sailing at night in Chesapeake Bay, crab pot markers tended to slide down the length of the full keel without snagging the rudder or prop. When I sailed the Catalina at night I could almost count on snagging at least one crab-pot marker, and some nights up to a half-dozen in a 20-mile trip along the channel edge.

I've been caught in some nasty storms with both boats and unequivocally the Morgan with the full keel handled far better in a quartering, following sea than the Catalina. The Catalina was much more tender to wind gusts, while the Morgan just kept plodding along at the same speed. 

Now, the Fin-keeled Catalina pointed a bit better than the full-keeled Morgan, but not significantly better--maybe a couple degrees at best. As for the speed, both are relatively fast, which was surprising to me because everyone told me the Morgan would really be slow--even in a 10-knot wind. 

When I purchased the Morgan I was also looking at several other boats in the same price range and similar size. However, the only one with a full-keel was the Morgan and having sailed the boat for one season I believe the choice I made was sound, especially for blue-water cruising. I'll be heading south from Chesapeake Bay to the Florida Keys, Dry Tortugas and across to the Bahamas this coming fall and I'm confident the Morgan with its full keel and wide beam will handle the task with ease.

Good Luck,

Gary


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## Rockter

*Travelineasy :*

On my own ship, a Union Polaris 36, for me, there is no substiture for the full (or near-full) keel.

In summer, in lighter airs, most of the other ships pass me easily.

But you wait for when things get rough, in the bigger seas, particularly long hours in the bigger seas.

It is different then.
.


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## Faster

Different horses for different courses... There's no right or wrong answer here.

As has been mentioned already, perhaps numerous times this decision is going to come down to the type of sailing you do, the area you sail in, the performance level that 'turns you on', etc etc....

If a full keel was really the absolute optimum for offshore sailing we'd still see the Suhali's on the Volvo Ocean Race. (and I imagine a few of those crew, crawling soaking wet into an equally wet berth might well wish they'd chosen that ride from time to time)

For our type of sailing fin/spade suits us fine. Were we going offshore we'd probably choose a middle of the road compromise, with Perry's Passport 40 being at the top of the list..

But there's also no denying the "Aaarrgh" appeal of the heavily teaked up, massive tillered, rock solid, bowspritted, cutter rigged rugged cruisers like the Baba's and Westsails and so many others.. clearly there's a demand for those too.

So let us fin keelers have our day on that light air beat... you'll get your chuckle when it dusts up to 30 knots and you're finally leaving us in the dust...or at least looking a bit more comfortable as we sail alongside...

It's ALL good...


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## Jeff_H

I apologize that this is very long primarily because it was written years ago for another purpose but it does broadly address issues associated with selecting a keel type. In reality, as quite a few posts above have suggested, boats behave as systems, and there is no one universally right answer on any of these broad questions. 

"Your question seems to be about appendages. In principle Appendages keep a boat from making leeway. They come in many shapes and sizes. Keels are supposed to be a fixed appendage and centerboards generically are moveable appendages that occur on the centerline but centerboards are just one kind of moveable appendage. In more detail:

Keels:
The earliest form of a keel was simply the backbone of the boat extending through the bottom planking. (Like a Viking ship) That works OK with running and reaching sails but when you try to point toward the wind you slip side wards at great speed. As sails and rigs were invented that allowed boats to point toward the wind the keel was extended below the boat either by planking the hull down to a deeper backbone or by adding dead wood (solid timber below the backbone. A planked down keel permitted the space between the planking to be filled with heavy material (originally stone), which served as ballast keeping the boat from heeling. After a while it was discovered that there were advantages to bolting a high-density cast metal ballast to the outside of the deadwood and interior ballast dropped out of fashion. 

Full keels:
These earliest keels pretty much ran from the point of entry at the bow, to the aft most point of exit at the stern. Those are full keels in the fullest sense of the word. 

They have some advantages; the keel theoretically forms a long straight plane, which keeps a boat on course better (greater directional or longitudinal stability). If you run aground they spread out the load over a larger area reducing the likelihood of damage. Once really planted they keep the boat from tipping over fore and aft. They are easier to haul and work on. You can spread out the ballast over a longer distance and so they can be shallower for the same stability. You have a greater length to bolt on ballast so it is a theoretically sturdier and simpler connection. You often hear that the rudder is better protected on a full keel, but that is not usually the case. On most fin keel boats, the rudder is designed with a significantly shallower draft so that even if the keels hit bottom, the rudder doesn't. But generally, the rudder on a full keeled boat is only inches from the bottom of the keel placing it at greater risk. Repair yards here on the Chesapeake talked about the frequency with which Island Packet came in with damaged rudders. In their case, this was a post hung rudder as deep as the keel, which is an example of a worst of all worlds solution. 

Full Keels have some disadvantages; a larger portion of the keel operates near the surface and near the intersection of the hull and keel, which are both turbulent zones. They also have comparatively small leading edges, and the leading edge is the primary generator of lift preventing sideslip. Because of that they need a lot more surface area to generate the same lift. Surface area equates to drag so they need more sail area to achieve the same speed. Long keels tend to be less efficient in terms of lift to drag for other reasons as well. As a boat makes leeway water slips off of the high-pressure side of the keel to the low-pressure side of the keel and creates a turbulent swirl know as a tip vortex. This is drawn behind the boat creating drag in a number of ways. The longer the keel, the bigger the vortex, the greater the drag. So they need more sail area again to overcome this drag. To stand up to this greater sail area the boat needs more ballast and a stronger structure, which is why long keelboats are often heavier, as well. (Of course, then the spiral starts again as more sail area is needed to overcome that additional weight as well. It is the classic weight breeding more weight design cycle) Full keels tend to be much less maneuverable, especially under power. 

Fin keels:
By the classic definition of a fin keel, now out of vogue, any keel whose bottom is less than 50% of the length of the boat is a fin keel. Fin keels came into being in an effort to reduce drag. Cut away the forefoot or rake the stem, as well as, move the rudderpost forward and rake it sharply and pretty soon you have a fin keel. Today, there seems to be a widely accepted belief that a fin keel implies a separated rudder (skeg hung or spade) but in fact early fin keels usually had their rudder attached. No matter what we call them, these comparatively short keels with attached rudders were in all ways 'a worst of all worlds situation'. They offer all of the disadvantages of both full and fin keels, but with nearly none of the virtues of either. Unknowing or unscrupulous brokers will often refer to boats with fin (or near fin) keels as full keel if they have an attached rudder. 

Fin keels with separate rudders seem to be the most commonly produced keel form in the US these days. (I could be wrong, there is a slight resurgence of full keels these days)

Fin keels have some advantages as well. They have less drag as explained above so they typically make less leeway and go faster. You can get the ballast down lower so in theory they are more stable for their weight. They are more maneuverable. They take better advantage of the high efficiency of modern sail plans and materials. They work especially well in terms of roll dampening and so offer advantages in terms of motion comfort. 

They have some disadvantages as well, many of these have been offset or worked around by modern technology but at some level they are still accurate critiques. They often have less directional stability than long keel boats so the tend to wander more under sail. Since directional stability is also a product of the dynamic balance between the sail plan and underbody, in practice they may actually hold a course as well as a full keel. In general though you can expect to make more course adjustments with a fin keel. It is sometimes argued that the lower helm loads requires less energy to make these corrections so a fin keel may also require less energy to maintain course. This I think is a product of the individual boat and could lead to a debate harder to prove than the number of angels that can dance on the head of a pin. 

Fin keels are harder to engineer to withstand a hard grounding and when aground they are more likely to flop over on their bow or stern. (Although in 40 plus years of sailing, I have never heard of anyone actually experiencing this.) Fins typically have deeper draft. They are easier to pivot around and get off in a simple grounding. 

Shoal keel
A shoal keel is just a keel that is not as deep as a deep keel. Today the term seems to be applied mostly to shallow fin keels. Shallow full keels seem to be referred to as shoal draft boats. A shallow fin is a tough animal to classify. Like a fin keel with an attached rudder, I really think it has few of the advantages of either a deep fin or a full keel and has many of the worst traits of both full and fin. This can be partially offset by combining a shallow fin with a centerboard, which is a neat set up for shoal draft cruising.

Bulb Keel:
A lot can be done to improve a shallow fin. One way is to add a bulb. A bulb is a cast metal ballast attachment added to the bottom of the keel. They concentrate the ballast lower providing greater stability and sail carrying ability than a simple shallow keel. Traditionally bulbs were torpedo or teardrop shaped. They have been re-contoured to provide some hydrodynamic properties. Recalling the discussion on tip vortex from above. Shallow keels need to be longer horizontally than a deeper fin in order to get enough area to prevent leeway. This means that a shallow longer fin would generate more tip vortex and more drag than a deeper keel. The bulb creates a surface to turn the water aft and prevent it from slipping over the tip of the keel thereby reducing tip vortex. This does not come free since a bulb increases frontal area and surface area. 

Scheel Keel:
Scheel Keels are a specialized form of shoal bulb keel which is shaped to reduce induced drag (tip vortex) and surface area, and lower the center of gravity. Like any shoal bulb keel ity offers a very big improvement over a simple shoal draft fin but do not sail as well as a properly designed deeper fin. 

Wing keels 
Wing keels are a specialized type of bulb keel. Instead of a torpedo shaped bulb there are small lead wings more or less perpendicular to the keel. These concentrate weight lower like a bulb and properly designed they also can useful in reducing tip vortex. There has been some discussion that wings increase the effective span of the keel when heeled over but this does not seem to be born out in tank testing of the short wings currently being used in production sailboats. Not all wings are created equal. They potentially offer a lot of advantages, but they are heavily dependent on the quality of the design and I really think that many wing designs are not really working to their potential. 

Then there is the whole grounding issue. The popular perception is that wing keels are harder to free is accurate. This seems to be born out by discussions that I have had with towboat skippers on the Chesapeake. According to them wing keels were extremely harder to free. Straight fins were much easier to free, especially when heeled. There also is some evidence that bulbs may also be easier to free than fin keels.

Keels that are not really keels:
Swing keels are ballasted centerboards and drop keels are ballasted daggerboards that are ballasted beyond what it takes to submerge themselves. They are really forms of centerboards. More on these in the discussion on centerboards.

Keels that are keels that move.
I said in the introduction that keels do not move. That used to be true. We now have canting keels, which can be pivoted from side to side. They are best designed to be light fins with heavy bulbs that can be canted to windward increasing the effectiveness of the righting aspects of the keel. Just one problem, a keel canted to windward losses efficiency to prevent leeway so they really need other foils to keep leeway in check. I frankly do not like the idea of a canting keel. I think canting keels are too complex and potentially problematic to find general useage in daysailers and cruisers. 

Centerboards:
Centerboards are appendages that can be raised and lowered on or near the centerline of the boat. They can rotate up into a trunk or rotate below the boat. Daggerboards are a type of centerboard that raises vertically or near vertically in a trunk. Swing keels are a type of rotating centerboard that actually contains a substantial portion of the boat’s ballast. They may be housed in a trunk like a Tartan 27 or 34 or hung below the boat like a Catalina 22. In the case of the Tartan 27 or 34 they are more frequently referred to as a Keel/ Centerboard (abbreviated k/cb). A swing keel is intended to act as a fin keel when lowered and allow some sailing in the partially raised position. My biggest problem with swing keels is that most do not have a positive lock down. In an extreme knockdown they can slam up into the hull greatly reducing the boat’s stability. This is a pretty rare occurrence and usually requires big wave action combined with a lot of wind, but I have experienced it out in the Atlantic. 

A drop keel is a daggerboard that actually contains a substantial portion of the boat’s ballast. These are easier to lock down but can be more easily damaged in a grounding. They generally have better shape than a swing keel and can be more robust, but not always are. 

Other appendages: (besides the rudders)
Bilge keels (or twin keels for our English friends) are a pair of keels (usually fins these days) that emerge on either side of the boat and angle out. They offer some advantages. If you let the boat dry out the boat can stand on the two keels and wait the next tide. There are dubious theories about increased efficiency since one is vertical like a good leeway resisting foil and one is canted like a good stability inducing foil. With computer modeling there has been greater success in approaching that theory on large bilge keel boats. While bilge keels do allow shallow draft though, they extremely difficult to free once aground since having the two keels on the ground prevents heeling the boat to get free. In practice bilge keels have enormous wetted surface creating a lot of drag at lower speeds, and produce two very large tip vortexes creating a lot of drag at speed. 

Keel- Centerboards are a wonderful choice for coastal and offshore cruising. Properly designed they offer nearly the performance of a fin keel, and yet permit access to shallower venues. They can be partially raised to precisely control the center of lateral resistance and therefore offers the ability to have a very neutral helm and great tracking in a wide range of conditions. Properly constructed they have proven to have a long service life. Keel-centerboard boats really proved themselves offshore during the late 1950’s and into 1960’s.They fell out of popularity with the advent of the wing keel in the early 1980’s. The downside is that they are a little harder to maintain, and because the ballast is closer to the center of buoyancy they require more ballast and so end up requiring a higher overall displacement, a higher ballast to displacement ratio, or are more tender, or some combination of the three. 

Bilge boards (for the scow guys), are a pair of centerboards that angle out of each side of the boat. They work well on scows but I’ve never been able to really figure out scows anyway. Seriously, You raise the windward board and lower the Leeward one on each tack and because they are close to vertical they can be small and efficient. I still don’t get the scow thing.

Last but not least- Leeboards. Leeboards are foils that are bolted to the side of the hull like on Dutch Jachts and Herreshoff Meadowlarks. Phil Bolger’s sharpies use them a lot as well. They have some advantages but they drive me nuts. They are vulnerable in docking and ideally are raised and lowered on each tack also. Some are designed to hinge outward from the hull so as to feather and so those do not need to be raised.

So that’s about it. The final is tomorrow- multiple choice and essay.

Jeff


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## Ajax_MD

One of my dockmates has a Cape Dory 30. This thread has got me curious, so I'll see if I can con him into taking me out when the wind is honking.

I've had my Pearson 30 out in the mid 20's and was quite comfortable. I've done two mid-length night races, and a couple of night cruises and found that the best way to avoid the crab pots was just to find deeper water. The Martec folding prop doesn't hurt either.

I fully believe that full keels have certain advantages, but it just doesn't blow hard enough, for long enough here on the Chesapeake to make me want one.


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## jackdale

Jeff - great post as usual. 

I used up a repudiation point on something else. So I can only give you a Like.


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## Jeff_H

jackdale said:


> Jeff - great post as usual.
> 
> I used up a repudiation point on something else. So I can only give you a Like.


Jack,

Thank you for the kind words...

Jeff

One thing that my article does not address is the perception that somehow a full keel adds stability or improves motion comfort. In and of itself, a full keel does neither and in many cases the full keel actually works against either. 
Much of that perception comes from the fact that Full keels are often associated with vessels whose design lends itself to high stability or a gentle motion, but in some ways the greater sail area required to over come the higher drag means that a full keeled boat may actually have less useful stability, and so sail at greater heel angles. Similarly the heavier rigs and round bottoms associated with full keel type forms, often mean a roller motion.


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## jackdale

As I tell my students when they ask these types of questions, 

"All boat designs are compromises, and the worst one is ..."


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## travlin-easy

I'm not sure about that, Jeff. My Morgan doesn't heel much at all, even when the winds are really nasty. I'm guessing that it may be a combination of things, including the extra-wide beam, plus a real heavy, full-keel that keeps the boat upright.

Gary


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## Jeff_H

In the case of your Morgan OI 33, if she does not appear to heel much it is as a result of whole bunch of reasons which have very little do with the type of keel that she has or the fact that she has a comparartively low-ballast to displacement ratio for a shoal draft boat. 

In the case of the Morgan 33, these are very beamy boats, with small sail plans for their displacement. They also have a lot of freeboard so that the heel angle does not seem all that extreme since the rail remains high above the water at pretty large heel angles. In fairness though, designers like Charlie Morgan, Ted Hood, and Dieter Empachter were all able to model comparatively heavish displacement designs that are less drag than might otherwise be expected. Hood and Empachter, made up for the extra displacement with comparatively high ballast ratios and generous sail plans.....Morgan on the Out Island series, not so much.


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## travlin-easy

Thanks Jeff. I'm old, but I'm still learning more about sailing every day, thanks in a large part to the Sailnet.

Cheers,

Gary


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## PCP

Not referring to centerboarders or swinging keels that are a particular case it is clear to me that the design of keels and the way they carry the ballast have suffered a technical big evolution on the last 40 years of the XX century, evolution made possible by new materials, new building techniques and computerized hydrodynamic analysis of hulls, keels and ruder and their behavior.

If it is true that a full keel has some advantages over a well designed fin keel it also true that the some of advantages that a fin keel brings makes its use more appropriated in almost all situations and the way the hull, keel and ruder design have evolved on the last 50 years are a proof of that.

Even in what concerns bluewater boats that is very evident. We can pick Halberg-Rassy, Najad, Malo or any other blue water cruising boat that is not made over a 30 or 40 year's old designs, but whose designs have been modified through the years to bring to the same initial program that lead to their design 50 years ago (blue water cruising), all the advantages and benefits that modern design and new materials and technologies permit.

Since Andrews have posted already a drawing of a Malo design from the 90's we can have a look at the Malo hull, Keel and ruder evolution through the last decades (the results with Halberg-Rassy or Najad would be similar):

*From the 70's:*










*From the 80's:*










*From the 90's:*



















*Already from this century:*










Regards

Paulo


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## paul323

Jeff - idle curiosity - you didn't mention twin keels. I remember seeing these in the UK, where in areas with a large tidal range and shallow water you could see many smaller boats standing up high and dry, sitting happily on their twin keels, at low tide. I read somewhere that these were becoming more popular in the US also. Any opinions? Seems to me like potential for a lot of drag; perhaps stiffer; clearly more stable at on the hard!!


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## Jeff_H

I think that there are a lot of very practical reasons why Bilge Keels (twin Keels) make sense, but none of them have much to do with sailing ability. Which is not to say, that it is not possible to design a very workable bilge keel design, which will offer reasonable performance, shallower draft and so on, but twin keels generally require taking a hit on performance as compared to the same hull and rig with a deeper draft fin keel. The reality is that by necessity, bilge keels with a shallower draft will have end up with some trade off of greater displacement (since more ballast is required to achieve the same vertical center of gravity), less stability, and/or more drag (more wetted surface and frontal area). 

In theory you can try to optimize the configuration of the bilge keels to produce the best performance possible, but you can also do the same thing with a deeper fin keel, so it becomes something an arms race with the deeper fin wining in term of performance at any level of optimization. 

Similarly, a deeper fin keel of equal stability and weight to a particular bilge keel design would also tend to have a better motion comfort since its deeper draft would generate a higher roll moment of inertia and better dampening. 

But in a broad general sense, cruising boats are rarely optimized for out and out performance. Instead they are optimized for the practical requirements of their purpose, which means greater carrying capacity, simplicity, and robustness than would appropriate for a goal of simply going as fast as a boat possibly can. In that vein, bilge keels might be seen as simply another worthwhile compromise in performance for cruising practicality. 

I don't know where you read that bilge keels are becoming more popular in the U.S. but I personally don't believe that bilge keel boats are becoming more popular around here. If anything I would suggest that they are a very hard sell here on the U.S. Atlantic Coast and so would probably take a bigger depreciation hit at resale time. That said, they may be a cult boat that holds their value since so few models are available on the market. 

My own personal concern with bilge keels and the reason that I personally would not buy one for myself, is is similar to my concern with wing keels. In my experience when you accidentally run either aground, it is far harder to get free. An argument might be be made that a shallower draft boat is less likely to run aground as frequently, and that arguement may have merit for some people, but it does not work acceptably well for my own personal preferences. 

Jeff


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## mdi

A cruising requirement for me is a skeg hung rudder, whatever you do, do that, my 2 cents.


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## PCP

mdi said:


> A cruising requirement for me is a skeg hung rudder, whatever you do, do that, my 2 cents.


There are some cruising boats that in their low draft version have the ruder at almost the same draft as the keel. That looks dangerous to me and on those cases a skeg rudder seems to make semse to me.

But if a boat has the keel considerably deeper than the rudder, the chances of hitting with the rudder instead of the keel are not considerable and a more efficient spade rudder is the way to go :

*Loose pounds, get better feel, reduce maintenance, improve lift, reduce drag and re-learn
the joy of driving your boat.*

http://www.fastcomposites.ca/publications/WhitePapers/BetterSpadeRudder.pdf

Regards

Paulo


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## tdw

PCP said:


> *Already from this century:*
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Regards
> 
> Paulo


If it were financially possible I'd have that later model Malo (or Hallberg Rassey) in a flash and given the overall build quality of the beasts I have no doubt that the Malo spade would be stronger than many skeg hung rudders.

While I would never consider a deep fin/torpedo with leading edge exposed arrangement, improvements in underwater design allow us to have faster cruising boats that do not sacrifice their load carrying capacity. It may not seem much but that extra knot or two makes one hell of a difference on even a coastal passage and without doubt enhances the simple pleasure of the sailing.


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## utchuckd

Hey all, OP just checking back in saying thanks for the responses. Some very good stuff in here and I appreciate it.


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## Livia

Caveats: As people have already mentioned, the full/fin keel discussion is complicated by the fact that displacement and hull shape are often related to the designers fin choice. Also, the type of person who decides to go offshore cruising in a fin keel boat is probably a different person than the type of person who decides to go offshore cruising in a full keel boat.

We are on a fin keel, skeg hung rudder, reverse sloped transom sloop.

A few observations from cruising down the N American coast to Mexico:
- Cruisers motor a lot.
- Cruisers in fin keel boats motor less often.
- Although one hopes one's major passages are mostly downwind, we have done a fair amount of beating coastally, particularly if we are sailing on and off our anchor.
- There are a lot of offshore cruisers in fin keel boats.


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## travlin-easy

tdw said:


> If it were financially possible I'd have that later model Malo (or Hallberg Rassey) in a flash and given the overall build quality of the beasts I have no doubt that the Malo spade would be stronger than many skeg hung rudders.
> 
> While I would never consider a deep fin/torpedo with leading edge exposed arrangement, improvements in underwater design allow us to have faster cruising boats that do not sacrifice their load carrying capacity. It may not seem much but that extra knot or two makes one hell of a difference on even a coastal passage and without doubt enhances the simple pleasure of the sailing.


Fuzzy,

I'm by no means an expert at sailboat designs, but looking at the above photo the first thing that comes to mind is both the prop and rudder could easily be susceptible to damage from something as small as a piece of driftwood, especially if the engine was running hard against the current. In my mind I can readily picture a partly submerged snag washing down the hull, being drawn into the prop, and jamming into the rudder hard enough from the engine's torque to blow the rudder and rip out the boat's bottom. I don't see this as a remote possibility with a full-keel boat and skeg mounted rudder. To me, it just seems like common sense, but maybe there's something I'm missing. And, of course, things like this don't happen when the weather's calm and conditions are ideal. For some unexplained reason, all of these incidences seem to occur during nasty storms and dangerous conditions.

Here's a photo of a friend's 32.5 Morgan which clearly shows it would be difficult to take out the rudder or prop even when hard aground.









Gary


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## Brent Swain

If you take advantage of the twin keel being more upright, thus each only having to be half the size of a single keel ,they have no more wetted surface than a long fin keel, and have far less wetted surface than a full length keel.
I hope to experiment with tip shapes, to eliminate the tip vortexes of twin keels. Shouldn't be too hard to accomplish.


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## JordanH

Between Jeff_H and my fellow barn-door-rudder brethren, I don't have much to add. As a relatively new skipper, I can't tell you how much tight marina's scare me. Jeff is bang on with his technical points above... but the original poster is a self-proclaimed newbie which perhaps gives me a more recent perspective since I've recently gone through the same question and discovery.

In my quest for a boat, I sailed on as many as I could. Three examples,
1) I sailed a Shark 24 numerous times ( http://www.shark24.org/membership/images/plan3.jpg ) which was passable but I didn't like the boat. Tacking was easy enough but required a little time to get through the wind.

2) I then had the opportunity to skipper a J24. This thing quickly and accurately pivoted around a central point. It tacked so quickly that I would often over shoot my intended angles. Quick, easy and I needed very little input to get it through the wind in a second.

3) I settled on my lovely little Contessa 26... a modified full keel with a keel hung rudder. Oh boy. If I though the shark was slow through the corners, the full-keel takes a loooong time. I won't be dicing it up in a match racing duel any time with my baby.

From a newbie perspective, the type of keel & rudder combination drastically affects the handling of the vessel. In a car metaphor, a fin keel is going to be more like a twitchy sports car that will respond to lesser steering inputs (to varying degrees of course) and will require greater attention to your course. A full keel will feel more like a limo... you plan your corners ahead of time and will be more forgiving to newbie-skipper steering input. We often lapse in our ability to sail in a steady course for long periods of time. 

As a newbie, a full keel seems easier to steer for long distance without the aid of autohelm, but is harder to dock, reverse and handle in tight quarters.

Another point that wasn't mentioned above is the turning radius. From my limited experience, I've found that the narrower the fin keel, the tighter the turning radius. The Farr 30 (Mumm 30) on which I sometimes race spins on a dime as does the J24. The Shark less so but still quite tight. My longer keeled Contessa likes a wide arc. I suspect this is primarily due to keel shape but I'll leave that as a homework exercise for Jeff_H to explain. ;-)


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## killarney_sailor

I think you make a choice and with the choice comes a particular set of advantages and disadvantages. I also think that it is quite simplistic to say that full keels are this and fin keels are that. A lot depends on the quality of design of the particular boat, i.e there are some full keels that are very well-designed and some that are not. Same for fin keels, centerboarders, and bilge keelers. If I was a full keel person I could find full keel boats that were terrible to sail and fin keelers that I would love to sail.

I have a skeg-mounted rudder now but have had fins as well. On an earlier boat (S&S designed 29') I was amazed to see how little strength the skeg had when the rudder was removed. The strength of the unit was coming from the rudder shaft, not the skeg. The reason why the rudder was off, was that it had been broken when the boat came down onto the tip of the rudder (it went downward a bit from the skeg) on a sandbar at a harbor I should not have been trying to enter with waves as they were. The force tore the rudder blade away from the shaft which jammed the rudder againt the fairing that came down from the hull. If it has been a spade rudder, I suspect that the damage might have been similar although perhaps less tearing and more bending of the shaft.

Final point - the keel does not exist in isolation from the rest of the design. You can't buy an XYZ 34 with a long keel and the same boat with a modern fin - so what we are getting when we make a choice is the whole package of design choices and compromises.


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## CapnBilll

On the bluewater boards, they make it sound like if you aren't in a traditional full keeled boat 40' or better, you are suicidal to sail in anything larger than a 1 acre pond. 

The number of fin keeled boats in transoceanic races somewhat belies that. The large number of small fin keelers in the Carribean also kinda belies that.

So I would say any respectable built sail boat thats not too big for your crew to handle, and that YOU can dock comfortably, will take you anywhere you are likely to go as long as you respect it's, and your limitations.

After all how many of us have rounded the capes in winter, or done a Northwest passage, or rounded Antartica?

I prefer sailing in tropical lattitudes outside of hurricane season. That makes it unlikely that I will see anything over a F8 in open water. Even more likely I will be running for the lee of the nearest landmass as soon as a storm is forming in the area, long before the waves build to dangerous levels. 

Would a "bulletproof" ship be nice, well yes; but I probably wouldn't sail it as much as I would a light cheap production boat that is easy to dock.


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## killarney_sailor

*Capt Bill, some responses*



CapnBilll said:


> On the bluewater boards, they make it sound like if you aren't in a traditional full keeled boat 40' or better, you are suicidal to sail in anything larger than a 1 acre pond.
> 
> The number of fin keeled boats in transoceanic races somewhat belies that. The large number of small fin keelers in the Carribean also kinda belies that.
> 
> So I would say any respectable built sail boat thats not too big for your crew to handle, and that YOU can dock comfortably, will take you anywhere you are likely to go as long as you respect it's, and your limitations.
> 
> After all how many of us have rounded the capes in winter, or done a Northwest passage, or rounded Antartica?
> 
> I prefer sailing in tropical lattitudes outside of hurricane season. That makes it unlikely that I will see anything over a F8 in open water. Even more likely I will be running for the lee of the nearest landmass as soon as a storm is forming in the area, long before the waves build to dangerous levels.
> 
> Would a "bulletproof" ship be nice, well yes; but I probably wouldn't sail it as much as I would a light cheap production boat that is easy to dock.


Some responses - based on our experiences
1. I think the bluewater board folks need to get out more. From what we see there are more fin-keeled (think Bob Perry, fairly conservative fins) boats that full-keeled boats (lets say attached rudder types).

2. Don't try to take too many conclusions based on trans-oceanic race boats. Their crews are different and so are their priorities 1) make it and 2) win - comfort or ease of handling are way down the list, if on it at all.

3. For extended cruising ease of docking is not much of a priority since you so rarely do it. We docked in Panama, Tahiti, and Australia on a trip from Florida to Australia.

4. You can get more than F8 in the tropics during the recommended time of the year. We got F10 SE of Tahiti.

5. We are circumnavigating Antarctica (and the North Pole too), but will never be closer than around 1800 nm (in South Africa), and it will be in summer, but I still have considerable trepidation about that part of the trip.


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## Brent Swain

My first boat had a long keel with rudder attached. She tacked on a dime , whether you wanted her to , or not.
My second boat, with a much longer keel, was not much better, and tacked much quicker than my current boat, with short twin keels. The difference was hull balance; hull shape.
Keel length had little effect on directional stability. 
Some race boats, slow to tack, have been said to have 'Excess directional stability." That is due to hull shape, not keel length.
There is no such thing as "Excess directional stability" on an offshore cruising boat; the more the better.
You see fewer and fewer boats cruising offshore with full length keels. Even out there, they are increasingly rare.


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## JordanH

newbee said:


> We have sold our home and are looking for a liveaboard to learn on in Maine. Here is what we know about ourselves. We love being on the water, and are hardy souls who can share a small space for extended periods of time and keep our sense of humor. We bought a tiny little Hunter 21 last summer as our first "learning boat" and had a blast! We are starting the process of finding a boat in the 29-38 foot range with lots of headroom, a forgiving hull, and a reasonable learning curve. We have a budget of around 60,000$ All advice is welcome! Please chime in!!!!
> So far we have considered A Sabre 38 with a fin keel, and any Island Packet between 29 and 32 feet. The bigger IP's are out of our financial reach. The Sabre is a BEAUTIFUL boat, but with our limited experience more than we can handle?
> Thanks,
> newbee


Hi newbee,
You should post this question as a new thread, rather than in a this unrelated thread. You'll likely get more exposure and more advice that way. Perhaps the mods can help separate the last few posts into a new thread for you?
Cheers,
J.


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## RealityCheck

The Hobby Horse action while even at a mooring is one disadvantage on some full keel boats. I was a Bay Host a reasonably protected bay (Leinster Bay, St John USVI), a year or so back, when a Ferry Boat passing a quarter mile away caused one boat to hobby so bad it cause some injury to two occupants who were not expecting it. The major problem is the boat continued to hobby horse well after all other boats were totally stable again... actually for probably 2 full minutes. 

I responded to a cry for help and was some 70 yards away and by the time I deployed my dink and arrived some 3 min later I was just able to board the boat which was still having Hobby Horse movements. The two had minor bruises and one a cut to the head from hitting something when thrown down in the cabin. Nether wanted / would allow medical assistance to be called but did show bruises for several days.

Most other boats in the harbour were fin keel boats and Cats but at least one other appeared to be a 3/4 keel but was further up in the bay and did not suffer any significant disturbance.

I've seen many full keel boats similarly effected by swells of a short duration that seem to trip the hobby horse effect. often causing the bow sprints to go under water and most of the Rudders to be exposed while adjacent fin keel and cats had only a minor effect. It would have been Very difficult/ dangerous to effect any forward deck work during these events.

All boats have good and some not so good responses to specific weather/ sea conditions, you can only go with what you feel is best for your type and location of cruising and be prepared for what comes.


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## BryceGTX

utchuckd said:


> Can somebody pro/con a full vs. fin keel for a newbie (will learn to sail on said boat) and taking it thru the Caribbean? All I can seem to come up with so far is fin keel is better to the wind, and a full keel will protect your rudder.


Probably the single most important reason why full keel boats are considered blue water has been discussed for over a hundred years, but interestingly enough not yet pointed out on this thread thus far.

Below is a picture taken from the book "Yacht Architecture" written in 1897. Notice that they were quite familiar with fin keels and bulb ballast as they describe in this book. Contrary to popular belief, a very old design.

What they knew back one hundred years ago was that hull form can create a significant amount of righting moment. And these two hulls create radically different hull righting moments. The flat bottom bulb keel creates considerably more hull righting moment than the full keel design because it has a flatter bottom.

So the full keel design is given more ballast. The ratio of ballast righting moment to hull righting moment is much higher in the full keel boat. This causes the full keel boat to be considerably more friendly in rough water. The reason is that the full keel tends to remain upright on waves, yet the flat bottom boat tends to heel with the wave angle.

And as we all know a full keel boat is more comfortable in rough seas. That is well documented in hundreds of years of Yacht design. So if you really want to put a number on "Blue Water", you should look at the ratio of mass righting moment to hull righting moment. The full keel by its very design forces a high ratio.
Bryce


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## BryceGTX

Jeff_H said:


> Wing keels
> Wing keels are a specialized type of bulb keel. Instead of a torpedo shaped bulb there are small lead wings more or less perpendicular to the keel. These concentrate weight lower like a bulb and properly designed they also can useful in reducing tip vortex. There has been some discussion that wings increase the effective span of the keel when heeled over but this does not seem to be born out in tank testing of the short wings currently being used in production sailboats. Not all wings are created equal. They potentially offer a lot of advantages, but they are heavily dependent on the quality of the design and I really think that many wing designs are not really working to their potential.
> Jeff


Interestingly enough, if we consider the bulb keel to be the oldest design, the wing keel is one of the newer designs. And I tend to agree it has yet to reveal its full potential.

On the other hand, I think Catalina has done a very good job of succeeding in the effective design of the wing keel. The wing is quite big almost as much area as the keel itself. This would appear to actually increase the vertical projection of surface area to lateral movement. Not to mention the change in form with heel angle. The only keel design I know of that has this feature.

Interestingly enough, it is often the racing rules that either directly prohibit or otherwise descriminate (girth measurements) against an effectively designed wing keel. And since racing rules often dictate or influence sailboat design, we find ourselves with sometimes marginal designs for our boats.

This fact has been pointed out for well over 150 years as sailboat designs were even then often compromised by racing regulations. Sadly enough, the bulb design is actually the optimal design to comply with a girth restriction as opposed to an optimal design for a keel.
Bryce


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## sea_hunter

LOL, this argument is always fun. Generally both work as advertised, but full keels rarely fall off.


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## newbee

Bryce, you said :
Sadly enough, the bulb design is actually the optimal design to comply with a girth restriction as opposed to an optimal design for a keel.

We have been given the opportunity to modify the full keel of a 38 ft Sabre we are in love with to a bulb keel by Mars metal. What would the consequences be? We would be choosing this option because we are very inexperienced sailors looking to learn on our liveaboard. The modification would take 1 1/2 feet off of a 6'6" keel and allow us coastal cruising and maybe a trip south.

Thanks,
newbee


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## sea_hunter

Newbee, While there were a number of keel options on the 38, I think a little more research is required. If there's no "real" available information, or even if there is; I think a professional opinion from a naval architect would be in order.


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## PCP

killarney_sailor said:


> Some responses - based on our experiences
> 1. I think the bluewater board folks need to get out more. From what we see there are more fin-keeled (think Bob Perry, fairly conservative fins) boats that full-keeled boats (lets say attached rudder types).
> 
> ...


More important to see what is still out there is to see what are the boat designers (that know more than you or me about boats) are designing now for bluewater cruising boats: Malo, Halberg Rassy, Najad, Moody, Oyster, Tartan, Morris, Amel&#8230;.all bluewater boats, all boats that in a distant past used to be full keelers are now fin keelers.

Regarding designs made now (and not old designs that are still made) there are not a single major designer that is proposing a full keeler or any production shipyard that is making one.

Well, not so many years ago a British shipyard had tried that and went bankrupt rapidly.

Regards

Paulo


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## sea_hunter

PCP said:


> More important to see what is still out there is to see what are the boat designers (that know more than you or me about boats) are designing now for bluewater cruising boats: Malo, Halberg Rassy, Najad, Moody, Oyster, Tartan, Morris, Amel&#8230;.all bluewater boats, all boats that in a distant past used to be full keelers are now fin keelers.


Fin Keels have nothing to do with seaworthiness; they're about speed/production costs = profits. Do a "loses keel" on Google. Check out the images too.


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## PCP

sea_hunter said:


> Fin Keels have nothing to do with seaworthiness; they're about speed/production costs = profits. Do a "loses keel" on Google. Check out the images too.


You seem to have a trauma with losing the keel. Do you know how many Benetaus were produced? Well, they make between 1000 and 2000 a year, make a guess!

Do you know how many keels where lost? I never heard about a single one

If you make radical very low weight racers the chances are that if something goes wrong on the construction or the architect calculations are too optimistic, they may have problems with the keel. But anyway on those boats keels should be checked regularly and they are not designed for bluewater cruising.

I have given you an example with Benetau and that is not a boat designed specifically with bluewater cruising on mind. Now regarding those bluewater boats that I was talking about : Malo, Halberg Rassy, Najad, Moody, Oyster, Tartan, Morris, Amel, do you ever heard about any problem with a keel?

So why a fin keel if properly designed and produced is lesser safer or make a boat less seaworthy? Fin keels are more efficient and they do the job better than full keels and that's why NA are not using full keels anymore.

Regards

Paulo


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## mitiempo

I agree with Paulo.

Of all the sailboats sailing today I would guess about 80 to 90% are fin keel boats. The full keel boats like the Albergs, Cape Dory, etc are a very small percentage and very few full keel boats are produced today.

Very few have ever lost their keel.

They have everything to do with seaworthiness. A boat that sails efficiently and is easy to maneuver is always a better choice.


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## Faster

That would be an interesting list..

What manufacturers currently producing boats still build 'full keel' boats?

Island Packet and ?????


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## mitiempo

Cape George is one I can think of, for those wanting a modern (fiberglass) version of a 50 year old Atkins design. There are a few others, but not many.

Early fiberglass boats were essentially copies of the wooden boats that preceded them. A plank on frame boat is not as structurally able to carry a fin keel and most had full keels with the ballast attached to the deadwood. 
Modern construction allowed design to change and allowed fin keels to be produced that were stronger than the full keel wooden boats of the past.

The Valiant 40 is a good example of a fin keel boat that has proven itself over the last 39 years.


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## mitiempo

The first large (42') fiberglass cruising sailboat was called Arion. Designed in 1950 by Sidney Herreschoff she had both a fin keel and a spade rudder. She is still sailing. damian mclaughlin corporation - Arethusa

It is not that new an idea and well proven.


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## ccriders

utchuckd,
So there; see what I meant when I said "if you can decide in your own head" full vs fin keels?
There really is now way to simplify this decision but to think hard about the kind of sailing you are going to do and where you are likely to do it and then mentally start building the boat of your dreams. Then comes the hard part of finding that boat without having to commission a naval architect. 
And then you come to uderstand that saying "every boat is a compromise."
I think very very few people ever got their last boat with their first boat. So don't kill yourself trying to find that perfect boat right out of the box. 
Have fun with this journey.
John


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## killarney_sailor

Arion is a very pretty boat. I imagine a modern version of that would sell a few copies.


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## souljour2000

that's a nice sailboat...thanks for posting MiTiemp...My own boat has an 8 foot beam too...but she's only 29-feet long ! This is interesting...Perhaps alot more 40-foot+ boats would be speedsters like this one if folks didn't have that understandably strong desire for roominess....that canoe stern helps her get out of her own way too though....


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## Brent Swain

sea_hunter said:


> Fin Keels have nothing to do with seaworthiness; they're about speed/production costs = profits. Do a "loses keel" on Google. Check out the images too.


The single keel on my 36 footer has over 4.6 million pounds of tensile strength in the steel supporting them. Not much chance of that breaking. Keel loses are on high aspect ratio , minimum design racing boats , not on longish fin keels, common on cruising boats.


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## BryceGTX

newbee said:


> We have been given the opportunity to modify the full keel of a 38 ft Sabre we are in love with to a bulb keel by Mars metal. What would the consequences be? We would be choosing this option because we are very inexperienced sailors looking to learn on our liveaboard. The modification would take 1 1/2 feet off of a 6'6" keel and allow us coastal cruising and maybe a trip south.
> 
> Thanks,
> newbee


If I were you, I would talk to Sabre. The new Sabres show a wing keel for a shoal. Probably a smaller wing though. Not sure about the year of your boat, but the Sabres appear to be a great example of a typical American cruising design. A lot of keel weight, good solid hull.

No doubt anyone can design a bulb keel to create the same righting moment as your existing keel. Unfortuneately, such a keel only adds drag with no hydrodynamic benefit. You will clearly lose some pointing with the bulb. If you want to do something useful with the bulb mass, reshape it to a wing.

My feelings are that a good wing design needs considerable area to gain some hydrodynamic benefit. The benefit to gain is the same or increasing resistance to leway movement with heeling. And possibly some benefit to resistance to vertical moment.

The problems I see with adding a wing to the bottom of an existing shortened keel deals with vertical forces. Movement of the hull vertically creates large forces on the keel-wing joint.

The wing keel is unique in that it can create large resistance to vertical moment. Like a huge rocker stopper.  It resists downward movement (same as the hull). And more interestingly enough, it resists upward movement unlike any other keel design.

Again, I would contact Sabre.
Bryce


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## BryceGTX

mitiempo said:


> The first large (42') fiberglass cruising sailboat was called Arion. Designed in 1950 by Sidney Herreschoff she had both a fin keel and a spade rudder. She is still sailing.
> 
> It is not that new an idea and well proven.


Boy, it is pretty tough to compare this to newer fin keel boats. This boat only has an 8 foot beam and its 40 feet long. And 50% of its mass is in its keel. And its hull is more V shaped than flat. The keel is longitudinally long rather than vertically long like a newer fin keel.

Because its so narrow and v-shaped, this will have a lot in common with the full keel boats. The full keel boats owe much of there sea handling capabilities to the hull design, not necessarily to the keel design.

I think the Valiant is probably very similar. Its hull design is more v-shaped than flat. This contributes immensely to its sea handling.

But you are quite right, the fin design and even the flat hulls have been around for centries.
Bryce


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## mitiempo

Fin keel or full keel, a boat doesn't have to be fat.

The Valiant of course isn't quite as narrow as Arion. But after almost 40 years it helps prove a full keel isn't necessary for a boat to be "offshore" capable. There are also many others that have traveled far and wide with fin keels.

I can't think of many full keel boats with high efficiency keels - just large ones with a great deal more wetted surface than necessary.


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## MarioG

With in the matter of a year I went from swing keel (Chrysler 22) to fin keel (Chrysler 26) to modifed full keel (Endeavor 32) is my only claim to knowadge.

The swing keel was great for the lake sailing we did and it being our 1st sailboat made learning what running aground meant with the ease of dealing with it. I could see sailing it on the coast in fairer weather. Also great for getting in and out of the water. we stored it on the hard between outtings with mast up.

The fin keel was on our coastal/sound boat that we sailed long weekends on unfamiliar waters. Great for the rougher larger waters but it didn't stop me from thinking how nice if it was also the swing keel version when we ran aground a few times. Fun all around thou I'm never sure the other boats knew we were racing at times.

Now that we are liveaboard cruisiers the modified full keel meets our needs very well.
With the experiance we gained with the other 2 boats, We have been able to cruise the east coast sailing alot on the outside or even sailing the ICW due to its shallow draft. I guess we have learned how to handle it well enough that I have been able to back it out of tight spaces with out much trouble. I know I don't sail as fast as the fin keel boats but I'm in no hurry and it is my home. I don't think I would like it as much if I was only useing it on weekends and I was out to play.

So me being NO expert can only say that it really depends on what type of sailing you do as to what type of keel is better.


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## barefootnavigator

This is just my 2 cents and all its worth. I must have missed it but did anyone mention the safety factor of being able to heave to? If you have ever been in a third world boat yard you will appreciate the ease and safety of hauling out a full keel vs a fin keel. A full keel boat can be safely careened for a quickie bottom job, try that with a fin keel. If you haven't seen what happens when a fin keel hits a reef at 6 knots you should come to the Pacific North West and visit any boatyard, its pretty scary. Just a few thoughts


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## Faster

barefootnavigator said:


> ...... If you haven't seen what happens when a fin keel hits a reef at 6 knots you should come to the Pacific North West and visit any boatyard, its pretty scary. Just a few thoughts


True enough, but I'd think the premise would be to avoid such encounters.. I know accidents happen but I'd hate to think that ramming a rock would be a frequent enough occurrence to dissuade me from a particular boat type...


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## barefootnavigator

Like I said just my 2 cents. Here in the Salish Sea we have 13' tidal fall, 6 plus knot currents, frequent heavy weather, un-charted rocks, fog, blah, blah, blah, I was surprised how many experienced people hit things around here. 
PS you know the old saying, if you haven't been aground, you haven't been around.


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## blt2ski

Barefoot,

Both faster and myself are in the salish sea, we know about the 13-14' tide changes......both of us prefer fin keels! Hell, I've even run my fin keel aground once or twice or.......ok, maybe I'd better shut up on that one.....

The point being, in our lighter winds, a lighter fin style boat will keep you sailing longer than a heavy fin keel that is less SA/disp than a higher AS/disp fin. 

I was looking at a march or maybe feb sail magizine the other day, there is an article with the authors dream boat. One thing he mentioned, easy to move so it would sail under light winds. Also made some comments about some areas of the world, Puget Ound was one, taller mast and more SA for the light wind days.

Now does a fin equal an easily driven hull? not sure, but it is easier to move than a full keel.

marty


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## blt2ski

onebetter look at this thread if one feel one can not runa fin keel aground per say and do bottom work. This happens in the UK etc ALL the time! picture if it works, which is in the thread is in northern Wales, boat IIRC is 42', and has a 7' draft.

Marty


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## barefootnavigator

Very good point and this is where design, skill, and sail quality and inventory come into play. I sail a very small, heavy 22' full keeler that can kill a standard 30' fin on any point of sail in light winds. I also sail engine-less which might be why I purchased a high performance boat. I purchased the boat for blue water so performance and safety were at the top of my list. At the end of the day its all about personal preference. My sailing skills are average at best so I chose a boat that I knew would take care of me. I guess another factor in choice might be price, you can drop 10 grand on an old full keel plastic fantastic and set off to see the world. Fin keel boats have there place as do full keel boats, I've owned both.


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## jackdale

barefootnavigator said:


> A full keel boat can be safely careened for a quickie bottom job, try that with a fin keel.


The Copelands careened Baghera to repair a rudder bearing. There is a photo in one of the boats.


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## blt2ski

Even your 3'6" of draft, 2' less than mine would not have gotten you into Fishermans bay on lopez at about 11:30 am on july 1 last summer. Tide was a -2.5, channel is dredged to 5' at 0 tide! While you would not have waited as long to get into it after low tide as I did, you would still be waiting! altho not as long as another fellow with his Cat 420mkII with a bit over 7' of draft! Both his and another were sitting on the ground at the dock when low tide hit in the marina! neither suffered any damage. I bumped going in......

Generally speaking, at least off of Edmonds where I am, my depth guage does not work, as it is usually deeper than 400', so reality is, there are VERY few spots here in the sailish sea one needs to WORRY about draft as compared to the east coast.

Then your boat is smaller in WL, weighs 1500 more lbs than mine, 100# less SA........maybe you can out point me, then again...........I doubt you will sail faster ALL the time. One can get a fin to lie ahule, yeah a bit harder, but one can do it! 

At the end of the day, there is not a right or wrong. Only what one thinks will suit them best.


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## Jeff_H

barefootnavigator said:


> This is just my 2 cents and all its worth. I must have missed it but did anyone mention the safety factor of being able to heave to? If you have ever been in a third world boat yard you will appreciate the ease and safety of hauling out a full keel vs a fin keel. A full keel boat can be safely careened for a quickie bottom job, try that with a fin keel. If you haven't seen what happens when a fin keel hits a reef at 6 knots you should come to the Pacific North West and visit any boatyard, its pretty scary. Just a few thoughts


Not in any detail but being able to hove to really can add to the safety of the boat. Boats heave to as a system which balances rig and keel. Not all full keel boats heave to equally and some will not heave to very well. And while most fin keel boat will heave to, they tend to make more leeway and some need to have sail reduced and some fin keel boats won't heave to at all.

For that reason, I generally suggest that potential boat buyers include heaving to as a part of a seatrial if they are not familiar with a design, and that boat owners practice heaving to in various conditions to learn.

Good point about groundings. As mentioned fin keels need to be carefully engineered to survive an impact. There is a lot of leverage. The good news is that with a bolt keel, the boat can generally be rebuilt good as news rather than totalled if it is kept afloat without flooding.

By the same token, encasulated keels are especially vulnerable to damage in a hard grounding, and many, if not most full keel fiberglass boats have encapsulated keels. Once breached, an encapsulated keel is almost impossible to get back to a 'like new'.

Jeff


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## tdw

Having all too recently run over a mooring line and ended up with the whole thing wrapped up in prop shaft and a nearly submerged tender I can well see one of the arguments for a full keel but overall I'm afraid I'll still stick with fin and try and be a tadge more careful.


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## PCP

barefootnavigator said:


> .. I sail a very small, heavy 22' full keeler that can kill a standard 30' fin on any point of sail in light winds. ...


What do you mean by that "kill" thing? You mean if you manage to ram the light boat you can sink it?

Regards

Paulo


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## blt2ski

Paulo,

I'm reading as he can sail higher upwind and faster at any point of sail than a lighter fin keel! Not sure I would believe it myself............

marty


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## blt2ski

Fuzzy,

I have some pics of wrapping a crab pot line tween the top of the rudder and the hull. Not fun. Fortunetly it was AFTER we won the race that night to claim 1st place in that race series. Still trying to figure out why a crab pot was out, being as the season did not open for a week.......... I did ge the 2011 bent prop from YC out of that one.......that is when the spouse found out about this misadventure.......double OUCH!.......


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## pvajko

PCP said:


> So why a fin keel if properly designed and produced is lesser safer or make a boat less seaworthy?


Just wonder if anybody here read Marchaj's book 'Seaworthiness: The Forgotten Factor' where he shows why: the most important reason is that a full keel with its bigger surface area damps the rolling motion better.

It is a very interesting book, it discusses the dynamics of sailing in great detail and points out that while a fin keel performs much better in ideal conditions (flat water), stormy weather with big seas is a whole different story.


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## PCP

pvajko said:


> Just wonder if anybody here read Marchaj's book 'Seaworthiness: The Forgotten Factor' where he shows why: the most important reason is that a full keel with its bigger surface area damps the rolling motion better.
> 
> It is a very interesting book, it discusses the dynamics of sailing in great detail and points out that while a fin keel performs much better in ideal conditions (flat water), stormy weather with big seas is a whole different story.


Good book, but old book. Are you familiar with the term "tripping on the keel"?



















Regards

Paulo


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## pvajko

PCP said:


> Good book, but old book.


Can you recommend a newer one, at least as good as his, backed with solid physics and math?


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## skygazer

PCP said:


> Good book, but old book. Are you familiar with the term "tripping on the keel"?
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Regards
> 
> Paulo


Paulo, I'm interested in this subject, only having had experience with full keels. Here is what I see, please go into a bit more detail if you see something else.

The drawing of the "tripping" on the keel looks like they are located where waves hit shallow water and break. An area we all try mightily to avoid. Seems that with a small keel or no keel the boat would be "flipping" instead of tripping. Not sure being tossed from the boat is better than filling the cockpit. Plus, trying to get some rest if the boat is rolling with the steepness of the wave fronts, that seems like it would be difficult.


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## skygazer

pvajko said:


> Just wonder if anybody here read Marchaj's book 'Seaworthiness: The Forgotten Factor' where he shows why: the most important reason is that a full keel with its bigger surface area damps the rolling motion better.
> 
> It is a very interesting book, it discusses the dynamics of sailing in great detail and points out that while a fin keel performs much better in ideal conditions (flat water), stormy weather with big seas is a whole different story.


Thank you for mentioning this book. I searched, got a look at some inside pages, and ordered one a minute ago.

One page I saw talked about the motion within a wave, and how a short keel is affected only by the motion where it is located, but a longer keel averages the motion out more, throwing the boat around less. This particularly applied to a course other than broadside to the waves. Also, I think it said that the turbulence coming off the short fin keel reduced the effectiveness of the rudder, the idea seemed to be that in flat water the fin keel worked better, but in rough conditions the long keel worked better.

Overall, the book looked a bit "dry" for pleasure reading, but I could digest at least a bit of what I read, so I think I'll learn some things from it.


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## Jeff_H

Marchaj's book was a seminal work when it was written. Like Tony Marchaj's other books it did a great job of gathering existing testing, studies and performing targeted testing and explaining the principles in ways that a moderately technically savy amatuer could understand. For us normal sailors Tony's book really progressed the understanding of the factors involved in producing a seaworthy boat. 

But the book was written 30 years ago. The research data was based on the testing available at the time. Most of the basic principles remain 100% valid, but many of the conclusions relate to the specific hull forms, keels, rigs and so on that existed at the time, and did not have the advantage of the ongoing testing which has occured in the 30years since. 

In the countervening 30 years, designers, using much more sophisticated testing and design tools, have considered the basic principles that were identified in 'Seaworthiness' and designed boats which purposefully address these issues. 

I would respectfully suggest that that Pvajko is mistaken when he says:
"The most important reason is that a full keel with its bigger surface area damps the rolling motion better." 
"While a fin keel performs much better in ideal conditions (flat water), stormy weather with big seas is a whole different story. "

I would suggest that, in the first quote, Pvajko is in part misinterpreting what was being said, but in both cases, these conclusions were based on the type-forms and limited testing available at the time that the book was written. 

Today, seaworthiness is no longer forgotten. Designers have long since learned how to design around the concerns raised in 'Seaworthiness' and have the tools to make both of the quoted statements inaccurate. 


Jeff


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## skygazer

Thank you Jeff. I wish I could say that I understand this stuff, but I have only a vague grasp and can be readily influenced by logical sounding information. 

Perhaps I don't need to worry too much, as I can't really afford a boat less than 30 years old! 

I've spent most of my time on wooden sailboats with full keels, so I have no comparison. I am however quite interested in the fin keel concept.

In the non-consecutive pages of the book that I was allowed to look at, I had the impression that it was not the surface area of the keel that was so helpful. It was the linear length (bow to stern), which when running downwind put the different parts of the keel in different (and differing) parts of the wave motion, thus no one part has such a great effect. Plus the old style V hull went deeper, divers know that just a slight increase in depth greatly lowers the wave motion effect.

Of course, I can't help thinking that very deep fin keels would also reach down into less violent motion.

Have you any suggestions on a good place to look for newer information? And are computer models a big part of the new design? I'm a bit suspicious of computer modeling at the moment. We just had a long winter of totally failed computer modeling of atmospheric motion, which gave very poor weather predictions, the worst I've ever seen actually.


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## PCP

pvajko said:


> Can you recommend a newer one, at least as good as his, backed with solid physics and math?





skygazer said:


> Paulo, I'm interested in this subject, only having had experience with full keels. Here is what I see, please go into a bit more detail if you see something else.
> 
> The drawing of the "tripping" on the keel looks like they are located where waves hit shallow water and break. An area we all try mightily to avoid. Seems that with a small keel or no keel the boat would be "flipping" instead of tripping. Not sure being tossed from the boat is better than filling the cockpit. Plus, trying to get some rest if the boat is rolling with the steepness of the wave fronts, that seems like it would be difficult.


Hi!,

No I cannot recommend another one. Taking into consideration what Jeff has said, there are 30 years of sailboat design between that book and today and 30 years where mathematical computing models of boats and hydrodynamics and tank testing have assumed a main role to understand dynamic stability and the way a boat reacts with the sea.

But more than what those studies have shown I would say that more was learned with the pragmatical work of many Naval Architects and many thousands of designs and the assessment that was made of those designs mostly by racers, that in some cases were also the designers.

Skygazer, regarding waves, breaking waves are the only real danger for a monohull and you don't find them only near shore. With a formed sea with big waves and over 35K winds the top of the waves break and if the wave is big, the top of the wave are many tons of water. On that drawing is that what is happening: it is not all the wave that is breaking (like in a beach) but just the top.

By any mean I want to say that full keels are dangerous, just showing that they have also some disadvantages in what regards seaworthiness and dynamic stability.

Those are pages of a book written by one of the biggest sailors of all time, Eric Tabarly. He was not a theorist but you can be sure he knows what he was talking about. He raced what was then modern boats (transats, circumnavigations) and him and the guys that were behind the designs he sailed had an important role in the development of today's modern hull shapes, rudders and keels. And I am saying that he knows about what he is talking about because he did not only sailed extensively racing boats but also its family boat (that he loved) the Pen Duick, an old and beautiful old full keeler.










Regards

Paulo


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## mitiempo

Steve Dashew's "Offshore Cruising Encyclopedia" has a good explanation of keel, rudder, and hull design and its effect in real offshore conditions as well as showing the advantages of computer programs for comparing design changes.


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## Waltthesalt

While we often don't do it here, a longer keel is more accommodating in supporting the boat upright when drying out your boat in a tide to work on it.


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## pvajko

Jeff_H said:


> I would suggest that, in the first quote, Pvajko is in part misinterpreting what was being said, but in both cases, these conclusions were based on the type-forms and limited testing available at the time that the book was written.


Jeff, don't misunderstand me, I'd love to be mistaken on this. I have a fin keel boat which is perfectly safe I guess for where I sail it.

I always had the impression though that for off shore sailing a full keel is safer, based partly on anecdotal evidence and Marchaj's book (which, I'm happy to admit, I may be misinterpreting, or at least oversimplifying it's reasoning).

If this is not true, that's great news for me because it means there is a lot more (and cheaper) boats to choose from in case I wanted to go off shore.

I wish there was a book or study like Marchaj's available for the general public, summarizing the past 30 years progress on this subject, because, you see, the reasoning like PCP's "[Tabarly] was not a theorist but you can be sure he knows what he was talking about", with all due respect, is not very appealing to me.



Jeff_H said:


> Today, seaworthiness is no longer forgotten. Designers have long since learned how to design around the concerns raised in 'Seaworthiness' and have the tools to make both of the quoted statements inaccurate.


I'd really be interested to learn what these tools are. Could you give more information on that, or at least point out where to look?

And please, don't get me wrong, I'm not arguing against the fin keel or any other keel or feature, I'm perfectly aware of the fact that my knowledge on this subject is way to limited to be able to argue for or against anything.


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## skygazer

PCP said:


> ......family boat (that he loved) the Pen Duick, an old and beautiful old full keeler.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Regards
> 
> Paulo


Paulo, thank you for the further details on the wave motion etc. I especially like the photo of the Pen Duick, wow! Those old style low lean boats thrill my blood. I have to say new boats look like they sit on top of the water in the wind, while the old style seem to knife through the water.

Nevertheless, I like the way I can stand up in a modern 27 ft. boat, instead of having to increase size to a 40ft plus boat. So I'm casually looking at more modern boats with headroom in the smallest size that will sail well. They all have fin keels.

I hope I can find some of the information that has been gained in the last 30 years, at a layman's level that I might understand. I've read some good points on this thread, like the fact that with wood, they could not build a strong fin keel like we can with modern materials. Also, today's better understanding of airplane type wings (keels) and their ability to generate lift.


----------



## PCP

pvajko said:


> ,,,the reasoning like PCP's "[Tabarly] was not a theorist but you can be sure he knows what he was talking about", with all due respect, is not very appealing to me.
> 
> ...


Well, as Leonard da Vinci once said: *"Experience is the mother of all Knowledge"* and Marchaj had some but not much in what regards sailing.

On other hand, experience, with full keelers and fin keelers was a thing that Eric Tabarly had in huge amounts: *"A former officer in the French navy who is often considered the father of French yachting"*.






Marchaj made a notable theorist work trying to explain reality (based on 35 year old sailing boats) trough equations and mathematical calculations but let me tell you that even if static stability is a simple and forward thing, dynamic stability is a very complicated subject (the interaction of a variable sea motion with a boat and its effects on boat stability) and even today with all tank testing and mathematical computer aided models it is far from being a settled matter.

But if the science is still messing around with dynamic stability Naval Architects have been working on the model of the best boat to fast and safely cross oceans. Probably nothing as contributed as much to the knowledge of dynamic stability than the 35 years of designing small boats to solo crossing oceans, what is called the Mini class racing:

Classe Mini

What was learned with these boats influenced bigger sailing boats, racing and cruising, in an extent that can be considered probably as the biggest influence on modern yacht design, and what was learned had all to do with dynamic stability.

Regards

Paulo


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## PCP

skygazer said:


> .....
> 
> Nevertheless, I like the way I can stand up in a modern 27 ft. boat, instead of having to increase size to a 40ft plus boat. So I'm casually looking at more modern boats with headroom in the smallest size that will sail well. They all have fin keels.
> 
> I hope I can find some of the information that has been gained in the last 30 years, at a layman's level that I might understand. I've read some good points on this thread, like the fact that with wood, they could not build a strong fin keel like we can with modern materials. Also, today's better understanding of airplane type wings (keels) and their ability to generate lift.


Regarding standing up on a 27ft boat, probably not the best way to increase seaworthiness, but related with what I said in the last post I will post in the interesting sailboat thread a boat that taking into account what was learned in 35 years of Transats on minis (including a non stop circumnavigation), is proposed as the prototype of the (very) small offshore fast boat.

Regards

Paulo


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## BryceGTX

mitiempo said:


> Fin keel or full keel, a boat doesn't have to be fat


There are two reasons to be fat. First is to get more interior room. Second is to create more righting moment. It is the easiest way to get righting moment. And of course more stiffness.

However fat hulls make for poor handling in rough water without significant keel mass. And therein lies their downfall as a substitute for a full keel boat.
Bryce


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## BryceGTX

Jeff_H said:


> I would respectfully suggest that that Pvajko is mistaken when he says:
> "The most important reason is that a full keel with its bigger surface area damps the rolling motion better."
> "While a fin keel performs much better in ideal conditions (flat water), stormy weather with big seas is a whole different story.


There really is nothing wrong with what he says, but it is incomplete. It has been well documented in 100 year old yacht design books that full keels have the advantage in big water because the rotation of the water in the wave causes the full keel boat to heel toward the wave rather than heel with the wave as with other keel designs.
Bryce


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## BryceGTX

PCP said:


> Marchaj made a notable theorist work trying to explain reality (based on 35 year old sailing boats) trough equations and mathematical calculations but let me tell you that even if static stability is a simple and forward thing, dynamic stability is a very complicated subject (the interaction of a variable sea motion with a boat and its effects on boat stability) and even today with all tank testing and mathematical computer aided models it is far from being a settled matter.


Dynamic stability to illustrate the difference between hull and keel designs is fairly trivial and can easily be simulated on any PC. Keep in mind that yacht designers from 100 years ago understood the concepts quite well. And all their calculations were with pencil and paper.



> But if the science is still messing around with dynamic stability Naval Architects have been working on the model of the best boat to fast and safely cross oceans. Probably nothing as contributed as much to the knowledge of dynamic stability than the 35 years of designing small boats to solo crossing oceans, what is called the Mini class racing:


Lol... The million dollar question is "best boat". This is kind of a silly statement. What is best boat? If you talk to one person, it it speed at the the expense of everything. As with a racer. Such a boat is great for a boat full of excited sailors whose only goal is to get from point a to b in the shortest time.

However, the average cruising couple does not is not so motivated to put up with being thrown around like a rag doll in a washing machine. So the typical cruiser needs a more rough water friendly boat. The typical IP couple will heave to and go down and sip coffee and read books while the storm rages outside.

That is the difference between a true rough water boat and the typical lightweight cruiser.
Bryce


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## PCP

BryceGTX said:


> .....
> 
> Lol... The million dollar question is "best boat". This is kind of a silly statement. What is best boat? If you talk to one person, it it speed at the the expense of everything. As with a racer. Such a boat is great for a boat full of excited sailors whose only goal is to get from point a to b in the shortest time.
> 
> ....


I did not say that there is a "best boat" or a type of boat that suits all to cross oceans following the trade winds. That is obviously a sailor's choice and some few still prefer old heavy slow full keel boats.

What I have implied is that that modern NA are not interested in slow heavy full keeled boats and said they are working on boat models to cross oceans *safely and fast*. You just have to look at their contemporary work, in what concerns modern passage makers, to understand what I mean.

Regards

Paulo


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## blt2ski

At the end of the day, it really only matters "IF" the boat design works for the type of sailing you wish to do, where you wish to do it etc. Be it a fin, full or something in between. if a one design, you will not have a lot of choice. If cruising, or ocean racing, look at the designs thru the years, in the past, lots of full keel's, more recent, fin's......

Not sure which is best. but from sailing my post fastnet IOR halfton, vs my step dads Bill Garden modern design plywood "Sea Bird" yawl. About the same wt, length, WL etc...... no way would I want to be sailing that thing in ANYTHING but calm water. It does not back up, does not go forward well either......then again, maybe it is the actual design of the boat!

At the end of the day, does it do what you want? if not, then it is the wrong design boat for you. If yes, then it is the right boat for you!

marty


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## skygazer

blt2ski said:


> At the end of the day, it really only matters "IF" the boat design works for the type of sailing you wish to do, where you wish to do it etc. Be it a fin, full or something in between.
> marty


But at the beginning of the day, I wish for more understanding, so I don't have to buy too many boats that are 'wrong' for me at the end of the day.


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## PCP

skygazer said:


> But at the beginning of the day, I wish for more understanding, so I don't have to buy too many boats that are 'wrong' for me at the end of the day.


There is only on answer for that. Get enough sailing experience (if you have not already) and try as many boats as you can, including heavy full keelers, medium fin keelers and light bulbed modern boats (a foil and a torpedo) and take your pick. You have also a big variety of hull shapes to chose.

Nothing will substitute personal experience to find the type of boat that will suit you. We all know that boats are compromises. Modern NA moved in a direction that they find that suits most tastes including their own, but that do not mean necessarily that your tastes will fit with the compromises they find better for a globally satisfying boat in what concerns seaworthiness, sailing performance, interior space and sea motion.

Regards

Paulo


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## BreakAwayFL

I was under the impression that a full keel also puts more weight lower in the water, which would make it more forgiving if you happen to have too much sail out...


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## Faster

BreakAwayFL said:


> I was under the impression that a full keel also puts more weight lower in the water, which would make it more forgiving if you happen to have too much sail out...


Way too many factors involved for that to be a true general statement. Some full keel boats have little draft and poor righting moment - others have adequate draft but use low density ballast like concrete.... and there are plenty of fin keel boats that are 'stiffer' than some full keelers.


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## PCP

Faster said:


> ...... and there are plenty of fin keel boats that are 'stiffer' than some full keelers.


And some that are stiffer than *any* full keeler.

Breakaway, Stiffness has not to do only with a low CG but also with form stability and that is particularly true with the stability that is used for sailing. Even in what regards final stability (over 60º) generaly a modern boat is more stiff (60 to 90º) than a full keeler.

It has to do with the shape of the stability curve. That is not true to all cases but generally an old full keeler (that are normally less beamy boats) has a more rounded curve with a smaller GZ (arm), a bigger AVS and less inverted stability, but between 60 and 90º the GZ curve values are remarkably smaller than on a modern boat. Its stability is mostly based on displacement, versus efficiency (bigger and better GZ curve) on a modern boat.

Regards

Paulo


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## Jeff_H

BryceGTX said:


> There really is nothing wrong with what he says, but it is incomplete. It has been well documented in 100 year old yacht design books that full keels have the advantage in big water because the rotation of the water in the wave causes the full keel boat to heel toward the wave rather than heel with the wave as with other keel designs.
> Bryce


I do think that there is something wrong with his statement beyond being incomplete and that you are mistaken when you say that _"the rotation of the water in a wave causes the full keel boat to heel toward the wave rather than heel with the wave as with other keel designs."_

Perhaps I can explain the basis of my comments and we might be able to reach agreement.

I will start with the first quote by Pvajko: 
_"The most important reason is that a full keel with its bigger surface area damps the rolling motion better." _

Here is the problem with that statement, dampening (the ability of a boat to dynamically to resist rotational motion) is directly proportional to a moment of inertia the amount of which results from the resistive force of the rotation and the distance that resistive force is from the instanteous rotational axis. In calculating a dampening moment, the force is a linear factor, but distance from the center of that force to the instanteous rotational axis is to the third power.

So that when you talk about the amount of dampening moment generated by a specific keel or keel type, the amount of area of the keel is a certainly significant factor, but the distance between the center of its rotational resistance and the instanteous rotational axis can be even more significant.

So, if we talk about the fin keels in the era when 'Seaworthiness' was written, these keels had perhaps a quarter of the surface area of a full keel on a similar length boat (and here I am not talking about the boats with long overhangs, an extreme cut away forefoot and raked rudder posts which had little more area than fin keels with separate rudders).

In the era that Marchaj wrote his book, between the shape of the fin keel, and the vertical height of the instanteous roll axis on fin keel boats of that era, the distance between the center of its rotational resistance and the instanteous roll axis was similar between a fin keel boat and a full keel boat and so the greater area of a full keel meant that there was significantly more dampening generated which is what Marchaj concludes.

But in the years since, several things have changed. Modern fin keel boat have greater draft, and differently shaped keels so that a greater portion of their area is deeper in the water, and their hull forms are such that their roll centers are slightly higher. That combination means that there can easily be a several time greater lever arm between the center of rotational resistance and the instanteous roll axis. So if we think that a modern keel has perhaps 20% of the area of a full keel but 2 or 3 times greater lever arm taken to the third power (in other words something like 8 to 27 times more leverage) it is easy to see that a modern fin keel boat could easily develop much higher dampening moments and so have better dampening than a full keel boat, making Pvajko statement incorrect that _"The most important reason is that a full keel with its bigger surface area damps the rolling motion better." _

In terms of Pvajko statement: _"While a fin keel performs much better in ideal conditions (flat water), stormy weather with big seas is a whole different story."_

I might agree with you that this is in part a true statement. All keels generate more lift in flat water than they do in disturbed conditions, but since fin keels tend to stall out much more quickly than longer chord keels, they lose a larger percentage of their lift, in other words, "stormy weather with big seas is a whole different story" for all keels but especially for fin keels.

But here is where that statement is misleading, in the years since 'Seaworthiness' the better modern fin keel shapes and corss sections have been developed to perform across broader range of conditions while losing a smaller percentage of their performance advantage. The impact of better dampening, the endplate effect of the bulb, foil shapes which more quickly establish flow and respond to it, means that fin keel boats may lose some small amount of their advantage over full keels in heavy going, depending on the course relative to the waves(i.e.beating upwind), but the modern fin keels still retain a significant performance and motion comfort advantage over a traditional full keel of similar length and displacement.

This last sentence is where it gets tough to make an 'apples to apples' comparison. In a broad general sense, full keeled boats tend to be heavier for their length (I know this is a 'duh statement) and have different hull forms than most modern fin keel boat. Because of that disparity it is easy to ascribe attributes to a full or fin keel which have nothing to do with the keel type and everything to do with the boat's design as a system. But even taking that into account, the statement seems to imply that a boat with a full keel will out perform a fin keel boat in heavy conditions, and while that may be true for some fin keels vs. full keels, it is not a universally accurate statement.

Regarding your statement: _"It has been well documented in 100 year old yacht design books that full keels have the advantage in big water because the rotation of the water in the wave causes the full keel boat to heel toward the wave rather than heel with the wave as with other keel designs."_

I personally don't know of any 100 year old yacht design book that says anything like that, but when I go back and look at my earliest copy of Skene's and Kunhardt, I find no reference of the sort so it might be helpful if you could provide a source for that. But even so, the idea that full keels heel toward a wave while fin keels rolls away flies in the face of what is known about the motion of boats in big waves.

What the science would suggest is that there are a number of factors which determine whether a boat heels into a big wave or away from the wave. First of all there is the rotational force. If you dissect the surface of a large wave, the water at the surface is moving faster than the water deeper in the wave nearer to the wave center. This progressive difference in speed between the surface and the center of the wave, means that the deeper the keel, the greater the sheer in the water speed acting on the boat trying to rotate the boat so that it heels away from the surface of the wave. Similarly, a keel with a greater side area will experience greater rotational force and so will have a greater tendency to heel away from the surface of the wave. But also, fin keels stall at very steep angles of attack, as might be experienced beam to on the side of big wave, thereby reducing the side force per unit area that the deeper keel may experience. This combination of factors means that in any specific case, either a fin keel or a full keel could experience the greater rotational force.

Resisting the roll force are stability and the roll moment of inertia. In the case of the fin keel vs. full keel discussion, modern fin keels, with their deeper drafts and densely concentrated ballast bulbs, generally generate much higher proportional stability than full keels. That was not the case at the time when 'Seaworthiness' was written but since modern designers have paid attention to the lessons of seaworthiness, and modern racing rules do not penalize stability as much as they did back then, it is true on the better modern fin keeled designs of today.

This greater stability means that a modern design would generate proportionately greater force to keep them upright and therefore greater force trying to heel the deck back toward the wave face.

The other factor, roll moment of inertia is similar to the discussion on dampening. The two factors impacting the amount of roll moment of inertia is weight and the distance between that weight and the instantaneous roll axis. While modern fin keeled boats tend to be lighter, they also tend to be deeper and taller so that due to their weigh distributions, they develop a disproportionately large roll moments of inertia.

In big waves, a large roll moment of inertia does two things, at the top of the wave, it delays the rotation of the boat relative to the rotational force. A good thing, but at the bottom of the wave, its greater stored kinetic energy, tends to cause it to get out of phase with angle of the wave face and continue to roll as the bottom of the wave flattens out so that there is a greater danger of dipping a spar in the water (never a good thing).

But to look at your statement fairly, we might also look at factors that have nothing to do with keel type. Modern designs tend to have greater form stability. Greater form stability tries to keep the waterline of the boat parallel to the wave face. At the top and middle of the wave, that would tend to roll the deck of the boat away from the face of the wave, the behavior that you describe in your quote. But that has nothing to do with the keel type. Two boats of equal form stability, similar draft and ballast stability, and roll moment of inertia would have the same angle of heel whether the boat had a full or fin keel.

And lastly, at the bottom of the wave, the boat with greater form stability would generate more righting force, remaining in sync with the wave surface and so would be less likely to dip a deck or spar and keep rolling.

What all of this suggests is that the specifics of the boat design and the conditions will determine whether it heels relative to the wave surface, but that the use of a fin keel or full keel is but one minor factor.



BreakAwayFL said:


> I was under the impression that a full keel also puts more weight lower in the water, which would make it more forgiving if you happen to have too much sail out...


Strictly speaking that is not always or even usually correct as it is written. While it is easier to keep the weight lower in a longer keel of an equal draft. But modern fin keels generally are deeper and have a bulb which makes it easier for them to carry their ballast with its vertical center lower than most full keels. But also there are a lot of factors that make a boat 'forgiving'. A modern fin keel boats relatively greater stability, lighter helm loads, more forgiving rig and sail handling gear, and more easily driven hull form might work in its favor 'forgivingness' wise. The typically better directional stability and lower vertical center of effort work in the favor of a typical full keel boats 'forgivingness'.

Respectfully,
Jeff


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## Rozz

i love my full keel, i have raced many of my friends and true, i am slower... but i always win cause i dont have the hour and half around the kelp beds lol
also on that note, i like to free/scuba dive and having the option to go to there is nice too. have we mentioned the dumb crab pots? hehe
ok beat the not getting hung up on stuff... i am willing to sacrifice the little speed for ease of mind and comfort, she rides well in most weather. im happy... thats what matters right?


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## Rozz

oh and forgot to mention, i havnt done to much with her worth talking about, but the p/o went all up and down the coast from Alaska to cabo and HI many times... so figure ill be ok


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## BryceGTX

PCP said:


> *safely and fast*


Any reasonable boat can cross the ocean. The difference between an IP and say a Jenneau is how you deal with a strong storm and rough water. That is what the discussion is about.

With an IP, you can simply heave to and you will be comfortable till the storm is over with. With a lightweight boat like a Jenneau, such a tactic could be suicidal. Such a boat must continue to move or be on a series drouge.

Racing boats are much the same as the Jenneau. Such boats have only hull moment. So they continue to move. However, race boats typically have a boat load of highly motivated sailors who better deal with fatigue. Contrast that with a couple on the cruising boat.

Now you can design any hull you wish, but it does not change the fundamental difference between these two types of boats. And it has nothing to do with what has happened in the last 30 years or the last 2000 years.
Bryce


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## BryceGTX

> Here is the problem with that statement, dampening (the ability of a boat to dynamically to resist rotational motion) is directly proportional to a moment of inertia the amount of which results from the resistive force of the rotation and the distance that resistive force is from the instanteous rotational axis. In calculating a dampening moment, the force is a linear factor, but distance from the center of that force to the instanteous rotational axis is to the third power.


Hello Jeff, I pretty much stopped reading after this paragraph. Damping has nothing to do with inertia. Inertia is related to the square of the distance and the force is a function of acceleration. Damping is related to area and the moment is proportional to distance. The force is a function of velocity.

Bryce


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## BryceGTX

Faster said:


> there are plenty of fin keel boats that are 'stiffer' than some full keelers.


I would say in general that most any newer flat bottom, wide beam fin keel is more stiff than most any full keel. That is exactly the characteristic of such boats. Heavy full keel boats are typically not stiff. However, heavy full keel invariably have considerably more mass righting moment. That's what makes them so much better in rough water.
Bryce


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## PCP

Jeff_H said:


> ... dampening (the ability of a boat to dynamically to resist rotational motion) is directly proportional to a moment of inertia the the amount of which results from the resistive force of the rotation and the distance that resistive force is from the instanteous rotational axis....


Hi Jeff,

There are other factors that contribute to dynamic stability and I don't think that one is the more important. Really important is everything that contributes to dissipate the wave energy in kinetic lateral movement and detrimental is everything that contributes to transform that energy in a rotational movement.

I would say that the main factors that contribute to allow the dissipation of energy through a lateral movement are a small area of submersed surface, a small freeboard and a big righting moment (not necessarily at big angles of heel because when boats slide sideways in a wave the heel is not much) and a low inertia.

Regarding inertia and roll moment of inertia, let's consider two boats with the same positive area under the RM curve, and therefore needing the same energy to be capsized. One is a long keeler, small draft, narrow heavy weight boat the other one is a beamy light boat with a big draft and all the ballast on a bulb at the end of a fin keel.

As I had said before the dynamic behavior of these boats when hit by a breaking wave will be very different in what regards the capacity to dissipate the wave energy moving sideways, but let's consider that the full keeler would not trip in its keel, that the extra surface would not have a damping effect on the rotational movement and that the low mass and small under water surface would not permit the lighter boat to move much more easily sideways.

Let's consider that the same amount of energy of the wave that hits the boats results in a rotational movement for both boats.Both boats require the same energy to be capsized so in what regards the results (capsizing or not) the effect would be the same but the kind of movement due to inertia would be very different.

The heavier boat would start to roll much more slowly but because it has much more inertia once started the rolling movement it would be much harder to stop it. On the lighter boat the roll movement will be faster but will be also stopped faster because the inertia is much smaller. Both boats will roll to the same point but the duration of the roll movement (to capsize at 90º and back to its feet) will be much longer on the heavier boat.

We could say that the slower movement is a more comfortable one but the fact is that in what regards seaworthiness the heavier boat will be much more time deeply heeled, exposing its side much longer to another breaking wave that will catch him with little stability left and therefore will have potentiated effects, resulting probably in a capsize.

That's why I think roll moment of inertia is not a determinant factor in Dynamic stability and that its effect in Dynamic stability effectiveness is many times hugely overrated.

Regards

Paulo


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## skygazer

To use water analogies: things are "getting deep" in this discussion, and I find more and more that it's "over my head"!  

My copy of the book "Seaworthiness" has been shipped, perhaps if I can digest some of that, I'll at least have a handle on the 30 yr. old side of the discussion.


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## PCP

skygazer said:


> To use water analogies: things are "getting deep" in this discussion, and I find more and more that it's "over my head"!
> 
> My copy of the book "Seaworthiness" has been shipped, perhaps if I can digest some of that, I'll at least have a handle on the 30 yr. old side of the discussion.


Why to pay or wait for it? As I have said it is an old book and has many old books it can be downloaded for free:

Seaworthiness: The Forgotten Factor - Free eBooks Download

Regards

Paulo


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## Jeff_H

BryceGTX said:


> Hello Jeff, I pretty much stopped reading after this paragraph. Damping has nothing to do with inertia. Inertia is related to the square of the distance and the force is a function of acceleration. Damping is related to area and the moment is proportional to distance. The force is a function of velocity.
> 
> Bryce


Bryce,

You apparently are mistaking simple 'moments' and simple 'inertia' for 'moments of inertia' the term that I used in the quote from my explanation.

As I am using the term 'Moment of Interia' I am using the term defined as, "In classical mechanics, moment of inertia, also called mass moment of inertia, rotational inertia, polar moment of inertia of mass, or the angular mass, is a measure of an object's resistance to changes to its rotation. It is the inertia of a rotating body with respect to its rotation. The moment of inertia plays much the same role in rotational dynamics as mass does in linear dynamics, describing the relationship between angular momentum and angular velocity, torque and angular acceleration, and several other quantities."

When talking about dampening, the resistance to changes in rotation is not just the inertial mass of the object, but the resistive forces of the side force of water against the keel, and the side force of the wind against the sails, times the distance to the axis squared. But since the unit force is proportionate to the radius of the rotation, the formula for calculating roll moment of interia due to the keel, the distance between the center of the force and roll axis is to the third power.


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## skygazer

PCP said:


> Why to pay or wait for it? As I have said it is an old book and has many old books it can be downloaded for free:
> 
> Seaworthiness: The Forgotten Factor - Free eBooks Download
> 
> Regards
> 
> Paulo


Thanks Paulo, but too late for me, it's already paid for and on the way. At least I'll be able to highlight and mark it up, which always helps me to key in on and summarize important ideas.


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## Oregonian

I certainly understand the theoretical advantages of the modern design but I question whether those advantages apply in at least one very common scenario. If this boat is 32 feet and used for very long distance cruising, ie a dinghy or two, 3 or 4 anchors and rodes, 40 days of food for 2, etc.etc, is it still going to be just as stable and fast as when it was test sailed by the owner? Personally, in my opinion, this modern design is going to prove to be slower and MUCH less stable than had it been designed a little heavier in the first place and with a little more boat in the water. 
I once counted the rolls of 2 very different designs as they were sailing DW off Baja. One, a full keel 32, the other a modern 36. The full keel 32 rolled exactly 30% less than the 36. That is, the 36 rolled 100 times during the 32’s 70 times. Both boats rolled at what seemed the same angle. The 32 was sailing about 1/4k faster. Are future cruisers going to have to give up comfort for the modern design or go much longer in WL to get reasonable comfort?


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## Jeff_H

Oregonian said:


> I certainly understand the theoretical advantages of the modern design but I question whether those advantages apply in at least one very common scenario. If this boat is 32 feet and used for very long distance cruising, ie a dinghy or two, 3 or 4 anchors and rodes, 40 days of food for 2, etc.etc, is it still going to be just as stable and fast as when it was test sailed by the owner? Personally, in my opinion, this modern design is going to prove to be slower and MUCH less stable than had it been designed a little heavier in the first place and with a little more boat in the water.


I completely agree with what you are saying if we compare boats based solely on length on deck. If the comparison is two equal length boats that are equally loaded, one a traditional long waterline relative to LOA, heavy L/D boat, whether full keel or some partially cut away keel form, and the other a more modern equal length boat, the newer boat will not be able carry as much weight in gear and consumables without seriously compromising performance and seaworthiness. But also, since design loads on the hull and rig are proportionate to the displacement of the boat, when equally loading these two boats a lighter modern design will be loaded proportionately more as compared to its design displacement and so would end up being a comparatively less robust boat when loaded to the max loading of the equal length heavy d/l cruiser.

It is for this reason that I have always suggested that a better way of comparing offshore boats is to compare boats of equal empty displacement rather than boats of equal length on deck or waterline. In that comparison, within reason, the longer boat of equal displacement will generally offer better performance across a wide windspeed range, offer better motion comfort and seaworthiness, be easier to handle, have better carrying capacity without impacting handling or seaworthiness and have roughly similar operating costs.



Oregonian said:


> I once counted the rolls of 2 very different designs as they were sailing DW off Baja. One, a full keel 32, the other a modern 36. The full keel 32 rolled exactly 30% less than the 36. That is, the 36 rolled 100 times during the 32's 70 times. Both boats rolled at what seemed the same angle. The 32 was sailing about 1/4k faster. Are future cruisers going to have to give up comfort for the modern design or go much longer in WL to get reasonable comfort?


Anecdotally I can imagine how this would be true more often than not. Similar to the discussion above, a heavier (D/L) displacement boat will typically offer a slower roll rate, which can be a very good thing in a comparative short chop or in long wave length ocean conditions.

Depending on the wave frequency, and the weight and bouyancy distribution of the two boats, the heavier boat may also roll through a narrower roll angle as well.

But if we compare boats of equal displacement, one longer than the other, the longer boat will generally offer a similar roll rate, but if the boat is a modern design which has been properly designed for motion, the roll angle should be smaller and the edges of the roll more gentle. But also the collisions with waves when beating and close reaching should also produce less hobby-horsing and a softer collision with each wave.

On the other hand, depending on the wave frequency, and relatve speeds of the boats, the longer boat for the same displacement may not fare so well with regards to heave. Typically a longer boat with a smaller D/L, when encountering a single large wave or a widely spaced wave train, will heave at closer to the speed of the wave than a boat with a heavier D/L giving the heavier boat a much more comfortable heave motion in those conditions.

On the other hand, the heavier D/L advantage can get lost in a repetitive, closer spaced wave train, where the inertia of the heavier boat can take it our of sync with the wave train and so cause it to hit harder at the trough and peak of the wave resulting in a less comfortable motion in a narrow range of conditions.

Respectfully,
Jeff


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## Faster

Seems, too, that boats with hard bilges and high form stability are going to be more likely to 'follow the sea surface' in a beam sea and therefore 'roll' more dramatically as a wave passes underneath.


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## Oregonian

Those are both good and thoughtful answers. I agree. Thankyou
It seems unfortunate though, in my opinion, that the smaller boats are getting short changed by the modern approach to sailboat design. Yes, they are producing faster and lighter boats in the 30 foot range, but not faster and safer long range cruisers in that size. The modern hull forms and their attached appendages cannot duplicate the speed and safety when ladened. Something that most marketers are not telling the buyers. There is a simple explanation why the lowly Westsail 32 is slow compared to some boats around the buoys. There is also a (slightly less) simple explanation why the same W-32 is faster than said boats when they are used for long distance voyaging. There are sailors out there who are truly looking for that smaller “go anywhere”, live aboard, cruiser. That is, under 35 feet. A Westsail 32, admittedly a 40 foot boat, is attractive partly because it is “smaller”. 
I personally, would like to see the designers, producers, and marketers spend a little more time applying the modern technology to a better, safer, “go anywhere”, cruiser that doesn’t fall flat on its face in performance, comfort, and safety when fully, or over fully, ladened, or, when it hits the bottom in the lagoon at Aitutaki. It would also be appreciated if these same people told the truth about how cruising performance will be different than racing performance, even with the modern, fast, light weight boats.
Full vs. fin keel? I prefer what I have. The best that a designer can do is to design the best boat for what it is really going to be doing, at its extremes. And remember that there are people inside.
Thanks again

After thought: Would it have been more appropriate to have put this post in the "Shameless Plug" thread?


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## PCP

Oregonian said:


> Those are both good and thoughtful answers. I agree. Thankyou
> It seems unfortunate though, in my opinion, that the smaller boats are getting short changed by the modern approach to sailboat design. Yes, they are producing faster and lighter boats in the 30 foot range, but not faster and safer long range cruisers in that size. The modern hull forms and their attached appendages cannot duplicate the speed and safety when ladened. Something that most marketers are not telling the buyers. There is a simple explanation why the lowly Westsail 32 is slow compared to some boats around the buoys. There is also a (slightly less) simple explanation why the same W-32 is faster than said boats when they are used for long distance voyaging. There are sailors out there who are truly looking for that smaller "go anywhere", live aboard, cruiser. That is, under 35 feet. A Westsail 32, admittedly a 40 foot boat, is attractive partly because it is "smaller".
> I personally, would like to see the designers, producers, and marketers spend a little more time applying the modern technology to a better, safer, "go anywhere", cruiser that doesn't fall flat on its face in performance, comfort, and safety when fully, or over fully, ladened, or, when it hits the bottom in the lagoon at Aitutaki. It would also be appreciated if these same people told the truth about how cruising performance will be different than racing performance, even with the modern, fast, light weight boats.
> Full vs. fin keel? I prefer what I have. The best that a designer can do is to design the best boat for what it is really going to be doing, at its extremes. And remember that there are people inside.
> Thanks again
> 
> After thought: Would it have been more appropriate to have put this post in the "Shameless Plug" thread?


I think Jeff had already replied to that saying that makes sense to compare boats by its weight even if I think that weight by weight a modern boat is more seaworthy. Perhaps it still misses something to make things more clear and that is that makes also sense to compare boats by weight in what regards price.

So why should today designers be interested in making a very small seaworthy boat, like a Westsail 32, if for the same price they can make a 36/38 light modern boat that will have the same seaworthimess, a better wave passage (much longer LWL), will be much faster and will offer the same load capacity and much more interior space?

who between the two boats would chose the small heavy one? almost anybody

Regards

Paulo


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## Jeff_H

Oregonian said:


> It seems unfortunate though, in my opinion, that the smaller boats are getting short changed by the modern approach to sailboat design. Yes, they are producing faster and lighter boats in the 30 foot range, but not faster and safer long range cruisers in that size. The modern hull forms and their attached appendages cannot duplicate the speed and safety when ladened. Something that most marketers are not telling the buyers. There is a simple explanation why the lowly Westsail 32 is slow compared to some boats around the buoys. There is also a (slightly less) simple explanation why the same W-32 is faster than said boats when they are used for long distance voyaging. There are sailors out there who are truly looking for that smaller "go anywhere", live aboard, cruiser. That is, under 35 feet. A Westsail 32, admittedly a 40 foot boat, is attractive partly because it is "smaller".
> I personally, would like to see the designers, producers, and marketers spend a little more time applying the modern technology to a better, safer, "go anywhere", cruiser that doesn't fall flat on its face in performance, comfort, and safety when fully, or over fully, ladened, or, when it hits the bottom in the lagoon at Aitutaki. It would also be appreciated if these same people told the truth about how cruising performance will be different than racing performance, even with the modern, fast, light weight boats.
> Full vs. fin keel? I prefer what I have. The best that a designer can do is to design the best boat for what it is really going to be doing, at its extremes. And remember that there are people inside.


To a very great extent I agree with what you are saying about the lack of decent small offshore cruisers being designed and constructed. At some level, it is easy to understand that the average sailor, at least in the US, neither needs or wants a purpose designed and built distance cruiser, and so it sort of makes sense that most of the boats being designed and built are at best optimized as coastal cruisers or racers, and at worst, value-oriented, nearly disposable family weekenders.

But as you say, I think that it is a shame that we don't see designers developing and builders constructing purpose-built, offshore capable, distance cruisers, either of traditional designs or of a more modern design concept. There was a time in the 1970's and early 1980's when there was a genuine effort to develop wholesome, ocean capable designs, and it produced designs (like the Valiant 40, Esprit 37, Tayana 37, Pacific Seacrafts, and Westsails) which are still basically good boats for that purpose today. But in my opinion, it seems like it has been decades since there has been a serious effort to develop and build a new dedicated, purpose built, offshore capable design. ( I know that line has the Island Paket crowd are looking for a rope to hang me)

There has always been a price to be paid for a boat being purpose built for offshore use. As you know, and I agree to withstand the abuse the boat needs some combination of simple robust construction, or carefully engineered structure with large saftey factors designed in. It needs robust and reliable hardware. Lockers and tanks need to be secure during a roll over. There needs to be sturdy and convenient hand and foot holds. The rig needs to be able to quickly adapt from light air to heavy air. There needs to lagre enough tanks to support the boat for long passages and infrequent ports. The keel needs to be able to withstand a hard grounding or an impact with a semi floating object, and the rudder needs to be protected.

When you get done with all of that, you end up with a boat that is very expensive for its displacement, and even more so for its length. And since there is a limited market for boats like these, and there is a large market of older designs in servicable condition, I can understand why almost no new offshore designs have hit the market.

In an earlier discussion someone asked me to give an example of a "modern offshore cruiser' that I liked. I mentioned "Firefly' which was the prototype for the Morris 45 but noted that I think this is too large a boat for my taste and I really do not like the large portlights or oversized cockpit for offshore use. Someone objected that even for a 45 footer this is a wildly expensive boat and I agreed, but I also think that is the point, to achieve a new boat which is both rugged, and capacious, and still capable of being a good offshore boat takes careful thought and a lot of money these days.

In the case of more traditional designs, the 'lots of careful thought' came from centuries of trial and error. When you talk about more modern designs, it really requires a lot of applied skill and few clients are willing to pay the cost of time required to apply that skill, let alone pay for the finished product.

When it comes to cruising on the cheap, there are few decent choices left out there. Many of the boats which I might have recommended 10-15 years ago were rare enough even then that the few examples available have become worn out and so are no longer good candidates.

And I find it disconcerting when I see people advocating old, short waterline, short keel, attached rudder, cruiser- racers as being good offshore capable cruisers. One of the strengths of the type of boat that you advocate is that they have very long water lines relative to their lengths on deck. This helps with motion comfort and carrying capacity. Such is not the case with the CCA and IOR based cruiser-racers of the 1960's and 1970's taht I often see advocated as offshore cruisers.

Enough for this lovely spring afternoon. I am going sailing.
Cheers,
Jeff


----------



## Oregonian

PAULO, Thanks for responding. Your arguments are good but, in my opinion, they leave something very important out. COMFORT Certainly this is relative but it is easily the breaking point for many cruisers. Myself included. The 38 foot boat that the designers want people to buy instead of a heavy 32 footer will not have the same motion comfort. This is only one example of a hundred: On a delivery return from Hawaii on a very modern 46 foot high performance, racer/cruiser, We were pounding so horribly that we had to slow the boat way down and move much farther off course. We were 4 human beings and wanted to live. In the exact same conditions a boat like a Westsail 42/43, which is much heavier would have continued right on course, with a VMG exceeding that of the fast 46 footer. Yes, I agree, the racing crew would probably have just hung on for another 800 miles until things improved.
I do not accept that the designers should be telling me what I want. Concerning the smaller sizes of long distance voyaging boats, the modern designs are falling way short of of their promise. The theory is good but it doesn’t work out. I have yet to see it. If a boat has just the right Shape for a given displacement, then that same boat has the wrong shape when its displacement was altered because of the necessary stores and equipment for long range voyaging. This is, of course, Much more true of the smaller boats.
At this point in this post I offer one more disagreement with your comments. SPEED I must ask you, how much faster is that modern 38 footer going to be going than the heavy 32 footer that the designers want us to buy? (don’t forget to store the dinghy on that 38 footer) In my opinion, and I have sailed both, the real world answer is, very little, IF at all.
Just one more subject: STRENGTH Yes, technology can handle that problem. But the manufacturers are not. Where I live it is not uncommon to get a little twisted when maneuvering against the wind and current. When the heavy boat hits the dock. The dock may break. When the light weight modern boat hits the dock there is frequently a hole left in the hull. S*** happens.
Full vs. fin keel? On the smaller boats the better designers will use what is the best.

JEFFH, I have not read all 5418 of your posts but I have read Many. I think I like that last one the best. Thanks


----------



## Brent Swain

My long fin keel or twin keel steel boats are anything but expensive for their displacement. 
Many of those older , short keel with rudder attached boats have been drastically improved, by taking the rudder off the keel and replacing it with a skeg hung rudder six feet further aft. I did that on my first boat,a 36 ft pipe dream sloop, designed by Kinny , with a drastic improvement in control. A 1958 design with the same improvements has won the Shark Spit regatta for the last three years in a row. The owner said "If anyone does the same thing on an Alberg 37, I'll never catch him.
Well raked , short keel hung rudders tend to act as drogues.


----------



## PCP

Oregonian said:


> .. The 38 foot boat that the designers want people to buy instead of a heavy 32 footer will not have the same motion comfort.


Motion comfort has to do also with LWL. A bigger boat has a more comfortable wave passage. Regarding the type of motion of an heavy boat versus a light one, well it is debatable, some like the big slow pitching of the old boats, some prefer the faster but less ample movements of a modern boat.

It is for each one to chose its preference.



Oregonian said:


> This is only one example of a hundred: On a delivery return from Hawaii on a very modern 46 foot high performance, racer/cruiser, We were pounding so horribly that we had to slow the boat way down and move much farther off course.


Of course, in what concerns going upwind a fast boat is always more uncomfortable than a slow boat. If you cannot take the pounding that power and speed can induce, or just don't want to, you have just to go slower and it seems it was what you have done. A fast boat can go slower, a slower boat cannot go faster



Oregonian said:


> Concerning the smaller sizes of long distance voyaging boats, the modern designs are falling way short of of their promise. ...
> At this point in this post I offer one more disagreement with your comments. SPEED I must ask you, how much faster is that modern 38 footer going to be going than the heavy 32 footer that the designers want us to buy? (don't forget to store the dinghy on that 38 footer) In my opinion, and I have sailed both, the real world answer is, *very little, IF at all.*


You can only be kiding Between a westsail 32 and a good light cruiser like a Salona 38? Maybe 4 days in an Atlantic crossing? Maybe more if the Westsail has bad luck and the wind is weak. On coastal cruising without trade winds the difference will be a lot bigger.

Regards

Paulo


----------



## skygazer

Jeff_H said:


> To a very great extent I agree with what you are saying about the lack of decent small offshore cruisers being designed and constructed. At some level, it is easy to understand that the average sailor, at least in the US, neither needs or wants a purpose designed and built distance cruiser, and so it sort of makes sense that most of the boats being designed and built are at best optimized as coastal cruisers or racers, and at worst, value-oriented, nearly disposable family weekenders.
> 
> But as you say, I think that it is a shame that we don't see designers developing and builders constructing purpose-built, offshore capable, distance cruisers, either of traditional designs or of a more modern design concept. There was a time in the 1970's and early 1980's when there was a genuine effort to develop wholesome, ocean capable designs, and it produced designs (like the Valiant 40, Esprit 37, Tayana 37, Pacific Seacrafts, and Westsails) which are still basically good boats for that purpose today. But in my opinion, it seems like it has been decades since there has been a serious effort to develop and build a new dedicated, purpose built, offshore capable design. ( I know that line has the Island Paket crowd are looking for a rope to hang me)
> 
> There has always been a price to be paid for a boat being purpose built for offshore use. As you know, and I agree to withstand the abuse the boat needs some combination of simple robust construction, or carefully engineered structure with large saftey factors designed in. It needs robust and reliable hardware. Lockers and tanks need to be secure during a roll over. There needs to be sturdy and convenient hand and foot holds. The rig needs to be able to quickly adapt from light air to heavy air. There needs to lagre enough tanks to support the boat for long passages and infrequent ports. The keel needs to be able to withstand a hard grounding or an impact with a semi floating object, and the rudder needs to be protected.
> 
> When you get done with all of that, you end up with a boat that is very expensive for its displacement, and even more so for its length. And since there is a limited market for boats like these, and there is a large market of older designs in servicable condition, I can understand why almost no new offshore designs have hit the market.
> 
> In an earlier discussion someone asked me to give an example of a "modern offshore cruiser' that I liked. I mentioned "Firefly' which was the prototype for the Morris 45 but noted that I think this is too large a boat for my taste and I really do not like the large portlights or oversized cockpit for offshore use. Someone objected that even for a 45 footer this is a wildly expensive boat and I agreed, but I also think that is the point, to achieve a new boat which is both rugged, and capacious, and still capable of being a good offshore boat takes careful thought and a lot of money these days.
> 
> In the case of more traditional designs, the 'lots of careful thought' came from centuries of trial and error. When you talk about more modern designs, it really requires a lot of applied skill and few clients are willing to pay the cost of time required to apply that skill, let alone pay for the finished product.
> 
> When it comes to cruising on the cheap, there are few decent choices left out there. Many of the boats which I might have recommended 10-15 years ago were rare enough even then that the few examples available have become worn out and so are no longer good candidates.
> 
> And I find it disconcerting when I see people advocating old, short waterline, short keel, attached rudder, cruiser- racers as being good offshore capable cruisers. One of the strengths of the type of boat that you advocate is that they have very long water lines relative to their lengths on deck. This helps with motion comfort and carrying capacity. Such is not the case with the CCA and IOR based cruiser-racers of the 1960's and 1970's taht I often see advocated as offshore cruisers.
> 
> Enough for this lovely spring afternoon. I am going sailing.
> Cheers,
> Jeff


Jeff H., OK, I punched the "Like" button, but I have to also say that I really enjoyed your thoughtful post.



PCP said:


> Edited: A fast boat can go slower, a slower boat cannot go faster
> Regards
> 
> Paulo


Great one liner!


----------



## Oregonian

PAULO, I appreciate your participation concerning this Full vs. Fin keel discussion. Once again, however, I believe you have made a misleading statement. And No, I am not kidding. The Salona 38 does not appeal at all to me. I would much rather have an Alajuela 38 if I had to go that large, for long distance sustained voyaging. Do you not think that the Salona 38’s performance might be compromised just a little when carrying a dinghy (I carry 2 full dinghies when cruising on my 32 with my wife), 3 proper anchors each with 300ft rodes, plus 3000# of additional stuff? Maybe, also a dodger, solar panels, and definitely a little more battery capacity? Why carry so much? Because that is what people do, and need, if they are doing long distance sustained cruising. It is my opinion that your Salona 38 when loaded like a real cruiser will sail significantly worse than what you think, or are just saying.

PAULO: “A fast boat can go slower. A slow boat cannot go faster”
OREGONIAN: “A fast boat cannot go fast when heavily loaded. It becomes slower than the slow boat”

For anyone still interested in this discussion, a few (certainly not all) very good ocean voyaging full keel boats that really would surprise the critics are: The whole line of Cape George cutters, the Alajuela 38, the Westsails, the Bristol Channel Cutter and perhaps the best of all, the Falmouth Cutter at 22ft.

And one last thing: the continual reference to needing the “Trade Winds” to move or not being able to go to weather is totally a bogus statement on your part and the other critics. All the boats mentioned have no trouble in light winds or going to weather, if the owners want them to and have the equipment. All those boats can get the job done just fine.


----------



## mitiempo

Boats price (when new) by the pound, assuming similar level of equipment.

So lets compare boats by their displacement.

Westsail 32 displacement 19,528 lbs

Beneteau first 42 displacement 18,600 lbs

Pounds /inch immersion

Westsail 32 1064 lbs

Beneteau First 42 1712 lbs

Isn't that a fair comparison?

The Alajuela 38 displaces 27,000 lbs and a fairer comparison would be a boat like the Bavaria 50 at a similar weight.

I don't think the First or Bavaria would be upset that much by the weight carried by the Westsail or Alajuela, given their longer waterlines and much less immersion under the same weights.


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## benjmin

This Is Great! 

All the smart people are posting info on full and fin keels in this thread.

Perhaps they are all still subscribed and could expand their info. I looked around a whole bunch but could not afford a full keel. I have yet to sail my boat because it is still being painted. I was wondering what to expect from what i believe are called 3/4 keel like the one on my boat? Is there a positive side to a keel like mine?  

Documentation says my draft is 5'6" 
36' LOA Vessel weighing 16,500lbs with a beam of 12'4"

I am hull #1 of 2 i believe. Created by Squadron Yachts of Bristol RI in 1981 in case anyone was curious where i got a boat they hadn't seen before.


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## PCP

Nice boat

Regards

Paulo


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## BryceGTX

Jeff_H said:


> Bryce,
> 
> You apparently are mistaking simple 'moments' and simple 'inertia' for 'moments of inertia' the term that I used in the quote from my explanation.


No... I was also referring to moment of inertia. Like most, I use inertia to refer to the moment of inertia when dealing with rotary motion.



> When talking about dampening, the resistance to changes in rotation is not just the inertial mass of the object, but the resistive forces of the side force of water against the keel, and the side force of the wind against the sails,


Damping only refers to the velocity factor (angular). Inertia provides no damping. The equation below relates damping force and inertia force. Both are angular, the inertia is the moment of inertia around the axis of rotation.

Actual angular velocity may be a polynomial in velocity.

F = damping * d(theta)/dt + inertia * d^2(theta)/dt

The resistive forces you refer to is damping.


----------



## BryceGTX

PCP said:


> There are other factors that contribute to dynamic stability and I don't think that one is the more important. Really important is everything that contributes to dissipate the wave energy in kinetic lateral movement and detrimental is everything that contributes to transform that energy in a rotational movement.


This completely ignores the most significant point that a properly designed rough water boat deals with rough water by reducing the heeling, not necessarily by dissipating energy better.



> Regarding inertia and roll moment of inertia, let's consider two boats with the same positive area under the RM curve....


It is illogical to talk about a static stability curve when you put a boat on waves. Because a static stability curve only describes a boats RM on flat water. And of course moment of inertia only has significance with angular acceleration.. So a discussion of static curves and inertia is not appropriate.
Bryce


----------



## BryceGTX

benjmin said:


> This Is Great!
> 
> All the smart people are posting info on full and fin keels in this thread.
> 
> Perhaps they are all still subscribed and could expand their info. I looked around a whole bunch but could not afford a full keel. I have yet to sail my boat because it is still being painted. I was wondering what to expect from what i believe are called 3/4 keel like the one on my boat? Is there a positive side to a keel like mine?
> 
> Documentation says my draft is 5'6"
> 36' LOA Vessel weighing 16,500lbs with a beam of 12'4"
> 
> I am hull #1 of 2 i believe. Created by Squadron Yachts of Bristol RI in 1981 in case anyone was curious where i got a boat they hadn't seen before.


The design of your boat has all the traits of an excellent rough water boat. Looking straight on from the bow, we see the deep v-hull design that provides much lower hull righting moment than the newer flat bottom boats. Lower hull righting moment means that this boat will heel considerably less on a wave than a flat bottom boat. The lower hull righting moment is compensated by a heavier keel. So in the end, your boat may have the same or more righting moment than the flat bottom boat.

The bow is lavishly raked along with hull sides to provide progressively increasing bouancy as the hull dives into a wave. Such a bow is well known to reduce the tendency of the bow to boring through the wave. Which is dangerous.

The deep v hull also provides a parting action to the water as the boat comes off a large wave dramatically reducing pounding when going into seas.

The long keel provides stability as has been pointed out. Interestingly enough you rudder is hung further aft, no doubt providing very good directional control. Not all boàts hang the rudder so far back.

The cost is that this boat may be a bit slower than the typical flat bottom boat. But your boat is going to be so much more comfortable in rough water. On the other hand the speed of this boat will be highly dependent on how much sail you put up. So you should not consider that this boat is inherently slow because of its hull design. Sail area will have a huge impact.
Bryce


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## SimonV

The best keel and rudder set up are the ones that are under the boat you love and can afford. If all the boats were the same....blah blah blah.


----------



## mdi

mitiempo said:


> Boats price (when new) by the pound, assuming similar level of equipment.
> 
> So lets compare boats by their displacement.
> 
> Westsail 32 displacement 19,528 lbs
> 
> Beneteau first 42 displacement 18,600 lbs
> 
> Pounds /inch immersion
> 
> Westsail 32 1064 lbs
> 
> Beneteau First 42 1712 lbs
> 
> Isn't that a fair comparison?


Carl's Sail Calculator is a useful comparison tool as well.


----------



## skygazer

BryceGTX said:


> The design of your boat has all the traits of an excellent rough water boat. Looking straight on from the bow, we see the deep v-hull design that provides much lower hull righting moment than the newer flat bottom boats. Lower hull righting moment means that this boat will heel considerably less on a wave than a flat bottom boat. The lower hull righting moment is compensated by a heavier keel. So in the end, your boat may have the same or more righting moment than the flat bottom boat.
> 
> The bow is lavishly raked along with hull sides to provide progressively increasing bouancy as the hull dives into a wave. Such a bow is well known to reduce the tendency of the bow to boring through the wave. Which is dangerous.
> 
> The deep v hull also provides a parting action to the water as the boat comes off a large wave dramatically reducing pounding when going into seas.
> 
> The long keel provides stability as has been pointed out. Interestingly enough you rudder is hung further aft, no doubt providing very good directional control. Not all boàts hang the rudder so far back.
> 
> The cost is that this boat may be a bit slower than the typical flat bottom boat. But your boat is going to be so much more comfortable in rough water. On the other hand the speed of this boat will be highly dependent on how much sail you put up. So you should not consider that this boat is inherently slow because of its hull design. Sail area will have a huge impact.
> Bryce


Bryce, nice discussion of the attributes of that beautiful looking (and clean!) boat. Thank you. The combination of the long keel, but with an aft rudder, is interesting.

And just when I was worrying that you were here to argue rather than debate - I'm sure you have seen many threads destroyed that way. 



SimonV said:


> The best keel and rudder set up are the ones that are under the boat you love and can afford. If all the boats were the same....blah blah blah.


True, but when not sailing, thinking about and shopping for sailboats is enjoyable. "Thinking and shopping" requires insights into how different types of boats may behave in differing conditions.

This is an excellent thread, with lots of good discussion.


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## PCP

BryceGTX said:


> This completely ignores the most significant point that a properly designed rough water boat deals with rough water by reducing the heeling, not necessarily by dissipating energy better.
> ....


There is nothing that come close to reducing heeling as beam in a boat. Tank testings showed a direct relations between beam and the size of the breaking wave needed to capsize the boat.

Regards

Paulo


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## PCP

Hey, I was just talking about this and we have here just a demonstration of what I was saying about inertia and the importance of returning fast to its feet after a capsize, to reduce the chances to be hit by a second wave when the boat is laying down:

(posted on interesting sailboats thread)



G1000 said:


>


Great images. Those are really big breaking waves

Outstanding the speed that this boats can return to its feet after being capsized, even with a lot of sail out That was a double hit, if the boat had a lot of inertia (a lot of weight for the same RM) and was still capsized when it was hit by the second wave, the story could be other. We can also see clearly the boat going sideways and rotating dissipating with movement the wave energy (look at the clouds) otherwise than with a rolling movement.

Regards

Paulo


----------



## BryceGTX

PCP said:


> There is nothing that come close to reducing heeling as beam in a boat. Tank testings showed a direct relations between beam and the size of the breaking wave needed to capsize the boat.
> 
> Regards
> 
> Paulo


You are correct that beam width is the best way to reduce heeling angle due to winds. Because it increases the hull righting moment. And I have said this earlier on this thread. However, excellent rough water boats are built with moderate beams with a more v-shaped hull design which actually reduces the effects of beam and such boats have significant mass in the keel.

No doubt, to meet some race boat criteria, someone has produced the results you describe. Your video shows exactly the problem with wide beam racing boats that have little mass righting moment. That is they heel with the seas. Such boats are easily the worst rough water boat anyone could design.

Here is a blurb from a yacht design book from the 1800s that pretty much summarizes what we know even to this day. Vessels with wide beams are most affected by wave motion. I think this is pretty much common knowledge.
Bryce


----------



## BryceGTX

PCP said:


> That was a double hit, if the boat had a lot of inertia (a lot of weight for the same RM) and was still capsized when it was hit by the second wave, the story could be other. We can also see clearly the boat going sideways and rotating dissipating with movement the wave energy (look at the clouds) otherwise than with a rolling movement.
> 
> Regards
> 
> Paulo


If it was a properly designed rough water boat, it would have hardly heeled at all during either of the waves. Interestingly enough, rough water boats do not necessarily have high inertia. The predominant inertia from a sailboat invariably comes from its standing rigging. Not from its keel. We have to be careful not to confuse weight with inertia. Although no doubt, a light weight mast on a 10 Million dollar sail boat is bound to have less inertia than any cruising boat.

What you are seeing in the video is the racing boats return to vertical due to its incredibly high hull righting moment. Thats what you get with light weight and a wide beam. The way you pay for this incredible high RM is that the boat heels heavily in a wave as the video shows.

Here is a picture what a boat with only hull righting moment does on a wave. And then how a rough water boat deals with waves.

Your video shows exactly what I was describing earlier in this thread. That is a racing boat load of motivated sailors will hammer through rough seas to finish a race. A cruising couple will hunker down below till the storm is over.
Bryce


----------



## skygazer

PCP said:


> Outstanding the speed that this boats can return to its feet after being capsized, even with a lot of sail out That was a double hit, if the boat had a lot of inertia (a lot of weight for the same RM) and was still capsized when it was hit by the second wave, the story could be other. We can also see clearly the boat going sideways and rotating dissipating with movement the wave energy (look at the clouds) otherwise than with a rolling movement.
> 
> Regards
> 
> Paulo


Paulo, when I watch the video it appears there is a time edit between the first two waves, so there is no way to tell how long the interval is. Also, when I look at the clouds it looks like the boat is rounding up, I don't see the sideways motion.

Am I correct in thinking you mean that the narrow deep keel allows sideways slipping down the wave face, rather than tripping on a long keel with more surface area? I can see in my mind that if the wave stalls the boat, the deep fin will no longer be providing lift, and might allow side slipping, avoiding being as caught in the wave motion. I just don't see it in the video (where the heck is the camera? It seems to remain vertical when the boat is horizontal. Gimbaled?) I don't think that rounding up is a desirable trait.

This thread has been making me think! Comparing a "flat" bottom modern shape to a "round/V bottom" shape, the flat will tend to orient to the face of the wave it is on, thus quicker to roll and come back.

But that means greater rotational acceleration. That also means greater acceleration of the passenger's bodies and "guts", which means it's more tiring and less pleasant. Further, greater acceleration means that the tall rigging is under greater stress. Greater work hardening and metal fatigue means the continuously greater acceleration increases the risk of rigging failure. This could be another reason older style boats were round/V shaped, they had natural wood spars and natural fiber rigging, both heavier and weaker than today.

Of course, this is a racing boat with a large crew. If cruising one wouldn't have lots of sail up, and would possibly be riding out the storm rather than trying to make the most headway possible, unless near a lee shore.


----------



## skygazer

BryceGTX said:


> Here is a picture what a boat with only hull righting moment does on a wave. And then how a rough water boat deals with waves.


Bryce, I didn't see your last post, I'd just woken up (5:30 AM) and somehow missed that there was another page. You'd already discussed much of what I was thinking about when I woke up. Appreciate your insights.


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## pvajko

Jeff, I'd like to thank you for your reply, this is exactly what I wished for, reasoning based on physics and not on authority. I really appreciate you took the time.



Jeff_H said:


> the statement seems to imply that a boat with a full keel will out perform a fin keel boat in heavy conditions, and while that may be true for some fin keels vs. full keels, it is not a universally accurate statement.


I'm not a native English speaker and sometimes have trouble to clearly state what I want to tell. All I tried to say is that a fin keel may generate a lot more lift in calm water but that advantage is lost in heavy seas, making the full keel safer (not faster). I hope this at least partly is correct.


----------



## PCP

BryceGTX said:


> You are correct that beam width is the best way to reduce heeling angle due to winds. Because it increases the hull righting moment. And I have said this earlier on this thread. However, excellent rough water boats are built with moderate beams with a more v-shaped hull design which actually reduces the effects of beam and such boats have significant mass in the keel.
> 
> ....
> 
> Here is a blurb *from a yacht design book from the 1800s that pretty much summarizes what we know even to this day*. Vessels with wide beams are most affected by wave motion. I think this is pretty much common knowledge.
> Bryce


It is really incredible that someone can believe that from 1800 to today nothing as been learned in what regards sailing boats , stability and particularly dynamic stability.

It is also hard to believe that someone that is obviously not a professional in sail design can believe that the best professional in that area, that design blue-water boats, don't know what they are doing and are designing today worst bluewater boats than what they were doing 30 years ago, not to mention 200 years ago

One of the most trusted bluewater boats are the Halberg-Rassy. Back in 1982 they did not use a full keel anymore and their 42ft had 3.78m beam.



















Today its new boat, the smaller 415 has 4.11m of beam and use a modern bulbed fin keel.










And this is not an isolated case but the norm in what refers to modern bluewater cruising boats. Sure, you can find narrower boats still made today but almost in all cases are old designs that are still produced today and that don't reflect the state of the Art neither the actual knowledge in hydrodynamics and boat design.

Happily there are very few like you, I mean that believe that know more than the best boat designers on the market, otherwise bluewater brands like Najad, Malo, HR, Moody or Oyster would still be making the same type of boats they have made 30 or 40 years ago

Regards

Paulo


----------



## PCP

skygazer said:


> Paulo, when I watch the video it appears there is a time edit between the first two waves, so there is no way to tell how long the interval is. Also, when I look at the clouds it looks like the boat is rounding up, I don't see the sideways motion.
> 
> Am I correct in thinking you mean that the narrow deep keel allows sideways slipping down the wave face, rather than tripping on a long keel with more surface area? .. I don't think that rounding up is a desirable trait.
> 
> This thread has been making me think! Comparing a "flat" bottom modern shape to a "round/V bottom" shape, the flat will tend to orient to the face of the wave it is on, thus quicker to roll and come back.
> 
> ....


It is not me that thinks that a a narrow deep foil keel allows a boat to move sideways or to rotate much easily than a full keel. I have learned from others including some very experience sailors and boat designers

They say that the boat was hit by a double breaker. This is the worst situation in what regards capsizing and one that leads many times to it.

Well, I can see clearly the boat moving, sideways and rotating. Any kinetic movement that uses the wave energy in any other away than on a rolling movement (induced by a big immersed area of a full keel) is welcomed and that includes rounding.

Regards

Paulo


----------



## pvajko

Jeff_H said:


> it is easy to see that a modern fin keel boat could easily develop much higher dampening moments and so have better dampening than a full keel boat, making Pvajko statement incorrect that _"The most important reason is that a full keel with its bigger surface area damps the rolling motion better." _


BTW Jeff, doesn't this imply that Paolo's argument with full keel boats "tripping over the keel" vs. fin keels moving easily sideways is incorrect?

It appears that the two statements contradict each other. I know you are talking about high dampening moments but doesn't that mean also higher resistance sideways?


----------



## GBurton

Bryce, thanks for your input on a very interesting subject. You too Pvajko.


----------



## skygazer

skygazer said:


> Am I correct in thinking you mean that the narrow deep keel allows sideways slipping down the wave face, rather than tripping on a long keel with more surface area? I can see in my mind that if the wave stalls the boat, the deep fin will no longer be providing lift, and might allow side slipping, avoiding being as caught in the wave motion.





PCP said:


> It is not me that thinks that a a narrow deep foil keel allows a boat to move sideways or to rotate much easily than a full keel. I have learned fro others including some very experience sailors and boat designers
> 
> Regards
> 
> Paulo


Paulo, I did not express myself clearly enough. Just be glad I'm not trying to express myself in Portuguese!

I was not questioning whether the idea of sideslip is true, I was trying to ask if it seemed I correctly understood the idea of sideslip. It seems quite possible that it could be a real benefit. By the way, I'm weak in higher mathematics, so the real life experience of others is exactly what I'm interested in.

I also enjoy your passion for the newer boats. I have zero experience with the modern designs, so I need to hear from people who do have experience.

I don't think anyone believes that they are designing worse boats today. They may however be designing with different goals, for a different market. Part of what's good about this discussion is it attempts to describe the attributes of the differing designs, it is then up to each of us to chose the attributes that best fit how we desire to sail.

While they did not have computers until recently, they did have many thousands of years of trial and error to refine their designs and gain understanding. The sea never changes, so many principals remain the same. Today we have newer materials, which allows further exploration. A big thank you to all racers and designers who push the limits. Now we have to struggle to understand what these new designs mean for us, and how each may find their own balance point.


----------



## mitiempo

When caught beam on to a large sea, a boat will try and slip sideways, downhill. The important part is can it do so easily or does the hull want to but the keel not want to.

As far as design changes over many decades, I think there are many more boats designed today that are designed to sail well in different conditions without being tweaked and distorted to meet a racing rule. There were certainly many distortions during the IOR rule years but remember many popular long keel cruisers were designed to a rule as well - a better rule but a rule that defined design type all the same. Most of the long keel designs that are popular now for offshore use were designed to race under the CCA rule - Albergs being a good example. Many of them were not intended by their designers to be sailed offshore either.


----------



## GBurton

PCP said:


> It is really incredible that someone can believe that from 1800 to today nothing as been learned in what regards sailing boats , stability and particularly dynamic stability.
> 
> It is also hard to believe that someone that is obviously not a professional in sail design can believe that the best professional in that area, that design blue-water boats, don't know what they are doing and are designing today worst bluewater boats than what they were doing 30 years ago, not to mention 200 years ago
> 
> One of the most trusted bluewater boats are the Halberg-Rassy. Back in 1982 they did not use a full keel anymore and their 42ft had 3.78m beam.
> 
> Today its new boat, the smaller 415 has 4.11m of beam and use a modern bulbed fin keel.
> 
> And this is not an isolated case but the norm in what refers to modern bluewater cruising boats. Sure, you can find narrower boats still made today but almost in all cases are old designs that are still produced today and that don't reflect the state of the Art neither the actual knowledge in hydrodynamics and boat design.
> 
> Happily there are very few like you, I mean that believe that know more than the best boat designers on the market, otherwise bluewater brands like Najad, Malo, HR, Moody or Oyster would still be making the same type of boats they have made 30 or 40 years ago
> 
> Regards
> 
> Paulo


Paulo, did you ever consider that MARKETING might have something to do with the new designs? 
Many people like you believe everything the manufacturers tell you that you should believe.


----------



## mitiempo

Once a couple bought an old mould from a company that failed. The design was a modified version of a 40+ year old rescue vessel. It became probably the most promoted sailboat in history, even hitting Time magazine. It was the Westsail 32.


----------



## GBurton

mitiempo said:


> Once a couple bought an old mould from a company that failed. The design was a modified version of a 40+ year old rescue vessel. It became probably the most promoted sailboat in history, even hitting Time magazine. It was the Westsail 32.


And very good boats they are. Thanks for the history lesson.


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## Chadfunk48

Burton, Why would the manufacturers (mostly) all agree that they would rather have people buying fin and other keel types as opposed to full keels? As long as they are promoting their boats and making money the full vs. fin wouldn't matter. I really don't think there is some marketing conspiracy to get people to buy a certain boat type. It's just the direction of the technology.


----------



## mitiempo

Boats are in most cases the products of racing rules. In the 50's and 60's the CCA rule helped create the type of long keel boats that were common. IOR favored a different type of boat entirely. Now there are more designs that are not fashioned after any rule and efficiency is the goal in many cases. Dragging a long keel around is not for the majority.

Burton

You are the one that suggested that marketing hype and believing manufacturers is not a good idea. I was just pointing out that the boat most promoted in memory is the Westsail 32, your favorite I believe.


----------



## GBurton

Chadfunk48 said:


> Burton, Why would the manufacturers (mostly) all agree that they would rather have people buying fin and other keel types as opposed to full keels? As long as they are promoting their boats and making money the full vs. fin wouldn't matter. I really don't think there is some marketing conspiracy to get people to buy a certain boat type. It's just the direction of the technology.


I think its probably more expensive to build a full keel boat than a fin/bulb. Also, I never said it was a marketing conspiracy but rather that some people (sometimes newbies) will believe what they are being told ..ie "fast is fun" or "full keel boats are slow and out of date" etc etc.

You get the idea.


----------



## GBurton

mitiempo said:


> Boats are in most cases the products of racing rules. In the 50's and 60's the CCA rule helped create the type of long keel boats that were common. IOR favored a different type of boat entirely. Now there are more designs that are not fashioned after any rule and efficiency is the goal in many cases. Dragging a long keel around is not for the majority.
> 
> Burton
> 
> You are the one that suggested that marketing hype and believing manufacturers is not a good idea. I was just pointing out that the boat most promoted in memory is the Westsail 32, your favorite I believe.


Are you saying that you agree with me?


----------



## skygazer

Re: Marketing - it is aimed at "most" people. Most people do not actually blue water sail, even though most may want a "blue" boat. Most people actually park in a marina, and coastal sail occasionally or rarely - preferably on a blue sky day. So, maneuverability is important, speed is important when out there, and beamy is important for amenities.

If it happens to require less material to build, that is fine also.


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## souljour2000

Having read all the various arguments in this most excellent thread thus far...I can only say that in my opinion neither the full-keel/ heavy-displacement folks nor the bulb-keel/light displacement/wide beam proponents have made a strong enough case to cast one's lot with one or the other...
There is evidence that seems to favor either one side or the other depending on the goals of the crew.... such as...take the long off-shore cruising couple or 3-4 four non-professional sailors in heavier full-keel boats who aren't in a race...but just trying to make a good offshore crossing or regional offshore cruise/jump... who may arrive a few days later...but perhaps had a less testosterone-pumping cruise... whereas the lighter wide beam race boat with gung-ho race crew and well-funded clients will likely complete the run days faster due to their boat speed and other amenities like satellite updates by a weather team onshore...and lots of race-driven "point A to point B" adrenaline/camaraderie....perhaps allowing them fly in the face of continuous rough-weather pounding like beam breaking waves hour after hour and so forth...

That said...I am looking forward to getting my (new) old '66 Columbia 40's rails wet this summer after she gets some work done on her and a clean bill of health...standing on her deck the other day in middle of a wide river when it was gusting to 20 mph...I was in disbelief at her solid, statuesque feel...though I had just moved up from a 8,400 lb to 18,200 lbs gross boat it was much more rock solid than I imagined and damn nice at anchor when it's blowin'...and I like to just be out on a boat at anchor sometimes...


----------



## Familycruisers

Full? Fin? 
What about Bilge!!!!!


----------



## souljour2000

I love the idea of bilge keelers though have never owned one...but damn...we don't wanna be threadkillers do we...? I've already put us in jeopardy with my non-committal statements in my post above without bringing the bilgers...
now what round was it...?


----------



## PCP

GBurton said:


> Paulo, did you ever consider that MARKETING might have something to do with the new designs?
> Many people like you believe everything the manufacturers tell you that you should believe.


I don't get it. It seems to me that Halberg Rassy would have an advantage in marketing different boats (old designed boats) if those boats were really better.

But if you have any doubts and think there is a conspiracy theory of all boat builders (including bluewater brands) regarding selling worse boats than what they used to do 30 years ago, just look at what are designing the most talented XXI century Naval architects and I don't mean the boats that are commissioned by the big brands but the ones that they make out of pleasure just to make a stand in what they believe or one offs for very good sailors and guys that can discuss with them the ideal cruiser for the kind of sail they want to do (and that includes many bluewater boats).

Look at all those boats and tell me if you see any heavy full keeler.

Regards

Paulo


----------



## PCP

mitiempo said:


> Boats are in most cases the products of racing rules. In the 50's and 60's the CCA rule helped create the type of long keel boats that were common. IOR favored a different type of boat entirely. Now there are more designs that are not fashioned after any rule and efficiency is the goal in many cases. Dragging a long keel around is not for the majority.
> 
> ...


Yes I agree but there is something new in what regards that: Actually the broad transoms, beamy boats and fin torpedo keels are very penalized in handicap racing under any rule and you can see that many modern cruising boats have those characteristics.

They get them from Open boats where more importance is given to absolute performance instead of performance under a given set of rules.

Even between the racers for the first time you can see guys given more importance in going fast and having fun then to win races with slow boats with big handicaps.

When MAX yachts included the racing sailor opinions as a mean to got information to design its late 11ft he found out that what sailors wanted was the fastest boat they could get independently of being capable of winning races on handicap or not.

This is something new and has to do with the predominance of Open racing boats in the racing panorama in what concerns media attention and even sailor's attention.

Regards

Paulo


----------



## GBurton

PCP said:


> I don't get it. It seems to me that Halberg Rassy would have an advantage in marketing different boats (old designed boats) if those boats were really better.
> 
> But if you have any doubts and think there is a conspiracy theory of all boat builders (including bluewater brands) regarding selling worse boats than what they used to do 30 years ago, just look at what are designing the most talented XXI century Naval architects and I don't mean the boats that are commissioned by the big brands but the ones that they make out of pleasure just to make a stand in what they believe or one offs for very good sailors and guys that can discuss with them the ideal cruiser for the kind of sail they want to do (and that includes many bluewater boats).
> 
> Look at all those boats and tell me if you see any heavy full keeler.
> 
> Regards
> 
> Paulo


whooosh


----------



## blt2ski

At the end of the day, does not matter if it is a fin or full keel, round, flat or V bottom. Does it have the ability to carry the stores etc that a person(s) is going to put in it, then not slow down tremendously, still go to weather, down wind, handle large waves/wind, etc 

If it will not do the above in the terms/specs "YOU" have for said boat, then it is more than likely under specked, potentially over, but more than likely, under specked for the use that the end user has in mind!

marty


----------



## Oregonian

mitiempo: “isn’t that a fair comparison” to compare boats by their displacement. Yes, I agree it is fair. The Westsail 32 vs. the Beneteau 42; and the Alajuela 38 vs. the Bavaria 50.
Skygazer: “Marketing is aimed at “Most” People”. Few things in boating are more true. Thanks for the comments.
Benjmin: “This is great” . Yes it is, and long overdue. Your boat looks great too. Thanks for the pics.
Paulo: Thanks for the great video and your continued input. My wife and I have decided NOT to buy a Volvo 70 as our next cruising boat.
BryceGTX: The thumbnails you posted were very helpful and saves a lot of words. All of your input has been welcomed (by some).

Yes, a heavy, full keel cruiser will cost more to produce. Yes, most of the light weight modern designs can sail faster in smooth water when empty. To disregard the valuable benefits of the heavier displacement and/or the full keel is not a step forward toward a better long range voyaging sailboat. IN THE SMALLER SIZES, both attributes can enhance over-all performance. My experience is not as a naval architect, nor as a marketer. It is as a sailor who lives with their results. 
The flatter the bottom the quicker the “snap”. If any of the critics say otherwise they are blowing smoke and indicating a lack of experience. The lighter the boat the more it will pound. If any of the critics say otherwise . . . . . In the smaller sizes, this cannot be taken lightly. The modern, light weight sailboat when heavily loaded will lose significant performance, usually falling below the performance of the boat that was designed heavier in the first place. If any of the critics say otherwise they are blowing smoke and indicating a lack of experience. 
I repeat all of this for a reason. The newbies. There are many reasons why most boats are fin keeled and light weight. There are also justifiable reasons why heavier displacement and, perhaps, a full keel are very viable options.
As I read of the many theoretic advantages of the fin keel by so many critics of the full keel, ie the “Tip vortices drag”, the” reduced wetted surface”, the “lift”, etc, etc, I counter that much of the hype falls into the category of “statistically insignificant”. That is my opinion, as it applies to the smaller sizes of long distance voyaging sailboats. As I have of a history of “Deleted” posts, I must not say any more. 
Thankyou

Blt2ski: Thanks for that input. I see you are a wise man.


----------



## skygazer

Oregonian said:


> As I have of a history of "Deleted" posts, I must not say any more.


I hope that this is a case of normal screw ups with site traffic. I think you add a valuable viewpoint, and I definitely appreciate it.

How interesting is a one sided discussion anyway?


----------



## PCP

Oregonian said:


> mitiempo: ....
> Paulo: Thanks for the great video and your continued input. My wife and I have decided NOT to buy a Volvo 70 as our next cruising boat.
> ....


If you understood that I was purposing to someone a VOR 70 as cruising boat it is probably because my English is a lot worse than what I thought or you did not understood nothing that I have said.

Basically what I have said is that if you have the money to buy the better boats money can buy, go to one of the top NA that design the VOR 70, the Open 60 and the 40 class boats, and work with them with your criteria for a cruising boat. If you don't have all that money look at the boats they have designed recentely and are produced by the market builders: You have them for all kind of cruising, from coastal to bluewater, from deck saloons to fast performance cruisers, from centerboarders, twin keels, fin keels or foil keel with a torpedo.

In any case you would not end up with a heavy full keeler.

If You don't have the money for that, you can buy one of the boats designed by those guys 10 years ago. It will not represent the actual state of the art but it will not be very far away.

If you don't have money for that you can buy an old boat. If it is really old designed it will be a full keel boat but most of the cruising boats with 30 years, even bluewatet boats, are already not full keeled boats, but a kind of a compromise between a fin and a full keel.

Any boat is better than no boat and once you have one, well, that's the one that matters to you and it will be certainly the one you love the most

Regards

Paulo


----------



## GBurton

PCP said:


> If you understood that I was purposing to someone a VOR 70 as cruising boat it is probably because my English is a lot worse than what I thought or you did not understood nothing that I have said.
> 
> Basically what I have said is that *if you have the money to buy the better boats money can buy*, go to one of the top NA that design the VOR 70, the Open 60 and the 40 class boats, and work with them with your criteria for a cruising boat. If you don't have all that money look at the boats they have designed recentely and are produced by the market builders: You have them for all kind of cruising, from coastal to bluewater, from deck saloons to fast performance cruisers, from centerboarders, twin keels, fin keels or foil keel with a torpedo.
> 
> In any case you would not end up with a heavy full keeler.
> 
> If You don't have the money for that, you can buy one of the boats designed by those guys 10 years ago. It will not represent the actual state of the art but it will not be very far away.
> 
> If you don't have money for that you can buy an old boat. If it is really old designed it will be a full keel boat but most of the cruising boats with 30 years, even bluewatet boats, are already not full keeled boats, but a kind of a compromise between a fin and a full keel.
> 
> Any boat is better than no boat and once you have one, well, that's the one that matters to you and it will be certainly the one you love the most
> 
> Regards
> 
> Paulo


I do not presume to speak for Oregonian, but once again you seemingly unable to grasp what some of us have been saying.

Some of us do not want a flat bottomed, twitchy, "state of the art" boat.

What is "better"?

Are you telling me what I should like?


----------



## PCP

GBurton said:


> I do not presume to speak for Oregonian, but once again you seemingly unable to grasp what some of us have been saying.
> 
> Some of us do not want a flat bottomed, twitchy, "state of the art" boat.
> 
> What is "better"?
> 
> Are you telling me what I should like?


Surely there is something with my English I have said:

"Basically what I have said is that if you have the money to buy the better boats money can buy, go to one of the top NA that design the VOR 70, the Open 60 and the 40 class boats, and work with them with *your criteria for a cruising boat*."

For instance go near Bruce Farr and tell him that you want a boat with a soft motion, an easy going boat upwind, a bluewater boat and let him decide how to manage those characteristic without a big loss of speed or interior space.

I am assuming he knows a lo more than you and has the knowledge and is able to do a state of the art boat accordingly with your criteria.

* A state of the art boat means not a racer but the best available solution, with today's technology and hydrodynamics knowledge, for a boat with the characteristics you want.*

What I am saying is that is not going to be a full keel boat just because he knows that he doesn't need a full keel boat to obtain what you want and a full keel will make the boat unnecessarily slow.

Of course I am assuming that one of your criteria for a cruising boat is not a purposely slow boat.

Regards

Paulo


----------



## GBurton

PCP said:


> Surely there is something with my English I have said:
> 
> "Basically what I have said is that if you have the money to buy the better boats money can buy, go to one of the top NA that design the VOR 70, the Open 60 and the 40 class boats, and work with them with *your criteria for a cruising boat*."
> 
> For instance go near Bruce Farr and tell him that you want a boat with a soft motion, an easy going boat upwind, a bluewater boat and let him decide how to manage those characteristic without a big loss of speed or interior space.
> 
> I am assuming he knows a lo more than you and has the knowledge and is able to do a state of the art boat accordingly with your criteria.
> 
> * A state of the art boat means not a racer but the best available solution, with today's technology and hydrodynamics knowledge, for a boat with the characteristics you want.*
> 
> What I am saying is that is not going to be a full keel boat just because he knows that he doesn't need a full keel boat to obtain what you want and a full keel will make the boat unnecessarily slow.
> 
> Of course I am assuming that one of your criteria for a cruising boat is not a purposely slow boat.
> 
> Regards
> 
> Paulo


Those are a lot of assumptions.

I already have the boat with the characteristics that I want. For probably less than the cost of Bruce Farrs consulting fee. Not to mention the cost to build the boat.

His interpretation of what makes a good cruising boat may be different than mine.

Its not hard to understand.


----------



## souljour2000

Yeah but is the state of the art really any better than it was 30 years ago?....aside from weather input is the question...I think ....Perhaps..a big reason these racers and others go out in these lighter beamy boats since what... the early 80's... is mostly due to satellites stuck in the sky in the mid 70's that could finally show a storm and transmit data so that these lighter faster beamy boats can get to the weak corner of the storm...There..I said it...I think that it's the weather and other tech input more than anything since the 70's that gives "state of the art" race teams and their weather teams on dirt a decent chance to outrun bad weather that the race designers felt safe enuff to come up with these type boats and the commericial hunterbenelina designers followed...I think that's fine....no ones said it till now...but playing devil's advocate.......I think that that's their ace in the hole...their speed...but meanwhile much of the time...,they are pounding and difficult on race crews if raced...or plodding and weather-windowed if cruised and overburdened with gear...which may well cancel their speed vs. the weather edge...just some thoughts...bet that rumpled some feathers...thats one of my theories for awhile and I'm throwing it out there because I am not seeing any other advantage to new designs aside from materials and weather/nav tech and I've thought on it for awhile...the new boats are merely taking advantage of the state of the art of meteorology , not yacht design...though some progress has been made it's been more materials/tech than some new over-arching philosophy of beamy and light is better...Who other than the hardcore big-ballers would really go to sea in those type boats with say 1960's weather forecasting...truly brave mariners...with iron stomachs...Polynesians and others did it..but that was along time ago...


----------



## PCP

souljour2000 said:


> Yeah but is the state of the art really any better than it was 30 years ago?..


Of course, like in cars, airplanes and everything else. New materials, new knowledge is continually integrated in boat, car, airplane or motorcycle design.



GBurton said:


> Those are a lot of assumptions.
> 
> I already have the boat with the characteristics that I want. For probably less than the cost of Bruce Farrs consulting fee. Not to mention the cost to build the boat.
> 
> His interpretation of what makes a good cruising boat may be different than mine.
> 
> Its not hard to understand.


A Naval Architect, or an any Architect for that matter, does not design accordingly with his personal point of view.

Farr would not have made a cruising boat to you according to his personal view or criteria _*but according with your view*_.

The Criteria is yours he would just find the better materials and the better hull and keel design to accomplish what you want.

As he know a lot more than you he would be able to design a boat that you would find perfect but a boat that would incorporate all the hydrodynamics knowledge and advantages of modern materials, he would do you a state of the art boat in what concerns the satisfaction of your needs, including sea motion but would make you a much better and faster boat that any old boat, even if one of your design Criteria would be that the boat looked like a classic boat.

If he could not do that he would not be a good NA and Bruce Farr is one of the best.

Just to explain myself better regarding what Architects do, a little story:

Some years ago a rich German come to me, recommended by another client and asked me if I could do him a "Romantic house". I said sure and then passed some weeks understanding what was for him and his wife a "Romantic House". When I understood what was "Romantic" for them I designed a house that they both loved, a "Romantic house", but a modern house in what regards building materials, construction functionality and easy of living.

He thinks that house is a perfect house and he even think that If I could (it is a huge house) I would live in one like that. Of course, he could not be more wrong

Regards

Paulo


----------



## GBurton

PCP said:


> Of course, like in cars, airplanes and everything else. New materials, new knowledge is continually integrated in boat, car, airplane or motorcycle design.
> 
> A Naval Architect, or an any Architect for that matter, does not design accordingly with his personal point of view.
> 
> Farr would not have made a cruising boat to you according to his personal view or criteria _*but according with your view*_.
> 
> The Criteria is yours he would just find the better materials and the better hull and keel design to accomplish what you want.
> 
> As he know a lot more than you he would be able to design a boat that you would find perfect but a boat that would incorporate all the hydrodynamics knowledge and advantages of modern materials, he would do you a state of the art boat in what concerns the satisfaction of your needs, including sea motion but would make you a much better and faster boat that any old boat, even if one of your design Criteria would be that the boat looked like a classic boat.
> 
> If he could not do that he would not be a good NA and Bruce Farr is one of the best.
> 
> Just to explain myself better regarding what Architects do, a little story:
> 
> Some years ago a rich German come to me, recommended by another client and asked me if I could do him a "Romantic house". I said sure and then passed some weeks understanding what was for him and his wife a "Romantic House". When I understood what was "Romantic" for them I designed a house that they both loved, a "Romantic house", but a modern house in what regards building materials, construction functionality and easy of living.
> 
> He thinks that house is a perfect house and he even think that If I could (it is a huge house) I would live in one like that. Of course, he could not be more wrong
> 
> Regards
> 
> Paulo


You are right Paulo, a skilled NA should be able to design a small cruising boat with the characteristics that I'm looking for.

That begs the question, where are these boats? Has the public been duped into thinking that they need an "interesting boat"?


----------



## Faster

This is clearly an unwinnable argument, and I think the two sides need to agree to disagree and move on.

Statistically I think the vast majority of coastal cruisers appreciate a more nimble, maneuverable design than your typical full keeler. But it's great that those who prefer that style still have boats around that will fulfill their needs. And for ocean crossings, while the relative merits are obviously still debatable the main shortcomings of the full keel are far less relevant.



> That begs the question, where are these boats?


The very fact that very few builders are still producing such boats, however, pretty much answers your question, GB. Duped or enlightened?? To each his/her own.


----------



## blt2ski

As I attempted to say, maybe some agreed, one can get any style of boat designed, be it a fin or full keel to do what one wants. BUT, as pointed out, one needs to look at disp to disp. SO I looked up to known ocean goers that would be somewhat equal to my Jeanneau arcadia that is listed at 6200 lbs. A Dana 24 7200lbs and a Flicka at 5000-5500.

The SA/Disp of the flicka at sailboatdata.com was 12-1, with what I could tell was no ability to increase Upwind SA via a 155 or equal. The dana was a bit better at 15.x -1, potential to increase, but not easy. My Arcadia, base is 18-1, with a 155 I am at 25-1. 

Bal disp, the flicka and mine are around 32%, the dana 40%. BUT, who is to say at my 5.5' draft that my 32% is worst or better or on par with the dana, probably better than the flicka. With out cranking some numbers......swag on my part.

Reality is, any of these with much more than about 2000 lbs of gear people etc is going to be hard on it for a longer trip! At least, if one hits the proverbial doldrums, my boat can have more power per lb/ton of wt than either of the others, along with a mast that is 40' off the water, vs low 30' range for the dana, and maybe 30' for the flicka. So if any higher than the waterline winds are there, I'm may still moving. 

My WL is longer than either boat in length. Being as WL will help contribute some lessening of motion per say in some conditions, other worst, ALL boats have a wave length if one will that will be on par with another of equal lbs if that is what one is using to compare. Capsize ratios seem to go up higher the longer the boat vs shorter boats of equal disp etc.

With PHRF ratings of about 40 secs slower for the dana, and just over 2 min a mile for the flicka than my boat. A 1000 mile passage will take approx 11 hrs longer with the dana, and 33 hrs longer with the flicka. assuming I did the math correct. I would bet it could be longer yet! being as PHRF secs a mile difference do not always add up correct at the end of the day. Using 80% of hull speed to go 1000 miles, the flicka is 222 hrs, dana 204, arcadia 186. More than PHRF differences. Potentially up to 1 and 2 days more for those boats. 

If one could hit some downwind work, with my being able to surf, and have over 900# of SA with a spin, the other two do not list, It could be upwards of 2 and 4 days quicker for my boat to do the 1000 miles. 80% speed is 4.5, 4.95 and 5.36 knots for these boats.

At the end of the day tho, we need a boat that will work for us as individuals. how we sail, where we sail etc. 

Designers current and last boats that I know of. Farr used to sail a Laser 28 and F1020, both of his designs. Not sure what he sails now. Daniel Andrieu(sp) has a Jeanneau Sunfast 3200 for him and his family. Finot, has a similar style of boat to the SF3200, but a higher tech material for lack of better term for his personal and his design built by that company. Tony Castro has a 40'ish foot boat that is on par with an Alerion or Morris M series, but it has more of an open ocean interior, but older style with a very modern under body fin keel! the latter three sail there boats from the UK to France etc. Certainly some open water than can get interesting to say the least.

Bob Perry, while he does not sail one of his own boats, it is from what I can tell, on par with my boat, but a bit shorter, also a european built IIRC. His cruisers are not generally speaking full keels, more of a moderate fin, so they can be quick!

Most of us want something that is fun to sail, maneuverable, safe, has storage for our personal needs, and a design that works for where we sail! For some, maybe a full keel, other a bildge, some a centerboard ala Finot's boat, others a fin keel! some twin rudders, some single.......in the end, does the boat make your heart spin! as a good women, or man if that is your choice will. There is no right or wrong to keel type per say. Only what you think will work best for you. I'll take a fin, CB, moderate fin to a full keel in that order!

Marty


----------



## Familycruisers

blt2ski said:


> Most of us want something that is fun to sail, maneuverable, safe, has storage for our personal needs, and a design that works for where we sail! For some, maybe a full keel, other a bildge, some a centerboard ala Finot's boat, others a fin keel! some twin rudders, some single.......in the end, does the boat make your heart spin! as a good women, or man if that is your choice will. There is no right or wrong to keel type per say. Only what you think will work best for you. I'll take a fin, CB, moderate fin to a full keel in that order!
> 
> Marty


All the rest...IDK
but this sums it up for me, even if you did mispell bildge, (we're such a red headed step child) But hey, 
I wanted a camper on the water and thats what I got...


----------



## skygazer

blt2ski, nice post, thank you!


----------



## skygazer

Familycruisers said:


> Full? Fin?
> What about Bilge!!!!!


I don't know if this should be another thread, but bilge keels look very interesting. Which ever way the boat heels, one (somewhat pathetic) keel is almost straight up and down, which to my mind means they can be as effective as a deeper keel running at an angle. And the other one, well, is vertical stability desirable or undesirable in a seaway?

Do they make them with aerodynamic keels, or just flat plates? There is one (British made) just down the road from me, looks very cool. I haven't examined it, but I'd love to. Could be a bugger to get off a sandbar.


----------



## halyardz

*Re: Full or fin keel? Depends*

I tend to agree with jackdale the full keel is more sea-kindly but doesn't point as well. If you are heading to Bahamas or other shallow waters, a full keel might be a better choice. Years ago, planning Bahamas/FLA cruising, we elected to go with a Tartan 33 (S&S designed classic plastic) with a Scheel keel. Fully loaded she carries a 4'9-10" draft. You don't find Scheel's on too many classic boats but they are solid and point a bit better, while offering a shallower draft. Not too sure why they weren't more popular.


----------



## mitiempo

Skygazer

Yes they do.
RM YACHTS | Accueil


----------



## skygazer

mitiempo said:


> Skygazer
> 
> Yes they do.
> RM YACHTS | Accueil


WOW!!! Really nice looking boat. It LOOKS fast!

Next question, did they make any like that 30 years ago so I can afford one?


----------



## mitiempo

Don't think so.


----------



## blt2ski

SKygazer,

Sorry, but unless something different has happended back then, most were not very fast back in the day. The newer ones by RM seem to be adding some of todays design elements into a setup that frankly, could be quick, etc. ALong with make for a boat that will cruise, race if need be, carry some weight, be fun to sail etc.

Still, not "my" style of boat.....but, if it is yours, frankly "GO FOR IT!" I'm not going to say a given boat is right or wrong. I do have a what I prefer if I bought a boat today, not sure if it would be the Jeanneau SF3200, or the Elan 310/350. Those are close to being affordable, and a design that would work for how "I" sail etc. The E350 would be more to my wifes liking, better yet one of the 40-45' DS style boats........yucko! but if the wife is not happy.....neither is I!LOLOL

Marty


----------



## GBurton

skygazer said:


> Paulo, when I watch the video it appears there is a time edit between the first two waves, so there is no way to tell how long the interval is. Also, when I look at the clouds it looks like the boat is rounding up, I don't see the sideways motion.
> 
> Am I correct in thinking you mean that the narrow deep keel allows sideways slipping down the wave face, rather than tripping on a long keel with more surface area? I can see in my mind that if the wave stalls the boat, the deep fin will no longer be providing lift, and might allow side slipping, avoiding being as caught in the wave motion. I just don't see it in the video (where the heck is the camera? It seems to remain vertical when the boat is horizontal. Gimbaled?) I don't think that rounding up is a desirable trait.
> 
> This thread has been making me think! Comparing a "flat" bottom modern shape to a "round/V bottom" shape, the flat will tend to orient to the face of the wave it is on, thus quicker to roll and come back.
> 
> But that means greater rotational acceleration. That also means greater acceleration of the passenger's bodies and "guts", which means it's more tiring and less pleasant. Further, greater acceleration means that the tall rigging is under greater stress. Greater work hardening and metal fatigue means the continuously greater acceleration increases the risk of rigging failure. This could be another reason older style boats were round/V shaped, they had natural wood spars and natural fiber rigging, both heavier and weaker than today.
> 
> Of course, this is a racing boat with a large crew. If cruising one wouldn't have lots of sail up, and would possibly be riding out the storm rather than trying to make the most headway possible, unless near a lee shore.


You are correct it was two waves separated by quite a bit of time... in the second wave footage on of the crewmen is missing. Paulo lost a little in the translation there.

The speed that boat exhibits is a beautiful thing but the trade off in comfort is brutal. (Stating the obvious) Also, if the boat had been inverted would it have righted itself?


----------



## PCP

GBurton said:


> You are correct it was two waves separated by quite a bit of time... in the second wave footage on of the crewmen is missing. Paulo lost a little in the translation there.


Well, we don't know the time that separated the two waves but for what they say it did not seem that much:

*"Telefónica survive monster wave double hit*:

...The amazing footage shot from the stern camera shows the entire on-deck crew -- including the helmsman -- *twice knocked off their feet by the force of the up- to-10-metre waves."*



GBurton said:


> ...Also, if the boat had been inverted would it have righted itself?


Contrary of practically all sailboats, full keelers or not, this boats (like the Open 60's) can right itself up after been inverted in flat water by their own means. When inverted cruising sailboats need the help of waves to return from an inverted position. On flat water they will stay inverted.

Regards

Paulo


----------



## blt2ski

Also, IIRC, these V70 and open 60 boats to get certified, HAVE TO be inverted with rigs, put in the water, and right themselves with in "30 secs" to be able to race these races. Not sure if it is 30 secs, 45, 10 or ______! but there is a literal test to verify it can right itself with in the allotted time period. Or it is a no go.

I am sure, not only is the wt on the keel, type etc a factor, but deck design too would also come into play etc too.

Marty


----------



## GBurton

blt2ski said:


> Also, IIRC, these V70 and open 60 boats to get certified, HAVE TO be inverted with rigs, put in the water, and right themselves with in "30 secs" to be able to race these races. Not sure if it is 30 secs, 45, 10 or ______! but there is a literal test to verify it can right itself with in the allotted time period. Or it is a no go.
> 
> I am sure, not only is the wt on the keel, type etc a factor, but deck design too would also come into play etc too.
> 
> Marty


I remember seeing a video of that. The boat was inverted without its rig (by using a crane) and then the crewman inside cranked the keel over to the one side by means of a hand hydraulic pump. Seems a little _extreme_
Would the mast help or hinder the roll-up?


----------



## GBurton

PCP said:


> Well, we don't know the time that separated the two waves but for what they say it did not seem that much:
> 
> *"Telefónica survive monster wave double hit*:
> 
> ...The amazing footage shot from the stern camera shows the entire on-deck crew -- including the helmsman -- *twice knocked off their feet by the force of the up- to-10-metre waves."*
> 
> Contrary of practically all sailboats, full keelers or not, this boats (like the Open 60's) can right itself up after been inverted in flat water by their own means. When inverted cruising sailboats need the help of waves to return from an inverted position. On flat water they will stay inverted.
> 
> Regards
> 
> Paulo


Paulo, it just means two waves hit the boat.. they could have been 2 hours apart. From the video it is obvious that they were not consecutive (the crewman on the stbd side is not present in the footage of the second wave.)

I also beg to differ on the cruising sailboat staying inverted in flat water - it depends on what cruising sailboat you are talking about. I'm pretty sure my Westsail 32 would roll back up in flat water without - assistance.
Some of the_ interesting cruising boats_ may not.


----------



## b40Ibis

Example of well blended design compromises- keel/centerboard design of the bermuda 40- ... but she don't back, strait. She spins as she backs. This is predicable and usually manageable except in strond tide and /or wind.


----------



## PCP

Mitiempo is right. Used RM boats are very hard to get. There are a lot of sailors that would like to have one and that makes the prices of the used boats high:

FORA MARINE RM 1050 - Voilier FORA MARINE RM 1050 d'occasion - Page 1

There are however a twin keel sailboat that is possible that you would like even better that the RM. It is a more classical boat and also a favorite among French sailors. It is a seaworthy and the boat is made almost without alterations for a lot of years. I am talking about the Biloup.

They are making now a new 365 that I will post on "interesting sailboats" soon but they have a 36ft and a 30ft for a long time.

Wrighton Yachts | Bi-loup 365

They are not cheap because, like the RM, there are more sailors wanting them than the boats they have available but I guess they can be older and therefore not as expensive. For instance this one for 65 000€ that sailed far for 8 years.

Bateaux autour du monde - Sail The World - L'Univers de la grande croisière en voilier - STW

site de Mareja

Or these, even less expensive.

biloup France - Bateaux France

Regarding speed and twin keels look at this Bongo. The first movie is from a Transat race with a duo crew. They have done well.


----------



## RickWestlake

Yahhh ... but Hinckley makes a _gorgeous_ boat. And you didn't buy Ibis to back her up, now, did you? 

2011 was my first year with a proper keelboat, a Bristol 29.9 - and as much as I learned about prop-walk over a summer of backing her into my slip, I know full well that I've only scratched the surface. (Well, actually, scratched the topsides. More than once.) But I was glad to find a boat like the Bristol, with her long, shallow-draft keel and her big solid skeg-protected rudder. After two seasons with Bossa Nova, my previous MacGregor 26 (a tender centerboard boat that gives up a lot of leeway), I wanted to go to the other extreme; and the 29.9 looked right, felt right, sailed right, and she's still right for my tastes and the next couple of years' worth of my goals.

Maybe some day I'll be sailor enough for a lovely yawl like the Bermuda 40 ...


----------



## mitiempo

I don't think anyone has mentioned the type of boat that is very popular in France, often aluminum and with a centerboard. The name most common over here is Alubat's Ovni. Not a light fast boat but a very comfortable cruiser with a good performance and a shallow draft that opens up some interesting options.


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## blt2ski

GBurton said:


> I remember seeing a video of that. The boat was inverted without its rig (by using a crane) and then the crewman inside cranked the keel over to the one side by means of a hand hydraulic pump. Seems a little _extreme_
> Would the mast help or hinder the roll-up?


I'll admit, I do not know if the rig would or would not help/hinder the roll-up. BUT, they do have to roll back up granted with the help of the canting keel to one side, but roll up they must with in this test. Not sure one could invert one with the rig on it. So from that point of view, the inverted test that they do, will have to make do until someone can figure out how to test with the rig.

They do some different things in Europe to certify boats built over their, and here to meed certain specs. One of them is literally inverting a boat and seeing if it will roll back up. OR< the architect has to show using a know formula that the boat will roll back up right. Not sure your W32 or for that matter, my 85 Jeanneau would or would not pass the test. They may roll back up, but with in the allotted time........

marty


----------



## mitiempo

Here's one of the Open 60 capsize tests.
Open 60 Capsize tests Video by Myles - Myspace Video


----------



## pvajko

Paolo,

I'm still struggling with these two statements, one from you:



PCP said:


> It is not me that thinks that a a narrow deep foil keel allows a boat to move sideways or to rotate much easily than a full keel. I have learned from others including some very experience sailors and boat designers


And this one from Jeff:



Jeff_H said:


> it is easy to see that a modern fin keel boat could easily develop much higher dampening moments and so have better dampening than a full keel boat


Now, if a fin keel allows the boat to "rotate much easily" as you say, then how can it have a "much higher dampening moment" at the same time?
I feel that both can not be true. Of course, I may be wrong and these are not contradicting statements but I fail to see why, maybe you can tell.

Peter


----------



## PCP

pvajko said:


> Paolo,
> 
> I'm still struggling with these two statements, one from you:..
> 
> Now, if a fin keel allows the boat to "rotate much easily" as you say, then how can it have a "much higher dampening moment" at the same time?..
> 
> Peter


Peter you shoud be very carefull when quaoting somebody. I believe you did not have intention but I never said that *"a fin keel allows the boat to "rotate much easily"*

I have said:



PCP said:


> ...
> 
> Regarding inertia and roll moment of inertia, let's consider two boats with the same positive area under the RM curve, and *therefore needing the same energy to be capsized*. One is a long keeler, small draft, narrow heavy weight boat the other one is a beamy light boat with a big draft and all the ballast on a bulb at the end of a fin keel.
> 
> As I had said before the dynamic behavior of these boats when hit by a breaking wave will be very different in what regards the capacity to dissipate the wave energy moving sideways, but let's consider that the full keeler would not trip in its keel, that the extra surface would not have a damping effect on the rotational movement and that *the low mass and small under water surface would not permit the lighter boat to move much more easily sideways.
> *
> 
> Let's consider that the same amount of energy of the wave that hits the boats results in a rotational movement for both boats. *Both boats require the same energy to be capsized so in what regards the results (capsizing or not) the effect would be the same but the kind of movement due to inertia would be very different.*
> 
> *The heavier boat would start to roll much more slowly but because it has much more inertia once started the rolling movement it would be much harder to stop it. On the lighter boat the roll movement will be faster but will be also stopped faster because the inertia is much smaller. Both boats will roll to the same point but the duration of the roll movement (to capsize at 90º and back to its feet) will be much longer on the heavier boat.*
> 
> We could say that the slower movement is a more comfortable one but the fact is that in what regards seaworthiness the heavier boat will be much more time deeply heeled, exposing its side much longer to another breaking wave that will catch him with little stability left and therefore will have potentiated effects, resulting probably in a capsize.
> 
> ...
> Paulo


As you can see I have said that the energy required is the same and therefore the Fin keel boat will not *"rotate much easily"*. It will rotate faster, it will stop the rolling movement faster and will return to its feet faster, but both boats will heel to precisely the same angle of heel.

Let me point out that this has not to do with the fin or the full keel but with the types of boats that are associated with. I have said regarding the boats:

*"One is a long keeler, small draft, narrow heavy weight boat the other one is a beamy light boat with a big draft and all the ballast on a bulb at the end of a fin keel".*

Regards

Paulo


----------



## PCP

mitiempo said:


> I don't think anyone has mentioned the type of boat that is very popular in France, often aluminum and with a centerboard. The name most common over here is Alubat's Ovni. Not a light fast boat but a very comfortable cruiser with a good performance and a shallow draft that opens up some interesting options.


That is the kind of boat most French would consider a voyage and a bluewater boat. They have a bit more ballast than fin keel boats but even so they are not very heavy, thanks to its aluminum construction. For instance, an OVNI 395 weights 8800kg and a Bavaria 40 weights 8680kg.

Regarding speed they do not point as well as a good fin boat but I guess the difference will not be much if any compared with a full keel boat. They sail fast downwind with the centerboard up, and I mean really fast (can reach double digit figures) and as most ocean voyages are made following the trade winds, these boats are relativelly fast voyage boats.

Have a look at the OVNI performance (several boats) on the last ARC and you will be surprised.

Regards

Paulo


----------



## PCP

GBurton said:


> ...
> Would the mast help or hinder the roll-up?


In a static situation without waves I don't know but recent tank testing showed that in a dynamic situation with waves the mast will help the boat to right itself up faster. Yes I know, it looks odd, but I read the paper and against facts there are no arguments...just the need to understand why

Regards

Paulo


----------



## pvajko

PCP said:


> Peter you shoud be very carefull when quaoting somebody. I believe you did not have intention but I never said that *"a fin keel allows the boat to "rotate much easily"*


Well, Paolo, I (the forum engine) quoted that from your own post, click on the little arrow in the quote box and you'll see.

But we seem to be talking about two different things. I'm talking about your tripping over the keel scenario where you seemed to say that the beamy, fin keel boat will slip sideways rather than roll over. That is, I think in contradiction with what Jeff said (today's fin keel boats have better dampening than full keels) because if a fin keel as at least as good dampening as a full keel, I can not see why would it slip more easily sideways, but again, I may be wrong here.


----------



## GBurton

In effect Paulo is saying "the wider boat with fin keel will snap faster than the full keel boat, but both will heel to the same angle"
So what happens when that heel angle is reached? Does the fin keel boat just sit there, frozen in time?

I'm confused as well Peter. I would also have thought that "rotate much easier" would mean "snap faster" as well.

None of this addresses your question about damping. Perhaps he didn't understand what you were asking.


----------



## skygazer

PCP said:


> In a static situation without waves I don't know but recent tank testing showed that in a dynamic situation with waves the mast will help the boat to right itself up faster. Yes I know, it looks odd, but I read the paper and against facts there are no arguments...just the need to understand why
> 
> Regards
> 
> Paulo


Faster righting from inverted (turtle) position with rigging and mast, than without, that is not very intuitive.

In science I learned that one can usually devise an experiment to get the results desired.

Here is a possibility. A beamy shallow hull, compared to a deep V hull, is very stable upside down, and will resist righting. Thus the fascinating tilting keel in the video in this thread, to change the dynamics of the beamy hull.

A mast will hang down deep, well below the wave action, in deep still water. So if beam on, the waves could carry the hull along while the mast stays behind, thus in effect starting the roll towards righting.

But generally a mast and rigging stabilize the rolling of the hull, so generally it would greatly slow the rolling back from an inverted position. If the boat was not beam on to the waves, I would think it would have to wait until (and if) wave action slewed it around to beam on. A rogue wave may not have another behind it strong enough to push the hull beyond the mast. If wind capsized the boat, the waves might not be strong enough, and lacking the leverage of the mast, the wind will slide over the hull.

As an extreme example, a flat (beamy) board will resist rolling, but a round log will roll very easily. When I fell a tree it tips over very slowly, like the mast and rigging. Once on the ground, I can roll the log easily, like a dismasted boat.

This has remained an incredibly interesting thread, thank you to all who provide their insights, thoughts, and experiences.


----------



## PCP

GBurton said:


> In effect Paulo is saying "the wider boat with fin keel will snap faster than the full keel boat, but both will heel to the same angle"
> So what happens when that heel angle is reached? Does the fin keel boat just sit there, frozen in time?
> ....


Snap is a bad word to describe the movement but since you are using it:

*So what happens when that heel angle is reached? Does the fin keel boat just sit there, frozen in time?*

No, the boat will snap back almost as fast as it snap before on the opposite direction. When the light boat is already "snapped" back, the heavier boat is probably still rolling down slowly or perhaps it is starting slowly to come back to its feet.

Regards

Paulo


----------



## GBurton

PCP said:


> Snap is a bad word to describe the movement but since you are using it:
> 
> *So what happens when that heel angle is reached? Does the fin keel boat just sit there, frozen in time?*
> 
> No, the boat will snap back almost as fast as it snap before on the opposite direction. When the light boat is already "snapped" back, the heavier boat is probably still rolling down slowly or perhaps it is starting slowly to come back to its feet.
> 
> Regards
> 
> Paulo


Still waiting for the damping explanation......


----------



## pvajko

PCP said:


> In a static situation without waves I don't know but recent tank testing showed that in a dynamic situation with waves the mast will help the boat to right itself up faster.


That's really odd, could you give us a link to that paper?

(I hate to mention, but Marchaj's book also references tank tests showing boats are more likely to capsize *without* the mast, but he is saying they'll be slower to recover *with* the rig because of it's dampening effect.)

Peter


----------



## PCP

pvajko said:


> Well, Paolo, I (the forum engine) quoted that from your own post, click on the little arrow in the quote box and you'll see.
> 
> But we seem to be talking about two different things. I'm talking about your tripping over the keel scenario where you seemed to say that the beamy, fin keel boat will slip sideways rather than roll over. That is, I think in contradiction with what Jeff said (today's fin keel boats have better dampening than full keels) because if a fin keel as at least as good dampening as a full keel, I can not see why would it slip more easily sideways, but again, I may be wrong here.


I am sorry.Yes, regards that quote it seems to be some confusion. When I read what you have posted :

*"Now, if a fin keel allows the boat to "rotate much easily" as you say, then how can it have a "much higher dampening moment" at the same time?.."*

I interpreted "rotate much easily" as a referring to a roll movement.

When I said that I was referring to rotating not on a horizontal axis (roll ) but on a vertical one. That has to do with the lesser resistance a much smaller underwater area will provide and also to the shape of that area: A long one along all the hull, in the case of the full keel and a central vertical one in the case of the Fin or foil keel.

It is clear that would be much more easier to make the fin keel to rotate around its keel than the full keel boat.

Everybody that tried to turn around on a marina or in a tight spot a full keel boat and a fin boat will know of what I am talking about.

Regards

Paulo


----------



## PCP

skygazer said:


> ...
> In science I learned that one can usually devise an experiment to get the results desired.
> 
> ....


If it was that way we would still be in the dark ages. It all depends on who makes the testing, amateurs interested in proving something or scientists trying to broaden knowledge on hydrodynamics. In this case it was the last one. The Tank testing was conducted in a main university by researchers.

Regards

Paulo


----------



## PCP

pvajko said:


> That's really odd, could you give us a link to that paper?
> 
> (I hate to mention, but Marchaj's book also references tank tests showing boats are more likely to capsize *without* the mast, but he is saying they'll be slower to recover *with* the rig because of it's dampening effect.)
> 
> Peter


Yes, I will give you the name of the paper and the University (I have to look) but you have to pay to access it or to receive the papers home.

But it is easy for you to mention what test tanking is Marchaj referring (just say the page and the chapter). To my knowledge all tank testing regarding sailboats stability was done after Marchaj book.

If I remember correctly he refers not tank testing under controlled conditions but what happened on the 1979 Fastnet . It was found that a boat after losing is rig was easier to capsize than with the rig intact.

Off course, without controlled conditions and without isolating causes saying that is due to a lesser roll moment of inertia is just a hypothesis that has to be confirmed with tank testing.

Personally I think that the reason is other and it has to be with a boat sailing or sitting on the water at the mercy of waves. With 40 or 50K winds even if you don't carry any sail, the boat is sailing, moving on the water with directional stability and much less at the mercy of waves.

There are some great images of an Open 60 on bare poles sailing at over 10K.

Regarding Marchaj's saying that a capsized boat will be slower to recover *with* the rig because of it's dampening effect, it is just an hypothesis that has to be verified under controlled conditions. It was what those researchers have done: Marchaj hypothesis is wrong, it is not in accordance with reality.

Regards

Paulo


----------



## Jeff_H

I am not 100% certain that Paulo and I are in agreement on all of this, in fact I am certain we are not, but that is okay. Through discussion I would expect that we will end up perhaps a little closer in our views. This is my understanding of some of the issues being discussed above. 

Starting with the issue of relative dampening force of a deep fin vs a shallower greater area keel. (Trying to avoid the semantics issue) The dampening force generated by a keel rolling through the water is proportional to the area of the keel, and the distance (from the roll axis to the center of the dampening) to the third power. So while a deep fin keel will have much less surface area than a traditional, because it has a significantly longer dimension from the roll axis to the center of the dampening than a more traditional keel it may actually develop greater dampening forces. 

The potential of a deep fin keel to produce dampening is somewhat mitigated by the fact that high aspect ratio fin keels of stall more easily than lower aspect keels and so potentially produce less side force per unit of area. That said, these types of discussions are hard to broadly generalize and the specific reality will vary with the specific design of the keel, boat and wave shape. In most larger-wave induced rolls, the side speed of the keels through the water is so great that virtually all keels are effectively stalled, and so the side force per unit of area may actually be the same between a deep fin and a shallower full keel. 

Further complicating this discussion is the shape of the keel, shape of the hull/keel intersection, and proximately of the keel to the hull. The more vertical geometry of a deep fin keel would result in the face of the keel operating more perpendicular to the flow of the water. In a stalled state that would produce a higher unit force. The area around the hull is highly turbulent during a roll, and might entrain more air, therefore producing less unit side force, and since a full keel has a larger portion of its keel in this region, it might be expected to produce a relatively lower unit side force. But because there is a gentler curve in this area of a traditional full keel, there is also likely to be less turbulence in the area of the keel to hull intersection, therefore somewhat mitigating the impact of the larger percentage of the full keel operating in this zone. 

Another factor that complicates this discussion is that traditional full keel boats tend to (but not always)roll at a slower rate than more modern designs (which tend to be lighter for an equal length). That slower roll rate means less turbulence and so a greater dampening unit force per area, but the keel passes through the water at a slower speed suggesting in reduced unit dampening force per area. 

(See why I say this is hard to generalize about and why I said 'may result in greater dampening') 

As a word about my personal opinion in these discussions, and in an effort to provide a filter which would help provide a fair minded sense of where my personal prejudices tend, when it comes to offshore cruising boats, I am not a fan of the Open Class style boats that Paulo likes. They are clearly faster than more moderate designs, but that speed comes at a price in terms of motion comfort and self-righting. 

While these Open Class based designs have demonstrated an enviable record as race boats, and may even be a reasonable basis for coastal cruisers, I personally prefer more moderately narrow beam boats for distance cruising containing significant amounts of offshore use. 

Which brings me to the issue of boats in waves and GBurton's question about what happens when that heel angle is reached? Does the fin keel boat just sit there, frozen in time?

I think that these questions have little to do with the keel type, and everything to do with form stability. Fin keel or not, a high form stability boat will want develop a greater force trying to make it heel parallel to the plane of the surface of wave. All other things being equal, a higher form stability boat will tend to move more in sync with the wave face. (Not a good thing in big waves) 

To one degree or another, mitigating against that is the tendency of modern deep fin keels with bulb designs to have a proportionately high righting moment due to very low centers of gravity. And also mitigating against the impact of form stability is that deep fin keel boats tend to develop very high roll moments of inertia relative to their displacements often having roll moments of inertia similar to much heavier displacement boats. That would tend to slow the roll rate some, but of course not as much as would be the case of a more moderate beam design, in other words a boat with less form stability. 

As I said earlier, in big waves, a large roll moment of inertia does two things, at the top of the wave, it delays the rotation of the boat relative to the rotational force. A good thing, but at the bottom of the wave, its greater stored kinetic energy, tends to cause it to get out of phase with angle of the wave face and continue to roll as the bottom of the wave flattens out so that there is a greater danger of dipping a spar in the water (never a good thing). At the bottom of the wave, the boat with greater form stability would generate more righting force, remaining in sync with the wave surface and so would be less likely to dip a deck or spar or keep rolling as far as a boat with a high roll moment of inertia and/or less stability. 

I am running out of time but I also want to touch on the issue of inverted stability. Pretty much any reasonably normal sailboat of most eras of history, placed in perfectly calm water exactly upside down, will remain so. When you talk about a boat with a large angle of positive stability, it simply means there is a smaller angle at which it is stable inverted. But since it requires wave action to invert almost any reasonably safe design, there is usually some wave action trying to rotate the boat past the point that it again starts to develop positive stability. When you talk about traditional designs, or more moderate modern designs (either with an LPS approaching 150 degrees), this can happen at inverted heel angles as small as 25 to 30 degrees. But when you consider a design like the open class boats, with the keels centered, the limits of positive stability can be down in the 125 degree range. 

What is impressive to me about the video is that the inverted Open Class boat with its keel canted, begins to develop positive stability at an angle which appears to be somewhere around 15-20 degrees. That is amazing! But to me, in my personal opinion, having to cant a keel of an inverted boat to right the boat is no way to go cruising, especially if you visualize the potential weight shift in an inverted distance cruiser. 

Lastly there is the question of the impact of the mast on righting. Like most of this, this discussion point is complex and situational. As someone said above, the reason that a mast may be seen as being helpful to righting a boat is that in a large enough wave situation that a boat can be knocked into an inverted position, the mast being deeper into still water, acts a very deel keel so that the force of the wave is amplified and there is more force exerted to rotate the boat toward upright. But that is in part offset by the ballast affect great weight of the sails and rig below the surface, and damping resistance of trying to move the sail sidewards through the water once positive stability is achieved. 

There is also a thought that few boats will survive a roll to inverted with their rig intact. The flat water test, therefore is supposed to demonstrate what happens in most likely condition, (inverted without rig) and the hardest to re-right (inverted without wave action to re-right). I am not sure that I buy that, but that is my understanding of the rationale. 

Cheers….


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## pvajko

PCP said:


> But it is easy for you to mention what test tanking is Marchaj referring (just say the page and the chapter). To my knowledge all tank testing regarding sailboats stability was done after Marchaj book


See attached.

Now let us see your paper.


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## PCP

The paper I was referring is from the Australian Maritime College. I cannot post it since it not free but I guess I can post this one By Richard Birmingham from the School of Marine Science and Technology, Newcastle University, UK (2004). On this paper he explains why a boat with an intact mast returns easily to its feet:

Another result of recent research has caused considerable discussion due to its unexpected nature:

Should a capsized vessel retain its rig intact it is usually assumed the damping effect of the rig would impede any action tending to right it. In theory a vessel capsized by breaking waves may be righted again by another wave with similar energy. However as the mast in the water would have a damping effect not present if the vessel had been dismasted it has been assumed that this would slow the righting action.

Experimental result from the towing tank in the Australian Maritime College, Tasmania, found that a dismasted vessel required more waves to right it than
the vessel with the intact rig . ... the effect can be demonstrated, and it is argued that the damping effect is in fact helping the righting process.

The explanatory theory is that the breaking wave force the hull of the vessel at the surface sideways (in sway), while the rig, deeper in the water is
left behind. After the wave has passed the vessel starts to return to 180 degrees of heel (i.e. fully inverted) but the damping effect of the mast slows this such that it is still heeled when the next wave arrives. Each wave arrives with the vessel at a reduced angle of heel (160 degrees, 140 degrees etc.) until the angle of positive stability is reached, and the vessel re-rights.

In contrast the dismasted yacht returns to 180 degrees more quickly, so the progressive righting process does not occur.

Off course this is pretty meaningless other than from the theoretical point of view because almost all sailing boats break the mast when rolled to the inverted position.

There is a small lapse on this paper: when it is said :

*"In theory a vessel capsized by breaking waves may be righted again by another wave with similar energy. "*

This would only be true if the area under the positive part of the RM curve was equal to the area over the negative part of the RM curve, or saying in a simpler way if the energy required to capsize a boat was the same as the energy to roll it back to its feet.

A modern sailboat stability curve has almost always at least 2 times more area under the positive part and many times about 3 times more positive area.

This means that almost any sailboat will only requires a wave with half the energy of the one that capsized it and many will requires only about 1/3 of the that energy to get back to its feet.

Paulo

...


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## pvajko

That sounds very interesting Paolo, that is what I was asking for all the time, *scientific* evidence proving Marchaj was not always right.


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## PCP

pvajko said:


> See attached.
> 
> Now let us see your paper.


Those photos are from the Wolfson unit tank testing on a work directed by Claughton that gave origin to the paper "THE DYNAMIC STABILITY OF SAILING YACHTS IN LARGE BREAKING WAVES" and yes it is from 1984. My bad I had the idea that it was from the early 90's.

The work of Marchaj about Seawothiness was also from the 80's but posterior to that tank testing. Probably I was influenced by the age of Marchaj that was most of its work published in the 60's and 70's (we was born in 1918).

I am familiar with that paper and on that tank testing they did not test (I had a quick look to confirm) capsizing with a mast and without a mast and much less return from an inverted boat to its normal position with a mast and without a mast.

What is said on that picture is that they tested the capsize of sailboats without masts and Marchaj suggests as a non tested hypothesis that a sailboat would be harder to return to its feet if it had a mast.

Well, Marchaj was wrong about that. Much more recent tank testing (specifically over that subject) showed that it was the opposite.

Regards

Paulo

...


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## pvajko

PCP said:


> I am familiar with that paper and on that tank testing they did not test (I had a quick look to confirm) capsizing with a mast and without a mast


Looks like Marchaj did , see this figure on the left.

Peter


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## Lou452

This is so far one of the best threads on sailnet but it has not pushed me to pick a winner between full and fin keel. Could you all name types of heavy weather boats that shed water come back upright and fend for themselves? Full or fin or does it have more to do with the sailor than the boat? Thanks for some great reading.


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## blt2ski

Lou,

There is another sticky thread somewhere with one persons "bluewater" boat list. Even that list draws critiques if you will, as that person has a particular set of what the boat should have to be bluewater! As such, a boat may be built to the correct scantlings, but be 20 gals short of water and fuel, and NOT make the list due to insufficient stock water and fuel tankage.

Reality is, there are many boats with ALL types of keels that will survive, roll correctly if you will.........

marty


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## Faster

Lou452 said:


> .... Full or fin or does it have more to do with the sailor than the boat?... .


This discussion is one area where the poor hapless sailor involved cannot really be a factor anymore. Whether the boat will right itself smartly or eventually is subject to many factors including the design, condition of the boat at the time (holed or not?), sea and wind conditions, and perhaps a good dollop of luck (or lack thereof)..

Where the sailor is during the event is yet another factor.. locked below? on deck and 'hanging on for dear life'? underwater at the end of a tether? knocked free and floating away? Conscious? Not part of the full/fin debate, obviously, but part of the overall outcome.

This is a decision that most make on another 'many factors' basis. Speaking personally I like a boat with good weatherly performance, will move in light air, with an interior I can comfortably live aboard for months at a time. I also really appreciate a boat that will back up predictably in close quarters maneouvering, which pretty much eliminates a full keel, or even most long keel/skeg rudder designs ( I LOVE the Passport 40, for example, and it would be way up my list for offshore sailing, but not for BC coastal cruising...)

And it's another one of those areas where one camp will never convince the other.. but if people reading it all learn something from it, or at least take away a balanced view of the issue then I suppose that's all to the good.


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## PCP

pvajko said:


> Looks like Marchaj did , see this figure on the left.
> 
> Peter


That is a theoretical study of the capsizing possibilities based on the maximum angle of roll with and without a mast regarding roll moment of inertia. What that graphic shows is that according with his calculations the boat without a mast can roll to the point of capsizing while the boat with a mast remains safe. That was not tank tested or tested in any other way

As I have said the results of those tank testing sessions were published by Claughton and they did not experiment with boats with masts and without masts, much less regarding the influence of a mast in an inverted boat regarding the righting itself up, that was my point anyway.

The results of those tank tests were a bit deceiving and results showed that there was not a big difference between the 3 different types of hulls they have tested. A relatively small breaking wave could capsize any of the boats. Also showed that a significant increase in weight of the boat make no significant difference.

I guess that now, almost 40 years after those tests, with the evolution of computer naval software and tanks, there is conditions to testing with much finer detail but tank testing is very expensive and that kind of research would cost a fortune that nobody is willing to pay.

Regards

Paulo

...


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## skygazer

skygazer said:


> *In science I learned that one can usually devise an experiment to get the results desired. *
> 
> A mast will hang down deep, well below the wave action, in deep still water. So if beam on, the waves could carry the hull along while the mast stays behind, thus in effect starting the roll towards righting.
> 
> But generally a mast and rigging stabilize the rolling of the hull, so generally it would greatly slow the rolling back from an inverted position. If the boat was not beam on to the waves, I would think it would have to wait until (and if) wave action slewed it around to beam on. A rogue wave may not have another behind it strong enough to push the hull beyond the mast. If wind capsized the boat, the waves might not be strong enough, and lacking the leverage of the mast, the wind will slide over the hull.





PCP said:


> If it was that way we would still be in the dark ages. It all depends on who makes the testing, amateurs interested in proving something or scientists trying to broaden knowledge on hydrodynamics. In this case it was the last one. The Tank* testing was conducted in a main university by researchers*.
> 
> Regards
> 
> Paulo


Unfortunately I was referring to University researchers. I was a science "nut" until I got to university and found out that 90% of people in science are just doing a job. The research is under a professor, but carried out by graduate students - using undergrads for help. They know the results desired by the organization providing the funding. There is no "pure science" any more, don't believe all that you hear. We are in many ways in the dark ages, due to funding and politics.

Do I have a good scientific mind? Compare what I decided by viewing the physical problem of the "inverted boat with mast" in my mind. It matches exactly what your paper reported, except I go further because I've seen wave tanks and know they can make identical pure waves and control the orientation of the boat, unlike in real life.


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## mitiempo

skygazer said:


> If wind capsized the boat, the waves might not be strong enough, and lacking the leverage of the mast, the wind will slide over the hull.


Wind alone will not capsize a boat. It will knock it down but when the boat is at around 90 degrees the keel will produce a large righting force and the boat will not go over any farther. It takes waves to pass that point.


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## jackdale

mitiempo said:


> Wind alone will not capsize a boat. It will knock it down but when the boat is at around 90 degrees the keel will produce a large righting force and the boat will not go over any farther. It takes waves to pass that point.


And the effective sail area is zero.


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## skygazer

mitiempo said:


> Wind alone will not capsize a boat. It will knock it down but when the boat is at around 90 degrees the keel will produce a large righting force and the boat will not go over any farther. It takes waves to pass that point.





jackdale said:


> And the effective sail area is zero.


Totally agree with both of you, poor choice of words on my part. As you heel the wind has less and less to grab, thankfully.

I meant that if the waves alone did not do it, and a gust of wind (in combination with the wrong wave) was a factor, than it might take longer for a lucky wave to right the boat.

But sooner or later the right, or wrong, wave will come along. Nature rarely has pure waves. Wave motion seems simple, but wave interaction is wonderfully complex.


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## Lou452

As I will try to look for a boat that will fit my needs first I need to figure out what that need is right now the 13 ft flying junior fits me. I was going to buy from a 16 to 26 foot looking at what could be pulled down the road. already looking at dreaming of the next boat. Do others do this? This kind of leads away from a fin I am in KY no huge waves here. I grew up on Lake Eire feel just fine on that water any summer wind or wave in my sunfish. Still this is not blue water. I plan to move but for now I am here. Next boat for here sailing in the lakes should be? I Like to scuba dive play on the beach . I would like to get on and in the water easy from the boat. From what I am learning about fin vs full a full keel shoal draft might fit my needs better? The next boat should be? Also I could get a slip an go up to say 36 foot but this would be a boat that would have to make the move with me and the move is 8 years min time frame away


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## blt2ski

Lou,

From what you have described, it would be neither fin or full, but a "centerboard!" IE, this can get very close, if not beached, if it has a swim platform, you can get in and out easy from the water.........

The question on which keel to get, is not as simple as this or that. Reality is, one needs to know also where they will sail, use the boat etc. From what you described, it would be a centerboard, or possibly a wing/shoal fin or the scheel fin that was mentioned too. The Centerboard is the only one that is beachable or able to go into really shallow water.

It should also be pointed out, all of these models have potential stability issues on par to somewhere in the middle, or completely different than already mentioned in this debate.

Marty


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## PCP

mitiempo said:


> Wind alone will not capsize a boat. It will knock it down but when the boat is at around 90 degrees the keel will produce a large righting force and the boat will not go over any farther. It takes waves to pass that point.


Waves and not any wave but a breaking wave

Regards

Paulo


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## PCP

skygazer said:


> Unfortunately I was referring to University researchers. I was a science "nut" until I got to university and found out that 90% of people in science are just doing a job. The research is under a professor, but carried out by graduate students - using undergrads for help. They know the results desired by the organization providing the funding. There is no "pure science" any more, don't believe all that you hear. We are in many ways in the dark ages, due to funding and politics.
> 
> Do I have a good scientific mind? Compare what I decided by viewing the physical problem of the "inverted boat with mast" in my mind. It matches exactly what your paper reported, except I go further because I've seen wave tanks and know they can make identical pure waves and control the orientation of the boat, unlike in real life.


You cannot know about the seriousness of that tank test without reading the paper do you?

I found out a free version of that paper posted when it was presented at the Chesapeack symposium in 2005. It is a reduced version but I think it is enough for you to evaluate the seriousness of the work and the validity of the results:

http://eprints.utas.edu.au/6670/1/17th_CSYS_Binns_and_Brandner_2005_F2.pdf

To be trustful I have to say that when I heard about this results showing that an inverted boat with a mast will re-right itself faster than without a mast I had a similar reaction, I mean disbelieve but after reading the paper and looking at the methodology that they implemented in testing I was forced to change my opinion....and it was not only me that had a hard time in believing the results, the research nautical community had the same concerns. The tests were repeated in other places and the results validated.

It has all to do with tripping, in this case the yacht will not trip on the keel bu on the mast

*"That is, if the roll moment experienced by a yacht when undergoing sway velocity is a tripping moment (tending to turn the higher portions of the yacht into the direction of travel), then the chance of rerighting can be seen to be increased. This correlation exists because when hit by a breaking wave, a yacht will experience significant surfing even whilst inverted. The surfing will continue long enough after the wave has passed, due to the yacht's inertia, and so the probability of re-righting will be significantly increased as the tripping moment is increased. "
*

Regards

Paulo


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## pvajko

PCP said:


> That is a theoretical study of the capsizing possibilities based on the maximum angle of roll with and without a mast regarding roll moment of inertia. What that graphic shows is that according with his calculations the boat without a mast can roll to the point of capsizing while the boat with a mast remains safe. That was not tank tested or tested in any other way


No, Paolo, Marchaj writes on page 224 that Fig. 111. refers to capsizing *tests* made in the USA (honestly, I'm getting tired of scanning the book every time you tell me it's not true what I'm writing, I guess you have the book yourself, or you can download it from the link you posted earlier here)


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## PCP

Jeff_H said:


> I am not 100% certain that Paulo and I are in agreement on all of this, in fact I am certain we are not, but that is okay. Through discussion I would expect that we will end up perhaps a little closer in our views. This is my understanding of some of the issues being discussed above. &#8230;.


Ok, lets see what we can do about this.



Jeff_H said:


> While these Open Class based designs have demonstrated an enviable record as race boats, and may even be a reasonable basis for coastal cruisers, I personally prefer more moderately narrow beam boats for distance cruising containing significant amounts of offshore use. &#8230;.


Me to, but this has to do with personal taste and nothing to do with the suitability of those designs (based on Open boats) for offshore use in what regards seaworthiness.

Most boats based on Open boats are not fast light boats and the ones that are light are for more frugal cruisers than me, or are richer and have money for a bigger boat.

Cruising in fast performance boats of this type imply to live in a very frugal way due to the light load capacity and to the simple interior. For living with the same comfort and carrying load of a more traditional cruiser you will need a bigger boat, and that costs more money.

But aside that, Open boats were design not only for offshore use but for solo offshore use. They are very forgiving boats and very safe boats.

I have already show to you that a 40 class racer has a better stability curve than a Vaillant 40, in what regards AVS and in the proportion between the energy needed to capsize the boat and the energy needed to re-right the boat when inverted, or putting in another way, in the proportion of the size of the wave capable to capsize the boat compared with the size of the wave that will re-right the boat. These boats can be not only easy but very seaworthy.

But of course, in what regards cruising boats based on these designs each case is a case and as in any other sailboat it is better to have a good look at the stability curve. That is not different than with any other sailboat, beamy or not. I know of some good narrow boats with a stability curve not as good as some of these boats in what regards AVS and in the proportion between the positive and negative part of the curve, not to mention the righting force at 90º.



Jeff_H said:


> As a word about my personal opinion in these discussions, and in an effort to provide a filter which would help provide a fair minded sense of where my personal prejudices tend, when it comes to offshore cruising boats, I am not a fan of the Open Class style boats that Paulo likes. They are clearly faster than more moderate designs, but that speed comes at a price in terms of motion comfort and self-righting. &#8230;.


Regarding this some confusion and some disagreement.

As I have said before many times for my personal use as a cruiser I prefer more classical boats and not boats derived from Open boats. If I could chose a cruising boat I would chose a XP 38 that is not a beamy boat neither a boat based on Open boats.

That does not mean that I don't like Open class boats as I like many other types of boats. I can appreciate and understand their advantages and weaknesses and I have posted already about it.

The disagreement :

I don't consider that boats based in Open class style boats are faster than other modern boats based on more traditional rule like IRC or ORC. Actually only downwind in very heavy conditions a racing Class 40 will be more fast than a racer like a Ker 40. Even in what regards fast performance cruising boats a ker 39 will beat any fast cruising boat derived from the Open classes, the same way a Volvo60 will beat an Open 60.

So what is the advantage?: The easiness of use. You need a crew and a good one to race a ker 40 (or a Volvo), the boat is very nervous and need a constant trim especially downwind while an Open boat is designed to go downwind on autopilot. Upwind, the Ker 40 will slam less and will be more faster but it will be a more nervous boat with less form stability and a less stable platform.

It will be more easy and safe to leave the boat on autopilot and go forward in a class 40 then in a ker 40 type of boat (more narrow and with a huge ballast/displacement ratio).

The ease of use is the main reason that motivates the designers to base their cruising boats on the type of hulls of the Open boats. After all most cruising boats are sailed solo or with the little help of a wife that is not normally much, so what better model could they have than the type of hull of a boat that is designed just to be sailed offshore solo and have been improved through the years?

And I don't mean only performance cruisers like the Pogo, but almost all modern designs by all the main Na and main boatbuilders: Beneteau (Sense and Oceanis), Hanse, Jeanneau, Bavaria, Dufour, just to name a few.

I agree that advantages (not the speed) comes with a price in what regards motion comfort upwind with waves but I completely disagree in what regards a lesser ability to self-righting.

That it will depend on each boat but as a rule I don't think that is true. Generally the AVS of these boats is not lower than the previous boats from the same brand with a narrower hull, but the overall stability is bigger.

Putting in another words, the wave energy needed to capsize these boats is bigger than on previous less beamy models and the proportion between the wave capable of capsizing the boat and the wave capable or re-righting is about the same. As an important bonus these boats have more RM at 90º.

How was this possible? Look at the keels and the drafts. The B/D ratio is about the same but now almost all the keels have more draft and more weight on the bulb, some fast cruising boats have fin torpedo keels and their number is increasing.

You pointed to me once a Claughton paper that related capsizing resistance with beam and that is logical in fact. A wide cat is much more difficult to capsize (with no sails) that any monohull with the same size. So these boats have advantages in what regards positive stability and also in what regards dynamic stability : their keels have much less area than the previous ones and that and beam will make these boats harder to trip on the keel and will make them more able to dissipate the wave energy with any other movement than not a rolling one.

There is a good reason for all main boat builders and main yacht designers going on this direction. I still prefer a boat with better tracking ability upwind and with a better motion in waves upwind, but understand the reasons that makes most sailors prefer other type of boats. Many don't sail much upwind or with waves

As I have explained elsewhere I think these boats based on Open boats make a lot of sense if you will sail extensively upwind and want a forgiving boat that don't heel much. These boats will be very adequate for voyaging with the trade winds that is the way most of the cruisers sail when crossing oceans.

About the rest, I will try to reply in another day, with more time.

Regards

Paulo


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## GBurton

Note to self: Never, ever get in a discussion with Paulo ever again. 

Its like listening to an interview with Macho Man about why he is better than Hulk Hogan


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## wolfenzee

jackdale said:


> So far so good.
> 
> A full keel will generally track better dead down wind. Full keel boats tend to have a smaller draft allowing them to get into shallower water. But as you inferred, they do not tend to point as well as fin-keels. They also need more speed to get steerage way.


I don't known what you mean by that my boat will point 35degrees off the wind with main and working jib {better with cutter rig). It tracks well on any tack and doesn't require as much attention to the helm to keep on course as a fin.


















This boat was designed by William Atkin in 1936...before the marketing industry tried to convince people that boats based on racing boats make good cruising boats...presumably because they are faster. BTW this boat is fast, sea kindly with a pleasant motion.


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## Lou452

Hey men Please keep the debate going !!! Some of it is over my head but You all keep at it ! BE nice others are looking at you. We might learn a thing or two. Lets get some more data How many full keel boats built are on the bottom and how many fin keels have been laid to waste. Try to find some way of apples to apples hard to match a 1928 wood full keel up to a 2002 fiberglass fin keel. Want to add just read Cats may not be allowed off shore in anything less than calm weather In the USA unless crew and boat meets standards to be set. Check out that news. It is off subject of fin and full Put it in because cats came up in thread. Once more keep it up. This is a good thread!


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## skygazer

Lou452 said:


> As I will try to look for a boat that will fit my needs first I need to figure out what that need is right now the 13 ft flying junior fits me. I was going to buy from a 16 to 26 foot looking at what could be pulled down the road. already looking at dreaming of the next boat. Do others do this? This kind of leads away from a fin I am in KY no huge waves here. I grew up on Lake Eire feel just fine on that water any summer wind or wave in my sunfish. Still this is not blue water. I plan to move but for now I am here. Next boat for here sailing in the lakes should be? I Like to scuba dive play on the beach . I would like to get on and in the water easy from the boat. From what I am learning about fin vs full a full keel shoal draft might fit my needs better? The next boat should be? Also I could get a slip an go up to say 36 foot but this would be a boat that would have to make the move with me and the move is 8 years min time frame away


Hello Lou, here is some of my experience on lakes. Centerboards are great, you can find the hidden shallow spots with the board down, just pull it up to get off, or it will just bounce off. Here in Maine the lakes were all raised for logging by dams. In fresh water wood doesn't rot, so there are stumps over 100 years old still down there with the sunken logs. I hit a big stump pretty far from shore with my center boarder, taught me I should never sit on the trunk, because the board kicked up the handle, which would have been between my legs  I avoid that area, I took rough sightings.

Now I know the bad spots on "my" lake, and am using a Victoria 18 there. I don't want to go much bigger, the lake is only 7 miles, and very narrow. The V18 has a fixed long lead filled shoal keel. My wife loves it, much more stable. However, be aware that you must anchor and swim to shore, or we sometimes use an inflatable and paddle in. This is not a problem for us, we never beached anyway because wave action works the boat against the shore. We always carry an anchor, and a light anchor to keep the stern from swinging. Here in Maine sand beaches on lakes are rare, there is much granite everywhere so again, we never think of beaching. To get in and out of the water a folding swim platform can be good, and a cheap ladder with hooks that you put on and off is OK, and below when not using it.

I'm sure a fin keel would be fast and fun, you might need to stay in deeper water. Harder to trailer and harder to launch without a deep steep ramp. Look for a depth map, fisherman at least make them. Mark off the areas that are too shallow for whatever fixed keel you look at, and decide if you are happy to give up going to those areas.

There are also swing keels (heavy swinging keel) which could be good, and shallow keels with small centerboards inside, maybe the best of both worlds? An example for sale here is a 23ft Seafarer Kestrel, very trailerable. SEAFARER 23 KESTREL (DAYSAILOR) sailboat specifications and details on sailboatdata.com

I purchased last fall and have not yet sailed a Seafarer 24, which has a weighted lead bottom with a slightly heavy swing keel/centerboard. Because the main part of the lead is up high, it can't be as good as a deeper keel, it is not an off shore boat, but probably great in the lakes around here.

To summarize, decide how much of the lake you are willing to give up (depthwise) to determine your acceptable fixed keel depth. Check your ramps by measuring how far out you need to go to launch. You can use an extension, but check for the "standard" deep hole right at the ramp end where prop wash digs out the bottom when powerboats power onto their trailer. Don't run your trailer wheels into that hole if too deep.

We like trailering for lakes, because we can go to new areas for variety and interest. And work on the boat at home, and no fees.

Edit: I almost forgot. Make sure that whatever boat you get to trailer has a hinged mast tabernacle on the cabin top, with support under it. Do not get a keel stepped mast, very much harder to step and unstep.


----------



## PCP

Lou452 said:


> ... Want to add just read Cats may not be allowed off shore in anything less than calm weather In the USA unless crew and boat meets standards to be set. Check out that news. It is off subject of fin and full Put it in because cats came up in thread. Once more keep it up. This is a good thread!


That's odd. Are you sure? Do you mean that all cats will be "grounded" inshore till they prove to meet standards that had not even been set?

That is crazy. It is hard to believe!!! Any link to that?

Regards

Paulo


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## mitiempo

Skygazer

The Seafarer 24 CB, as with most boats built with the option of a centerboard or a deeper keel, has more ballast to compensate for the higher location.


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## mitiempo

Cate not allowed offshore? That is crazy. There are probably a great many more unseaworthy monohulls than cats.

Do you have a link?


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## Lou452

PCP said:


> That's odd. Are you sure? Do you mean that all cats will be "grounded" inshore till they prove to meet standards that had not even been set?
> 
> That is crazy. It is hard to believe!!! Any link to that?
> 
> Regards
> 
> Paulo


Paulo : at this other sailing web site( cruisers and sailing ) you will find some info. I did not spend a lot of time on this because I think it is nuts. Some folks say anything and put it on the web. Maybe I should not have even repeated it because the more times rumors are told they gain stature. They were very serious with the fourm. I try to spend time in fourms that debate with class and put out a good set of facts Plus a cat boat is not me I love my little sunfish even in Lake Erie with White caps and surf. I am close to the water if I lose it and I can get back up. I can not say for sure becase I have not done it but even a small cat looks like a man could go for a good flight and the boom might hurt bones when you land. Then you have to get it back up. I used to jump the ramp on water skis and trick ski. Water can get kind of hard when you hit it that I can say for sure. Full or Fin looks like a knock down would be less violent than in a cat ? I have little sailing knowledge but this thread and other members that are helping me plus books I am reading are starting to make sense. The best thing is geting to spend time on the water to see how I fit with doing it. I can tell you all kinds of ways to move a soccer ball but you must find somthing that works for your limits to the game. I need to find and live in my sailing limits. Most all of the boats are better than me so I need to learn enough to make good choices LOU452


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## PCP

Lou452 said:


> ...Water can get kind of hard when you hit it that I can say for sure. Full or Fin looks like a knock down would be less violent than in a cat ? I have little sailing knowledge but this thread and other members that are helping me plus books I am reading are starting to make sense. The best thing is geting to spend time on the water to see how I fit with doing it. I can tell you all kinds of ways to move a soccer ball but you must find somthing that works for your limits to the game. I need to find and live in my sailing limits. Most all of the boats are better than me so I need to learn enough to make good choices LOU452


That's about it I know of guys that have crossed the Atlantic on Beach cats, or sailed the Horn...and they were not crazy but great sailors and were doing something that carried a limited risk. If I tried that it would be madness. I don't have the knowledge neither the skills to do that on a beach cat. However a cruising cat is not properly a beach cat. Here you have a Lagoon 440 sailing with winds in excess of 40K:






The guy is very good or a bit crazy because he carries too much sail for a relaxed sailing. With a bit less sail he would not be doing 18K but would go at 14K in a much safer way.

Regards

Paulo


----------



## PCP

Lou452 said:


> Paulo : at this other sailing web site( cruisers and sailing ) you will find some info. I did not spend a lot of time on this because I think it is nuts. Some folks say anything and put it on the web. Maybe I should not have even repeated it because the more times rumors are told they gain stature. They were very serious with the fourm. .


I saw what you mean...it is a 1st of April lye. Very funny

Regards

Paulo


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## wolfenzee

My full keel boat was commissioned to be a single handed ocean cruiser, fast sea worthy and easy to handle on all points of sail, granted there isn't enough room to swing a cat, but I don't have cats on board and I choose grace over space. A friend of mine in talking about his Catalina 30 (a fin keel boat) commented that even though it took a lot more work to sail at sea and wasn't as "sea kindly" his wife likes the extra room. If you are wondering which boat will be easier to handle at sea a full keel wins hands down...that said some will not get out of their own way in a calm and not all point well...but this also applies to to some fin keel boats. Some of the best ocean cruiser designs are "old school" designs which some consider to be obsolete because they do not emulate modern day racers as closely. I would take my boat to sea ahead of 95% of the boats in the harbor...she is safe, easy to handle, comfortable and tracks well on all points of sail...tending the helm is relaxing (some of the fin keels out there require 100% of your attention at all times) and the tiller can be lashed rather than using high tech gadgets and gizmos.


----------



## souljour2000

What kind of boat Wolfenzee?...i just was lucky enuff to obtain a Columbia 40 for the right price...she needs lots of deck re-hab...but otherwise seemed a good bet as her rigging, spars and engine and sails are good from what I can tell...I know there will be a few surprises.... but she has a partial full keel and C/B.

Keel has 8,400 lbs lead...and C/B can drop her draft to 9 feet...4.5 feet when board is up. Charlie Morgan design..(1964) for Columbia and only 10.5 beam..plenty of room but sea-kindly lines...What I am getting at is hearing you talk about your old girl makes me itch to see how this boat handles...(wheel-steering) but also "emergency tiller" access plate at rudderpost head...
I can't wait to see how she tracks...after reading your post above...standing on her deck mid-river with gusts to 20 mph she seemed to almost not move..back to the tracking..,interested to see if I can "lash off" the helm easily like you spoke of... instead of flirting with the autopilot(if it works) or self-steering(doesn't have..maybe doesnt need?)
Anyways..I am in love and lust..can't wait to get her near me..she's lying 80 miles away...awaiting P/O to send fuel injectors he already purchased...(already has new injector pump he installed)...and it's a 1988 engine Universal diesel 24 hp(kubota) ..a little underpowered for a 19,000 lb boat but... it seems is just a marinized version of kubota tractor engine that should be easy to get stock parts for from local kubota tractor dealerexcept for some certain ones...


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## skygazer

Wow, souljour, I just went to sailboat data COLUMBIA 40 sailboat specifications and details on sailboatdata.com and checked out your boat, looks really good. I'd love to try out a keel/centerboard.

Drop that board to 9 ft. and seems you could go upwind nicely, plus track downwind with the keel.

Wolfenzee, your boat sounds great, I really like the lines. I've only really been (sailing) on wooden full keel boats, so I'm not sure how the fins handle. I've been on one, but they only motored


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## wolfenzee

souljour2000 said:


> What kind of boat Wolfenzee?...i just was lucky enuff to obtain a Columbia 40 for the right price...she needs lots of deck re-hab...but otherwise seemed a good bet as her rigging, spars and engine and sails are good from what I can tell...I know there will be a few surprises.... but she has a partial full keel and C/B.
> 
> Keel has 8,400 lbs lead...and C/B can drop her draft to 9 feet...4.5 feet when board is up. Charlie Morgan design..(1964) for Columbia and only 10.5 beam..plenty of room but sea-kindly lines...What I am getting at is hearing you talk about your old girl makes me itch to see how this boat handles...(wheel-steering) but also "emergency tiller" access plate at rudderpost head...
> I can't wait to see how she tracks...after reading your post above...standing on her deck mid-river with gusts to 20 mph she seemed to almost not move..back to the tracking..,interested to see if I can "lash off" the helm easily like you spoke of... instead of flirting with the autopilot(if it works) or self-steering(doesn't have..maybe doesnt need?)
> Anyways..I am in love and lust..can't wait to get her near me..she's lying 80 miles away...awaiting P/O to send fuel injectors he already purchased...(already has new injector pump he installed)...and it's a 1988 engine Universal diesel 24 hp(kubota) ..a little underpowered for a 19,000 lb boat but... it seems is just a marinized version of kubota tractor engine that should be easy to get stock parts for from local kubota tractor dealerexcept for some certain ones...


Atkin & Co. - Captain Cicero
Designed by William Atkin in 1936, the rig was modified boom was cut down from 18ft and raised, foot is now 15ft with a 37ft luff, permanent back stay was added (keeping the running back stays), cap shrouds and spreaders were added to the existing lower and intermediate shrouds, head stay was made detachable so a larger sail could be flown on the top stay ( a pad eye on deck was added so the head stay and top stay are parallel making it a cutter rig), head stay luff 29' top stay luff 40', mast is 3 piece laminated Sitka spruce 45' head off the water. The boat was designed to have an Atomic 4 but was re-powered with a Vetus M415 (33hp Mitsubishi based diesel) with a 16" three bladed prop...a 2200rpm the stern is squatted down and the boat moves at 7knots using less than 3/4 gph. 3200lbs of lead with an 1000lbs added in the form of a lead shoe. A boomkin was added at onetime for a self-steering vane but the it was discovered she will sail for just fine with a lashed tiller. 
I have done a complete rebuild of the cabin, added two-speed winched to the two single speed that are there, new standing rigging and replaced the tired old SS chain plates with 954 bronze...beefier and will hold up better.


----------



## PCP

wolfenzee said:


> My full keel boat was commissioned to be a single handed ocean cruiser, fast sea worthy and easy to handle on all points of sail, granted there isn't enough room to swing a cat, but I don't have cats on board and I choose grace over space. A friend of mine in talking about his Catalina 30 (a fin keel boat) commented that even though it took a lot more work to sail at sea and wasn't as "sea kindly" his wife likes the extra room. ....


Has have been pointed out the cost of a boat and partly its seaworthiness have to do with weight. you should compare, as Marty as done, your boat with a boat of a similar weight, not length.

If you do that the story would be completely different in what regards interior space, seaworthiness, speed and even sea motion. Your boat has the advantage of mass for length (for the ones that prefer that kind of motion) but the big disadvantage of a much shorter LWL and that, as also have been pointed out, is very important in what concerns wave passage and the pitching movement of the boat.

Regards

Paulo


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## wolfenzee

PCP said:


> Has have been pointed out the cost of a boat and partly its seaworthiness have to do with weight. you should compare, as Marty as done, your boat with a boat of a similar weight, not length.
> 
> If you do that the story would be completely different in what regards interior space, seaworthiness, speed and even sea motion. Your boat has the advantage of mass for length (for the ones that prefer that kind of motion) but the big disadvantage of a much shorter LWL and that, as also have been pointed out, is very important in what concerns wave passage and the pitching movement of the boat.
> 
> Regards
> 
> Paulo


This is a comparison between fin and full keel, the biggest difference between fin and full keel boats is that fin keel boats are much lighter, that is the point...to compare boats of the same size and different weights is a more accurate comparison...a typical weight fin of the same size as a typical weight full is about half.


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## skygazer

While cleaning my office today to avoid starting taxes, I happened to read the back cover of an old "Practical Sailor" magazine, Sept. 2011.

Because I've been thinking about fin keels and bulbs, which sound very good, I was immediately struck by the following quote:



> ". . . I'm considering going to all-chain (rode). Also, because my boat is pretty light with a fin keel and bulb, *the rode wraps around the bulb *when the current is stronger than the wind, requiring diving to free the mess. This is manageable in July, *not so fun in October*."


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## blt2ski

Either way to look at a comparison, but it wt vs wt, or length vs length, You will probably get a figure/act to work in you favor. I'm sure I could take my boat compare it to a full keel of the same 28' deck length, it would weight in some 3-4K lbs more, the comfort ratio would be higher due to the higher wt. Just as generally speaking, a longer boat of the same disp is usually better at a comfort ratio than a smaller boat. 

The issue skygazer is talking about, occurs on bulb keels, but not other non bulb keels, be them fins, full, centerboard or bilge keeps. The issue is the bulb! On the otherhand, I doubt a bulb with all chain rode is going to have the same issues as a line rode anchor system either. Again, comparing two things that are not the same, in which, either way you look at it, you can get or not get the answer you are looking for. 

Anchor sizing seems to be another hot topic, as is mast head vs fractional rigs, altho not as hot as the keel or anchor. Sail cloths seems to also kick up a small storm to a degree too.

At the end of the day, does the boat suit your needs, and how you sail. With options I have today, I would not want a full keel in the salish sea where I sail, as I would never get to sail many days of the year, unless it had a BIG rig on it. When it is under 5-7 knots, one needs a mid 20-1 SA/disp to make the thing move! Not to mention, the thing turns like an aircraft carrier, so for the how I sail, a fin is better than full. If I went offshore, I would still take a fin, altho maybe a bit longer, still a deeper one. Saw a Hunter with a shoal draft the other day in some uper teen winds. he was going nowhere fast, was not pointing as high as the T-bird or US30 that went flying by him! Along with him going sideways more! Then again, race crews are usually better setup than a cruiser. Even after the sails came down, he was not moving with the motor agains everything too fast.

Marty


----------



## GBurton

skygazer said:


> While cleaning my office today to avoid starting taxes, I happened to read the back cover of an old "Practical Sailor" magazine, Sept. 2011.
> 
> Because I've been thinking about fin keels and bulbs, which sound very good, I was immediately struck by the following quote:


This is a good example of why a more "high tech" design is not necessarily the best tool for the job so to speak.

What about how the boat is built? There is a lot to be said for the old overbuilt boats that will take all kinds of abuse.

Don't get me wrong, I'm not against technology and scientific research resulting in a better boat, its just that in a lot of these cases what looks good on paper may not be the best in reality.

In Paulos video example of the open 70 being knocked down by the large wave and returning to the upright position rapidly, the trade off is a very fragile boat. In the first leg 3 of the 6? boats retired before the half way point and 2 of those never made it into the Atlantic....


----------



## PCP

GBurton said:


> ...
> 
> In Paulos video example of the open 70 being knocked down by the large wave and returning to the upright position rapidly, the trade off is a very fragile boat. In the first leg 3 of the 6? boats retired before the half way point and 2 of those never made it into the Atlantic....


You can only be kidding Put your boat sailing at 40K, let him fall repeatedly from the top of 25ft waves at 25k ...and you will probably will have a boat in small pieces. The efforts these boats are subjected are *HUGE*.

Sail one of these boats conservatively at cruising speed (and that means fast anyway) and it will be an incredibly strong boat.

Regards

Paulo


----------



## GBurton

PCP said:


> You can only be kidding Put your boat sailing at 40K, let him fall repeatedly from the top of 25ft waves at 25k ...and you will probably will have a boat in small pieces. The efforts these boats are subjected are *HUGE*.
> 
> Sail one of these boats conservatively at cruising speed (and that means fast anyway) and it will be an incredibly strong boat.
> 
> Regards
> 
> Paulo


That is specious BS there Paulo. These boats are purpose built for ocean racing and the failure rate is unacceptable. On the current leg there are again 3 boats (or is it 4?) with major problems.

Cruising in one of these boats no matter what the speed would be an exercise in self flagellation. To even suggest it is laughable.

Not to mention the COST


----------



## wolfenzee

The anchor rode issue also occurs on fin keels that have a trailing edge that rakes back making it possible for the keel to hook on it.

Yes a full keel with heavy displacement will by it's nature have a better "comfort ratio" , but the whole point of this thread is to discuss the comparative points of fin and full keel. As far as I am concerned for an ocean cruiser the better motion and tracking abilities are extremely important attributes at sea.


----------



## PCP

GBurton said:


> That is specious BS there Paulo. These boats are purpose built for ocean racing and the failure rate is unacceptable. On the current leg there are again 3 boats (or is it 4?) with major problems.
> 
> Cruising in one of these boats no matter what the speed would be an exercise in self flagellation. To even suggest it is laughable.
> 
> Not to mention the COST


I agree that the failure rate has to be reduced and that the next VOR have to be even stronger but my comment had to do with what you said. This:

*"In Paulos video example of the open 70 being knocked down by the large wave and returning to the upright position rapidly, the trade off is a very fragile boat." *

Obviously the trade off for the stability is not a very fragile boat. A boat with that stability characteristics used has a fast cruising boat (and not raced at mad speeds) would be hugely strong.

Most of the motion discomfort on these boats has to do with speed. If you go only at 3 times the speed of your boat the comfort would be completely different.

There are many Ocean cruising boats designed along the lines of Open 60 boats (more beamy boats), some are even luxury boats and I don't see in what that is laughable. The hull lines of a VOR would in my opinion be less adequate for cruising because they provide more speed but a boat more difficult to control and needing a bigger crew...but I would not be surprised if some rich guy commissioned one and I bet the next Wally will have some characteristics taken from these boats, particularly the larger transom and the lateral chine.

Regards

Paulo


----------



## GBurton

PCP said:


> I agree that the failure rate has to be reduced and that the next VOR have to be even stronger but my comment had to do with what you said. This:
> 
> *"In Paulos video example of the open 70 being knocked down by the large wave and returning to the upright position rapidly, the trade off is a very fragile boat." *
> 
> Obviously the trade off for the stability is not a very fragile boat. A boat with that stability characteristics used has a fast cruising boat (and not raced at mad speeds) would be hugely strong.
> 
> Regards
> 
> Paulo


But highly impractical. And uncomfortable. And expensive. And complex (The rigging, canting keel, hydraulics etc etc etc)

Not a good comparison


----------



## casey1999

I like this keel / rudder design:
Pelagic Expeditions Fleet Overview
http://www.pelagic.co.uk/fleet_pel.asp


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## PCP

casey1999 said:


> I like this keel / rudder design:
> Pelagic Expeditions Fleet Overview
> Pelagic Expeditions Fleet Overview


That is not very different than Phillipe Poupon boat. That is what the French call a centerboarder and it is their most common choice in what regards a voyage boat (aluminum centerboarder). However Poupon boat centerboard is a lot more deep and I believe will give the boat a better tracking upwind.

http://www.fleuraustrale.fr/plan-du-bateau.html
Fleur Australe - Fleur Australe FR











That is also the type of boat Jimmy Cornnel recommends as a voyage boat (and that's some recommendation).

I have already referred the very good dynamic stability of those boats that in bad weather pull the centerboard up (for not tripping on the keel) and can dissipate the energy of a breaking wave moving sideways or rotating on a vertical axis.

Regards

Paulo


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## casey1999

Nice footage, wish I could remeber my french from high school a little better...
Regards


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## skygazer

PCP said:


> That is also the type of boat Jimmy Cornnel recommends as a voyage boat (and that's some recommendation).
> 
> I have already referred the very good dynamic stability of those boats that in bad weather pull the centerboard up (for not tripping on the keel) and can dissipate the energy of a breaking wave moving sideways or rotating on a vertical axis.
> 
> Regards
> 
> Paulo


Very, very nice Paulo, I truly enjoyed both videos. In the second one, I really liked the swimming Polar Bear and the Bald Eagles landing and hanging around like crows!

The ice formations, the desolate lands, the whale's tails, absolutely beautiful.


----------



## casey1999

PCP said:


> That's about it I know of guys that have crossed the Atlantic on Beach cats, or sailed the Horn...and they were not crazy but great sailors and were doing something that carried a limited risk. If I tried that it would be madness. I don't have the knowledge neither the skills to do that on a beach cat. However a cruising cat is not properly a beach cat. Here you have a Lagoon 440 sailing with winds in excess of 40K:
> 
> 
> 
> 
> 
> 
> The guy is very good or a bit crazy because he carries too much sail for a relaxed sailing. With a bit less sail he would not be doing 18K but would go at 14K in a much safer way.
> 
> Regards
> 
> Paulo


Paulo,
I sail a mono hull (but have a lot of experience on Prindle 16 beach cat). With a mono with too much sail you heel and maybe get knocked down. In a beach cat you capsize or pitch pole. But what happens with a big cruising cat? Here in HI there have been several tourist fatalities on comercial day sail cats when the standing rigging failed and the mast killed a passanger. The Coast Guard actually made more inspections required.

Another dismasting prompts new alert

How do you know on a cruising cat you have too much sail up? There is really no feed back (like you get on a mono hull) that the wind is loading up your rig. 
Regards


----------



## mitiempo

Paulo

How about a fast boat that is less extreme - like a Cigale?


----------



## PCP

mitiempo said:


> Paulo
> 
> How about a fast boat that is less extreme - like a Cigale?


Less extreme than what?

The Cigale is an aluminum bluewater long distance voyage boat clearly designed taking advantage from the knowledge learned with Open solo boats. It was a precursor and its first "edition" is more than 25 years old. The fact that the boat is still very modern shows the huge success of that design regarding its use and sailor's satisfaction with the performance as a voyage boat and the sailors that have them are not properly marina sailors

The boat is designed to be forgiving, easily sailed solo, to be fast to be strong, to have a large autonomy and to provide a great interior for living aboard. Regarding the aluminium centerboarders it has the disadvantage of having a considerable draft and not be able to go to any place neither to look for shelter more nearer the shore but has the advantage of speed and sailing pleasure.

In the end it is like voyaging on a Porsche cayenne or in a Panamera. Take your pick

There is a member that has one and he could not be more satisfied. Of course, I would prefer the Panamera but I can understand that for most the Cayenne is a more adapted solution.


----------



## PCP

casey1999 said:


> Paulo,
> I sail a mono hull (but have a lot of experience on Prindle 16 beach cat). With a mono with too much sail you heel and maybe get knocked down. In a beach cat you capsize or pitch pole. But what happens with a big cruising cat? Here in HI there have been several tourist fatalities on comercial day sail cats when the standing rigging failed and the mast killed a passanger. The Coast Guard actually made more inspections required.
> ....
> How do you know on a cruising cat you have too much sail up? There is really no feed back (like you get on a mono hull) that the wind is loading up your rig.
> Regards


I am not a cat sailor but I know enough to know that a well design cruising cat can be a very seaworthy boat. Look at the huge number that have circumnavigated without any problem and you will see that is a very populat boat among long rage sailors and for a good reason.

Cats are very different from monohulls, its wider beam and almost no submersed keel gives them a much bigger static stability and a much better dynamic stability. A big cat is almost impossible to capsize by waves alone.

However as you say a cat can be capsized by wind (if it has the sails up) while a offshore monohull can't.

Because of those two characteristics you don't sail a cat in bad weather or high winds the same way you do in a monohull. Cruising cats have already a small rig (compared with its RM) but in bad weather you have to take in consideration that the boat will not come back from a capsize and that means that they should be sailed with more care and in a very conservative way.

Regarding not being able to notice that the boat is near the limit I am sure you can feel that. Look at the beginning of that movie and even without being there you will notice that the boat movements indicates that the boat is near the limit (that's why I have said that the guy or was a very experienced sailor in cats or was a bit crazy).

I have been following capsizing accidents with cats and they happen almost all if not all in a single condition: Incredible strong gusting wind with sailors that are too optimistic about the conditions. Saying that it is obvious that a cat demands a more experienced sailor than a monohull in what regards sailing in bad weather, but with a floating anchor and no sails, a cruising cat has much less changes to be capsized than a similar weight monohull.

I hope it helps

Regards

Paulo


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## mitiempo

Paulo

The Cigale is less extreme than an open boat and has more amenities than a Pogo. I'd take one any day.


----------



## PCP

mitiempo said:


> Paulo
> 
> The Cigale is less extreme than an open boat and has more amenities than a Pogo. I'd take one any day.


Regarding the cruising Pogo it is a much bigger boat. We will see when they finish the first Pogo 50. That one has a much better interior, doors and all

Regarding boat sailing characteristics they are not much different, they have the same kind of hull even if the Pogo has a bit more beam, but the weight is not much different considering that the Cigale 16 is 2 ft bigger.

The Pogo 50 weights 8900kg and the cigale 16 10750kg. The Pogo has more sail but not much: 150m2 for 141m2.

All in all you are right, the Pogo is faster and more close to an open boat...but not much

The Cigale has the advantage of the stronger aluminium hull but the Pogo has an huge advantage in what regards the cruising grounds and capacity to get shelter near the coast. Its draft with the keel up is only 1.5m. With the keel down the tracking upwind should be great with a 3.5m draft keel.

Saying that I would also prefer the Cigale, but that is just because I am getting old But hei, give me a Pogo 50 and I will be happy too.

Regards

Paulo


----------



## Somekindofaviking

DO we really need keel's at all???
Just joking. But..
Have anyone seen this???

CHARTER BOAT LOSES KEEL: And No One Noticed


----------



## mitiempo

Yes, i saw that a while ago. It says a lot for form stability.

But no, keels aren't required.


----------



## Somekindofaviking

Makes me think that those "dreaded bendytoys" can't be so bad at all...
Of curse I would not want to loose the keel. (If it was there to begin with)
But it is kind of reassuring to know, that others have done it without sinking their boat...
Maybe it was just luck, or some kind of production error..
But..... 
Seriously...
Boats, that can handle this kind of abuse...
Should be able to cross some big oceans...






For those of you that are a little allergic to German, press mute...
(No.. I am not from Germany..) 
But..
I am one of those willing to loose some comfort, to gain some speed..


----------



## Ilenart

Yesterday I finally got around to reading this post (guess I was wondering how you could talk about this subject for more than 200 posts, now I know )

Anyway here is my two cents worth. For five years I owned a full length keel Roberts 45 Classic. Below is the design.



Two year ago I sold he Roberts and brought a fin keeled UFO 34, as per below:



I have compared the two yachts extensively in a wide range of wind and sea conditions, including tacking angles, upwind / downwind / reaching performance, effect of waves, etc using the same navigation software / GPS setup.

As would be expected, the UFO 34 certainly had better upwind performance. However the truth is the UFO 34 has better sailing performance in ALL conditions, be it upwind, downwind reaching whatever. I've yet to find conditions where the UFO 34 does not perform better than the Roberts 45.

Some people will probably suggest that this is an unfair comparison comparing a heavy cruising ketch with a medium cruiser / racer. However you also need to remember that the Roberts 45 is more than 10ft longer than the UFO 34 and the larger yacht still loses in a sailing competition. (note 45ft excluded the bowsprit and davits, overall length was closer to 55ft.)

I would also agree with others that point out that the keel type is one of a number of factors that go into sailing ability. However most full length keel boats also tend to be heavy boats with similar charateristics to the Roberts.

Like others have said, there is a reason why Hallberg Rassy, Malo and other builders have progressed from full length to fin keels, as the benefits outweigh the negatives.

Ilenart


----------



## casey1999

Ilenart said:


> Yesterday I finally got around to reading this post (guess I was wondering how you could talk about this subject for more than 200 posts, now I know )
> 
> Anyway here is my two cents worth. For five years I owned a full length keel Roberts 45 Classic. Below is the design.
> 
> 
> 
> Two year ago I sold he Roberts and brought a fin keeled UFO 34, as per below:
> 
> 
> 
> I have compared the two yachts extensively in a wide range of wind and sea conditions, including tacking angles, upwind / downwind / reaching performance, effect of waves, etc using the same navigation software / GPS setup.
> 
> As would be expected, the UFO 34 certainly had better upwind performance. However the truth is the UFO 34 has better sailing performance in ALL conditions, be it upwind, downwind reaching whatever. I've yet to find conditions where the UFO 34 does not perform better than the Roberts 45.
> 
> Some people will probably suggest that this is an unfair comparison comparing a heavy cruising ketch with a medium cruiser / racer. However you also need to remember that the Roberts 45 is more than 10ft longer than the UFO 34 and the larger yacht still loses in a sailing competition. (note 45ft excluded the bowsprit and davits, overall length was closer to 55ft.)
> 
> I would also agree with others that point out that the keel type is one of a number of factors that go into sailing ability. However most full length keel boats also tend to be heavy boats with similar charateristics to the Roberts.
> 
> Like others have said, there is a reason why Hallberg Rassy, Malo and other builders have progressed from full length to fin keels, as the benefits outweigh the negatives.
> 
> Ilenart


Why did you trade to a smaller boat? How do the cruising speeds compare under sail?
Regards


----------



## blt2ski

Casey,

Suggest you look at the RED highlighted part Ilenart's post near the bottom, he answers the Where the smaller lighter boat is better and worst than the larger heavier boat. OR, should I tell you that the larger heavier boat does NOT perform better in ANY condition vs the smaller one!

Marty



Ilenart said:


> Yesterday I finally got around to reading this post (guess I was wondering how you could talk about this subject for more than 200 posts, now I know )
> 
> Anyway here is my two cents worth. For five years I owned a full length keel Roberts 45 Classic. Below is the design.
> 
> 
> 
> Two year ago I sold he Roberts and brought a fin keeled UFO 34, as per below:
> 
> 
> 
> I have compared the two yachts extensively in a wide range of wind and sea conditions, including tacking angles, upwind / downwind / reaching performance, effect of waves, etc using the same navigation software / GPS setup.
> 
> As would be expected, the UFO 34 certainly had better upwind performance. However the truth is the UFO 34 has better sailing performance in ALL conditions, be it upwind, downwind reaching whatever. I've yet to find conditions where the UFO 34 does not perform better than the Roberts 45.
> 
> Some people will probably suggest that this is an unfair comparison comparing a heavy cruising ketch with a medium cruiser / racer. However you also need to remember that the Roberts 45 is more than 10ft longer than the UFO 34 and the larger yacht still loses in a sailing competition. (note 45ft excluded the bowsprit and davits, overall length was closer to 55ft.)
> 
> I would also agree with others that point out that the keel type is one of a number of factors that go into sailing ability. However most full length keel boats also tend to be heavy boats with similar charateristics to the Roberts.
> 
> Like others have said, there is a reason why Hallberg Rassy, Malo and other builders have progressed from full length to fin keels, as the benefits outweigh the negatives.
> 
> Ilenart


----------



## casey1999

blt2ski said:


> Casey,
> 
> Suggest you look at the RED highlighted part Ilenart's post near the bottom, he answers the Where the smaller lighter boat is better and worst than the larger heavier boat. OR, should I tell you that the larger heavier boat does NOT perform better in ANY condition vs the smaller one!
> 
> Marty


I was looking for the cruising speeds in Knots for each vessel.... Seeing one should have a higher hull speed the comparisons would be interesting...

In any case, glad to hear Ilenart likes his ufo 34 as my boat is nearly identical....


----------



## blt2ski

Okay, got it!

The actual speed numbers would be interesting. BUT, probably also like my comparison to some smaller and about the same disp earlier, it may not be as drastic, but still better due to typically a lot more SA/disp ratio on typical fin keels vs full keels.

Marty


----------



## casey1999

blt2ski said:


> Okay, got it!
> 
> The actual speed numbers would be interesting. BUT, probably also like my comparison to some smaller and about the same disp earlier, it may not be as drastic, but still better due to typically a lot more SA/disp ratio on typical fin keels vs full keels.
> 
> Marty


well maybe this is part of answer- this says cruising 6.5 knots:
1998 Roberts 45 Sail Boat For Sale - www.yachtworld.com

My boat does about that with its worn out sail, cruising gear and a non-race skipper to boot. Think I'll stick with my 34, lot cheaper too.


----------



## blt2ski

Thats a whopping 1 knot faster than my 28' on deck boat usually does. I can motor at 6 using a smallish amount of fuel, hull speed is 6.6 knots. I've had it up to 11 surfing down a wave in some upper 30 to low 40 knot winds with a main and 110 up. That was a hoot. Downwind it is not uncommon in low to mid 20 knot winds to be in the 7-9 knot range. 

A local with a Jeanneau SO49iP has had his doing 15-20 with his then 105lb 14 yr old daughter at the helm using an AS up with 20' seas heading to Oz. it was simple driving from what I under stand.

Not sure frankly one really needs a full keel per say, as making sure that ones boat is strong enough scantly wise to handle what one will put it thru. Where as right not, IMHO the VOR 70 bunch, have probably pushed the lightly built scantlings if you will for the rig/hulls etc a bit much, hence why so many have broken things. Where as if you take the same design, build it a bit heavier and stronger, it will not go as fast, but would take some of the beating at a slightly less speed better. now whether or not a couple cruising would want to be going 20+ knots in ALL conditions.......that leaves something to be disCUSSed, as most would probably be happy if they could easily sail in the mid to upper teen range with a 70 boat by them selves. Heck, I'd be happy with a 40-50' boat doing that here and there!

marty


----------



## Ilenart

casey1999 said:


> Why did you trade to a smaller boat? How do the cruising speeds compare under sail?
> Regards


Hi Casey,

I'm doing alot more singlehanding nowdays as the family have grown up and defintely not into sailing. I'm possibly doing a Bali / Indonesia trip in the future, so I needed a yacht that has very good windward performance as you are looking at over 1,000NM of mostly upwind sailing for the return leg. Plus Amadeus has already done the trip, a previous owner competed in a Fremantle to Lombok race about 10 years ago.

Cruising speeds for the two yachts are fairly similar; upwind the Roberts averaged 4.5kts in 12-20kt winds whilst the UFO 34 averages 5kts in 8-13 knot winds. Reaching both yachts averaged around 6kts in roughly 20 kt breezes. These figures are all in the ocean / open waters with a fair bit of wave action.

However the big difference is in pointing and winds below 10 knots. The UFO 34 points an average 10 degrees closer to the wind, which makes an enormous difference to actual miles achieved. With the Roberts with winds below 10 knots the boatspeed would drop below 4 knots and you would have to motor. However with the UFO 34 below 10 knots of windspeed the yacht will maintain at least half of this as boat speed, ie you would still be doing 5 knots going upwind. Reaching or broadreaching you can do even better.

Note that none of the sails of either boats would be called "racing" condition and I'm not really into trying to squeeze the last knot of boatspeed (ie I can't remember the last time I adjusted the backstay). I'm sure others could obtain better numbers with a better suite of sails and more diligent boat handling.

Ilenart


----------



## Ilenart

casey1999 said:


> I was looking for the cruising speeds in Knots for each vessel.... Seeing one should have a higher hull speed the comparisons would be interesting...
> 
> In any case, glad to hear Ilenart likes his ufo 34 as my boat is nearly identical....


Yep, S&S34's are very similar to UFO 34's. There is a S&S34 sitting next to my yacht and apart from the windows its hard to tell them apart sometimes. You can see the SS34 in my photo, yacht with the blue hull.

Roberts 45 hull speed is 7.6 knots whilst the UFO 34 is 7.1 knots. However the UFO gets a lot closer to the theoretical boatspeed than the Roberts 45. I remember Jeff_H saying something very similar in a few of his posts.

Ilenart


----------



## casey1999

Ilenart said:


> Yep, S&S34's are very similar to UFO 34's. There is a S&S34 sitting next to my yacht and apart from the windows its hard to tell them apart sometimes. You can see the SS34 in my photo, yacht with the blue hull.
> 
> Roberts 45 hull speed is 7.6 knots whilst the UFO 34 is 7.1 knots. However the UFO gets a lot closer to the theoretical boatspeed than the Roberts 45. I remember Jeff_H saying something very similar in a few of his posts.
> 
> Ilenart


There is a little wood plaque still in the cabin of my boat. Says "1980 Fremantle to Bali" My boat was born and spent early years in Fremantle.
Regards


----------



## wolfenzee

casey1999 said:


> well maybe this is part of answer- this says cruising 6.5 knots:
> 1998 Roberts 45 Sail Boat For Sale - www.yachtworld.com
> 
> My boat does about that with its worn out sail, cruising gear and a non-race skipper to boot. Think I'll stick with my 34, lot cheaper too.


My 30' full keel ocean cruiser also cruises at 6.5 knots ("hull speed" 6.75 knots, 7 knots under power)with its worn out sail, cruising gear and a non-race skipper to boot.


----------



## Lou452

Well men if you wish to know what a newbee is getting from this thread is that Full or Fin is a matter of choice. The Full might seem to be a little more steady or need less trim under way for a longer time period. It has less draft. The Fin may go better in very light wind and turn just a little faster. Both are as safe and capable as the crew on board. 30 pages or so and this is what I take so far. I do not know what happend to the newbee that started this thread but I am still here sail on ! Thanks for the insight! regards LOU


----------



## PCP

Lou452 said:


> Well men if you wish to know what a newbee is getting from this thread is that Full or Fin is a matter of choice. The Full might seem to be a little more steady or need less trim under way for a longer time period. It has less draft. The Fin may go better in very light wind and turn just a little faster. Both are as safe and capable as the crew on board. 30 pages or so and this is what I take so far. I do not know what happend to the newbee that started this thread but I am still here sail on ! Thanks for the insight! regards LOU


If you join to that between a well designed fin keel and a well deign full keel, the fin keel will point better, it will go much faster downwind (it can go over hull sped quite easily), it will be considerably less expensive (new, of course) and that the full keel will be less prone to suffer damage in a hard grounding, you have got it

Regards

Paulo


----------



## utchuckd

Lou452 said:


> I do not know what happend to the newbee that started this thread but I am still here sail on ! Thanks for the insight! regards LOU


I'm still here! Just keepin my head down and learning.


----------



## blt2ski

utchuckd said:


> I'm still here! Just keepin my head down and learning.


Kewl he is still here......now where is my toy nuec?.....ahhhhhhhhhh........

INCOMING!


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## Daily Alice

I am a bit shy to make my first post, though reading this and many other threads for some time, I would like your consideration. Now I am planning a voyage from Hawaii to Japan (my home), and I will purchase a boat in Hon. or NA West Coast, of 34' or under, due to budget.

My question concerns heavy weather. It has been mentioned that fin keels do not heave to. Comments? Also mentioned was that this could be ameliorated with a drogue (like Jordan series)? For the solo or short-handed skipper, in a smaller boat, would the ability of the boat to heave to be a) crucial, b) important, or c) solved by other means? 

Of course I would love some recommendations of a used boat suitable to the task for < $25K prior to outfitting. There are not so many choices, right? But would you advise me to ignore any/all fin keels in whatever combination? There is a real appeal in making a speedy passage -- in fact I am wanting to deliver the boat (to myself) in Japan, where it will enjoy its future life, with coastal and offshore work. I am not a circumnavigator, or live-aboard person. 

As for sailing experience, offshore experience is limited. I crew on a 37' Jeanneau Sun Odyssey sailing in the Japan Sea, in Southern Kyushu. I do like the idea of weathering battened down in my cabin, reading a book, if it comes to that (or just hanging on).

Last, just to mention, some sort of fin+skeg rudder combination appeals to me (particularly for later coastal use), but I would not want to be foolish. Would you? If you can't heave to with a smaller fin keeled boat, can it be recommended for my (or trans-Pacific offshore) use?


----------



## Ilenart

Hi DA, welcome to Sailnet. As your post is fairly general in future you may wish to start your own thread. 

On heaving to, fin keels can be more difficult to setup compared to long keel yachts, however it really depends on the vessel. Some people suggest using a sea anchor to assist yachts that do not heave too easily. The Book "Storm Tactics" by Lin & Larry Pardey gives a good description of the options and process. I would suggest this issue is somewhere beween "important" / to "solve by other means", ie a Jorden series drogue is an alternative. 

However based on your post, I would suggest that obtaining further experience is probably more desirable, ie crew on someone else's yacht first. This is a lot cheaper and there are always yachts looking for crew. I'm about to fly to the South Pacific to spend six weeks crewing on a yacht. During these trips you can work out for yourself what sort of yacht appeals to you.

Good luck, Ilenart


----------



## Daily Alice

Thank you Ilenart, for the welcome. I am a bit mystified by your seeming "shrug"? My post is quite on the topic under purview, which has to do with the merits of fin vs. full keels, or am I mistaken. That you have responded in part "somewhere between "important"..." would seem to confirm this. Obviously I do not have your experience. I asked a pertinent question because I am seeking expertise. By the way I am also a reader. I have read in the last month various books concerning the 1979 Fastnet tragedy, and have Coles' "Heavy Weather Sailing" by the crook of my arm. I presented a real-world situation, which I am facing. I doubt I will be able to acquire further experience than I am already involved in. But do please move on, everyone, if my newbie post is passé.


----------



## blt2ski

Alice,

Depending upon cost, the SO37 that you are currently sailing on HAS crossed many an ocean. In fact one year it had more of these models doing the ARC than any other model. Granted the atlantic can at times be less of an issue than the pacific.....but that is another issue all together. 

There is usually 3-6+ for sale on the west coast of the NA from Scal up into the BC area at any one times. Other models that might work from Jeanneau are the SO 34.2, 36.2, 37.x and larger models that are with int he last 15 yrs or so. The sunshine 36/38 has also crossed many an ocean too. 

Reality is, many of the more recent boats can and do cross oceans. A fellow on here took an Ericson from the LA or SF area to Australia. I know of a person with a J37c that went from Seattle where I am down to Mexico a couple of yr ago, still down that way. 

At the end of the day, get as much sailing experience on the so37 you are sailing in as many wind conditions as you can, including the day you really do not want to go out, ie too windy in you mind, as you may get caught out in the ocean in worst conditions.

Good luck on choice
Marty


----------



## Lou452

Utchucktd GOOD THREAD best so far !


----------



## Daily Alice

Does everyone agree with Lou452 (post 287) : “Well men if you wish to know what a newbee is getting from this thread is that Full or Fin is a matter of choice. The Full might seem to be a little more steady or need less trim under way for a longer time period. It has less draft. The Fin may go better in very light wind and turn just a little faster. Both are as safe and capable as the crew on board.”

“Both are as safe and capable …” Agreed or not? I am wondering the same thing as the OP, regarding fin vs. full keel. I am concerned in particular with potential heavy weather trans-oceanic (Pacific) sailing, regarding keels. 

It was suggested earlier that boats of equal displacement should be compared, rather than boats of equal length; it was also suggested that “the biggest difference between fin and full keel boats is that fin keel boats are much lighter, that is the point...to compare boats of the same size and different weights is a more accurate comparison… a typical weight fin of the same size as a typical weight full is about half.” (post 254)

Pragmatically, I would compare by cost (which would include adapting/outfitting an older boat for the stated purpose). What type of boat should I spend my money on, commit to, for my intended purpose (Marty, I’m not focused on a Jeaneau - thanks for your information though). At a given price range there are various keel options available. My length limit of roughly 34’ feet relates to cost/performance, among other factors, including potential physical requirements. I don’t suppose there is a clear answer, but I do wonder about heavy weather sailing in “smaller” boats (representing the largest number of solo/hhort-handed circumnavigators, it seems).


----------



## mitiempo

Assuming good build quality and equipment I agree that "Both are as safe and capable as the crew on board."

In light airs the fin should be able to sail well with light sails - the heavy full keel boat not so much. The heavier the boat the larger the sails and the heavier the gear on deck as well, as the loads are higher.

There are a great many fin keel boats out there crossing oceans- probably a lot more than full keel boats - at this time. I am not advocating an extreme fin - but a moderate one. 

My comment about comparing equal weight boats makes sense if you are building new mostly as boats price by the pound more or less. I would much sooner have a 40' fin keel boat than a 30' full keel boat that weighs the same.


----------



## PCP

As it was said by Marty and Ilenart is not so much about the boat but about your skills. As It was said by everybody first you should get a lot of experience before doing a voyage like that. While you get that experience you will sail different kinds of boats, their cost and can have an idea of what kind of boat you prefer or can afford. 

I also don’t understand why you talk about a 34ft related to budget. First you have to have a budget and then find the boat that fits your budget.

As others have said you should open a thread about your specific problem, related with your budget, best places to learn sailing and so on.

As it was said repeatedly on this thread, seaworthiness has not to do with a boat having a fin or full keel, however if your budget is really small you can be restricted to buying a really old boat and the chances are that one would be a full keel.

Open a thread about that, lots of guys have experience about old inexpensive boats that with some work and money can be made seaworthy again.

Regards

Paulo


----------



## wolfenzee

The main purpose of the fin keeled cruising boat, sometimes called a "racer/cruiser" is to emulate the high performance of the racing boats. As with everything in boats there a comprimises...as you approach the performance of a racer, more work is nessesary to handle the boat and the more uncomfortable the boat becomes in nasty weather. The "classic bluewater boat" is a heavy displacement full keel, they are easy to handle, comfortable in nasty weather, though are not super high performance. As with the fin as you approach the extremes of the design both the advantages as well as the disadvantages increase. In the case of my boat it is not a big fat ocean cruiser that can't get out of it's own way in a calm, she is fast in all winds and easy motion in nasty....but likes to heel *alot* and has a narrow beam with a tight cabin...I am happy with her.


----------



## mitiempo

wolfenzee

I am glad you have found a boat that you are happy with.

I think your boat is a classic ocean cruiser of 75 years ago, narrow, and not spacious.

I think boats like the one shown below are considered by many to be a more fitting "classic" ocean cruiser that has the comfort attributes of the past, more room, more speed, and easy handling. Not extreme in design and not mired in the past.


----------



## wolfenzee

My boat was designed to be a no frills/utilitarian single handed ocean cruiser. The rig was tweeked, winches added and I have totally redesigned the interior to be more efficient and pleasing to the eye. The secound owner (who has skippered 100'+ schooners)
had rhis boat for 15 years and called her "A good sea boat".


----------



## mitiempo

wolfenzee

I an not suggesting that your boat isn't efficient, pleasing to the eye, or a good sea boat. You are pleased and that is what counts.

I am suggesting that most do not want a boat from another era, that isn't roomy, and is similar to the Hiscock`s Wanderer III - a great boat from another time.


----------



## wolfenzee

In a thread discussing the merits of the new wide boats vs the older narrow ones...my response was "I chose grace over space".
A friend of mine has A Catalina 30....for a live aboard it wins over mine hands down...but aside from the advantages of my boat at sea, a plastic production boat just isn't my style. A boat, especially if it is your home, is a very personal thing and you should get what you are most comfortable with...remember the only person you need to impress is yourself.


----------



## GBurton

mitiempo said:


> wolfenzee
> 
> I an not suggesting that your boat isn't efficient, pleasing to the eye, or a good sea boat. You are pleased and that is what counts.
> 
> I am suggesting that most do not want a boat from another era, that isn't roomy, and is similar to the Hiscock`s Wanderer III - a great boat from another time.


What boat do you own Brian?


----------



## mitiempo

I currently have a CS27, pictured at the top of my posts.


----------



## wolfenzee

Unlike the wander III that my boat has a huge cockpit and lazarette...so big that raising the quarter deck a little to biuld an aft cabin (which extends under the cockpit) is a viable possibility.


----------



## GBurton

mitiempo said:


> wolfenzee
> 
> I an not suggesting that your boat isn't efficient, pleasing to the eye, or a good sea boat. You are pleased and that is what counts.
> 
> I am suggesting that *most do not want a boat from another era*, that isn't roomy, and is similar to the Hiscock`s Wanderer III - a great boat from another time.


Are you sure about that? Your boats design is probably 30 or 40 years old and there are obviously things about it that you like. It probably has less interior space than wolfenzee's boat as well.


----------



## mitiempo

A CS27 is not the ideal ocean cruiser for a family, or even a couple. But it will do what I want as a singlehander and it is roomy enough.

My ideal boat? Lottery win required.

A 50' version of Dashew's Sundeer in aluminum, or a Boreal 44 or 50 

The Alubat Cigale is a great boat but the keel is too deep for many places.

More affordably I think Perry's Saga 43 would make a great ocean cruiser, as would the Saga 35 for less money.

None are considered wide boats, and the Sundeer type is very narrow.


----------



## wolfenzee

My boat was designed 75 years ago and at that time it was a "tried and true" design.


----------



## PCP

wolfenzee said:


> The main purpose of the fin keeled cruising boat, sometimes called a "racer/cruiser" is to emulate the high performance of the racing boats.......


You can only be jocking. Halberg Hassy, Oyster, Malo, Najad, Hinckley, Morris, all well know cruiser-racers trying to emulate racing boats!!!!

My God, that is really too much Wolf

As I have said, most of them were once full keelers, or medium keelers. They are now fin kellers to sail better not to race or to emulate racers. They are all bluewater cruisers and that's what they were built to do: Bluewater cruising, not to race or even cruiser-racing.

I think everybody can agree with that, I mean cruiser-racers?!!!!



wolfenzee said:


> ... The "classic bluewater boat" is a heavy displacement full keel....


Finally something I can agree with you. Yes in what regards Classic boats you are right.

However modern bluewater boats are fin keelers and that is a fact. Why the hell there is not a market for modern full keel bluewater boats if they are better than fin keel boats for bluewater work? Do you really believe that all the boat designers all the sailors that buy those bluewater boats are wrong and you are right? All of them?

Nothing wrong in liking to sail or own classic or traditional boats (I love both) but from there to pretending that the advantages of a better designed sailboat ended 75 years ago goes a big distance

Regards

Paulo


----------



## GBurton

PCP said:


> You can only be jocking. Halberg Hassy, Oyster, Malo, Najad, Hinckley, Morris, *all well know cruiser-racers trying to emulate racing boats!!!!*
> 
> My God, that is really too much Wolf
> 
> As I have said, most of them were once full keelers, or medium keelers. They are now fin kellers to sail better not to race or to emulate racers. They are all bluewater cruisers and that's what they were built to do: Bluewater cruising, not to race or even cruiser-racing.
> 
> I think everybody can agree with that, I mean cruiser-racers?!!!!
> 
> Finally something I can agree with you. Yes in what regards Classic boats you are right.
> 
> However modern bluewater boats are fin keelers and that is a fact. Why the hell there is not a market for modern full keel bluewater boats if they are better than fin keel boats for bluewater work? Do you really believe that all the boat designers all the sailors that buy those bluewater boats are wrong and you are right? All of them?
> 
> Nothing wrong in liking to sail or own classic or traditional boats (I love both) but from there to pretending that the advantages of a better designed sailboat ended 75 years ago goes a big distance
> 
> Regards
> 
> Paulo


Actually, I think Wolfenzee is correct. You are proof of this Paulo, pushing boats that you call cruising boats but are nothing more than a skimming dish with sails.

Its a specious argument at best.

In the end the older boats such as my Westsail 32 make for comfortable, safe and affordable voyaging boats. 
And don't forget, when you load the skimming dish up with supplies and tools for cruising the sailing characteristics will become less than desirable, sometimes making for a slow, uncomfortable cruise.

Paulo would never admit that of course.


----------



## casey1999

Daily Alice said:


> I am a bit shy to make my first post, though reading this and many other threads for some time, I would like your consideration. Now I am planning a voyage from Hawaii to Japan (my home), and I will purchase a boat in Hon. or NA West Coast, of 34' or under, due to budget.


I would try to stay away from buying a boat in Hawaii if you can (unless you find the perfect boat in perfect condition). Not too many good deals in Hawaii (not many boats for sale) and if your boat needs work, it is very expensive. Even doing the work yourself you are looking at $70 per day dry storage while you work (there are not any options as no marinas have a place to put your boat while you work on it).


----------



## PCP

GBurton said:


> Actually, I think Wolfenzee is correct. You are proof of this Paulo, pushing boats that you call cruising boats but are nothing more than a skimming dish with sails...In the end the older boats such as my Westsail 32 make for comfortable, safe and affordable voyaging boats.
> And don't forget, when you load the skimming dish up with supplies and tools for cruising the sailing characteristics will become less than desirable, sometimes making for a slow, uncomfortable cruise.


I was talking about *Halberg Hassy, Oyster, Malo, Najad, Hinckley, Morris *(all fin sailing boats) I guess that you are calling them: "*skimming dish with sails*".

All uncomfortable boats not able to carry a decent load nor safe boats. 

Do you really believe that?

Regards

Paulo


----------



## GBurton

PCP said:


> I was talking about *Halberg Hassy, Oyster, Malo, Najad, Hinckley, Morris *(all fin sailing boats) I guess that you are calling them: "*skimming dish with sails*".
> 
> All uncomfortable boats not able to carry a decent load nor safe boats.
> 
> Do you really believe that?
> 
> Regards
> 
> Paulo


I was referring to the other 3000 boats you have listed in days gone by...and I think we both know that.


----------



## wolfenzee

The marketing industry has a huge impact on the decisions made by people when it comes to gear as well as boats...if people were to make decisions based on thier own experience, the knowledge of others as well as what just plain suited them best, what people choose would be far different. But our ecomony is based on decisions made by the marketing industry...just look a what people buy across the board and where peoples material priorities lay.
My boat isn't the latest greatest fanciest high tech...as a matter of fact she has alot of stuff most people have never heard of they are so "obsolete"...most of the stuff on the boat was found on boats when she was lauched 40 years ago (and alot of that wasn't so different from when the boat was designed 75 years ago...just logical upgrades). On thing I picked up from my father was to think things through, I spent 30 years looking at other peoples good ideas and bad ideas before I found what suited me best..then I proceeded to customize her to make my boat just what I want.


----------



## PCP

wolfenzee said:


> ......just look a what people buy across the board and where peoples material priorities lay.


Yes, sailors buy the boats that they want to buy, no doubt about that and most of them buy the best their money can afford. Only some lucky ones buy just what they really want (I am not one of them).

But I don't agree that most sailors don't know what kind of boat they want neither that their choice is not adequate to their life style, sailing taste, cruising grounds and of course limited by the boundaries of their budget, at least for most.

Regards

Paulo


----------



## blt2ski

Reality is, as I have said before, the proper Keel of a given boat, on a proper scantling built boat for the purpose etc, is the way to go. 

As also mentioned, we ALL hopefully buy a boat to use base on our needs. Yeah I could have bought a full keel boat for the same cost as my mid 80s Jeanneau. Reality is, I would NOT be happy here in pugetsound with a full keel boat! A fin keel for me is the way to go for how I sail, about 70% racing, 30% cruising or daysailing. With winds down in the less than 10knots a lot, works well. I would imagine if the full keelers I compared my boat too earlier, could get into the 24-1 SA disp ratio, they too "might" be fun in the lighter winds. If not, not as much so. You also get the takes 20 knots to get something moving from boats like the two I compared too, As they are in the 12 or 15-1 range with 6000 lbs of boat. Granted in 30 knots of wind, I have a double reef in, with a 110 , they are still sailing barely with a full main and 110....but compare teh SA/disp of the three, they are about the same!

Not sure the other two would also sail into their slip in less than 5 knots of wind with a main alon at 1-15 knots of boat speed. 40-45 knots of wind, 4-6' seas, no issue for my boat either. Can not remember how mine is vs a westsnail 32 I was on in the mid 70s in the sound with 40-50 knot winds. both do fine. The Westsnail was double reefed with a staysail up. Plowed along in the 4-6' waves too. 

Reality is, one needs a boat for their own needs. Some like paulo and I, will take a fin. Others have spoken about prefering a fin even those that go across oceans etc. If I were to head across an ocean today, it would not be a full keel. MOre than likely a fin, maybe a moderate. Probably not. The new HR looks like a sweet sailing machine, as do the Hanse's etc. 

With that, we should all agree to disagree!

Marty


----------



## GBurton

blt2ski said:


> Reality is, as I have said before, the proper Keel of a given boat, on a proper scantling built boat for the purpose etc, is the way to go.
> 
> As also mentioned, we ALL hopefully buy a boat to use base on our needs. Yeah I could have bought a full keel boat for the same cost as my mid 80s Jeanneau. Reality is, I would NOT be happy here in pugetsound with a full keel boat! A fin keel for me is the way to go for how I sail, about 70% racing, 30% cruising or daysailing. With winds down in the less than 10knots a lot, works well. I would imagine if the full keelers I compared my boat too earlier, could get into the 24-1 SA disp ratio, they too "might" be fun in the lighter winds. If not, not as much so. You also get the takes 20 knots to get something moving from boats like the two I compared too, As they are in the 12 or 15-1 range with 6000 lbs of boat. Granted in 30 knots of wind, I have a double reef in, with a 110 , they are still sailing barely with a full main and 110....but compare teh SA/disp of the three, they are about the same!
> 
> Not sure the other two would also sail into their slip in less than 5 knots of wind with a main alon at 1-15 knots of boat speed. 40-45 knots of wind, 4-6' seas, no issue for my boat either. Can not remember how mine is vs a westsnail 32 I was on in the mid 70s in the sound with 40-50 knot winds. both do fine. The Westsnail was double reefed with a staysail up. Plowed along in the 4-6' waves too.
> 
> Reality is, one needs a boat for their own needs. Some like paulo and I, will take a fin. Others have spoken about prefering a fin even those that go across oceans etc. If I were to head across an ocean today, it would not be a full keel. MOre than likely a fin, maybe a moderate. Probably not. The new HR looks like a sweet sailing machine, as do the Hanse's etc.
> 
> With that, we should all agree to disagree!
> 
> Marty


Yes, lets agree to disagree... without calling each others boats derogatory names. Some cannot manage to do this unfortunately.


----------



## casey1999

wolfenzee said:


> The marketing industry has a huge impact on the decisions made by people when it comes to gear as well as boats...if people were to make decisions based on thier own experience, the knowledge of others as well as what just plain suited them best, what people choose would be far different. But our ecomony is based on decisions made by the marketing industry...just look a what people buy across the board and where peoples material priorities lay.
> My boat isn't the latest greatest fanciest high tech...as a matter of fact she has alot of stuff most people have never heard of they are so "obsolete"...most of the stuff on the boat was found on boats when she was lauched 40 years ago (and alot of that wasn't so different from when the boat was designed 75 years ago...just logical upgrades). On thing I picked up from my father was to think things through, I spent 30 years looking at other peoples good ideas and bad ideas before I found what suited me best..then I proceeded to customize her to make my boat just what I want.


Wolfenzee, 
You have some good points. Do you have some pics of your boat- it sounds interesting.
Regards


----------



## casey1999

GBurton said:


> Yes, lets agree to disagree... without calling each others boats derogatory names. Some cannot manage to do this unfortunately.


Yes, I think we should all agree any boat floating in the middle of the ocean is a good boat, no matter what the keel...
Regards


----------



## wolfenzee

casey1999 said:


> Wolfenzee,
> You have some good points. Do you have some pics of your boat- it sounds interesting.
> Regards


Atkin & Co. - Captain Cicero


----------



## mitiempo

Pretty similar to the Cape George boats. http://www.capegeorgecutters.com/


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## casey1999

wolfenzee said:


> Atkin & Co. - Captain Cicero


It looks like the rig has an inner forestay with backstays, do you have this? If so, how are the backstays tensioned- looks like they deflect the backstay to apply more tension?
Thanks


----------



## windswept too

I'm really enjoying the discussion here and I was wondering if someone with the requisit knowledge can speak to the S&S designed Yankee Dolphin and the Dolphin S&S designed Dolphin with fin keel for the Austrailian market. Keels aside the vessels are identical, blue water capable and trailerable.

It is my understanding based on the wonderful Dolphin websight that both are exceptional cruisers but it's hard to say which is the better perfoming vessel. I would be inclined to think that the Aussie version is but then again the US version was campaigned successfully for many years in the MORC which may explain the benefits of the centerboard in the full keel design.


----------



## wolfenzee

casey1999 said:


> It looks like the rig has an inner forestay with backstays, do you have this? If so, how are the backstays tensioned- looks like they deflect the backstay to apply more tension?
> Thanks


The rig originally had no fixed back stay, just running backstays (18' foot w/ 38' luff...now 15' foot with 37' luff) and no cap shrouds or spreaders, just lower and intermediate shrouds. A self-tending working jib flew on the head stay with a jib top-sail on the topstay...fixed back stay, cap shrouds w /spreaders were added and head stay was made detachable to be able to fly a larger jib on the top-stay...I went one step further and put a pad-eye between the windlass and mooring bit so the head stay could be attached parrelell to the top stay...making it a cutter rig ( distance from stem to mast is 47% of the length of the boat so this was possible).


----------



## casey1999

windswept too said:


> I'm really enjoying the discussion here and I was wondering if someone with the requisit knowledge can speak to the S&S designed Yankee Dolphin and the Dolphin S&S designed Dolphin with fin keel for the Austrailian market. Keels aside the vessels are identical, blue water capable and trailerable.
> 
> It is my understanding based on the wonderful Dolphin websight that both are exceptional cruisers but it's hard to say which is the better perfoming vessel. I would be inclined to think that the Aussie version is but then again the US version was campaigned successfully for many years in the MORC which may explain the benefits of the centerboard in the full keel design.


I had never heard of the Dolphin until you bring it up. Interesting boat. I have the S&S 34 (looks just like the Dolphin except longer). It is interesting that S&S designed the S&S 34 that was also marketed as a Tartan 34, but the boats are totally different (interesting the Tartan 34 also had a centerboard option).
Regards


----------



## BryceGTX

PCP said:


> It is really incredible that someone can believe that from 1800 to today nothing as been learned in what regards sailing boats , stability and particularly dynamic stability.
> 
> Paulo


LOL.. you have to appreciate that most of the mathematics defining fluid dynamics, inertia, moments, static stability and dynamic stability was developed prior to 1900..

What has changed in the last 30 years is the application of microcomputers to perform the same calculations yacht designers performed by hand over 100 years ago.

So yes, there is no doubt in my mind they knew what they were doing back then.

Here is a picture that shows a 1880 design boat. After this picture was recorded, the text says "Mr Bentall then reduced the thickness of the keel, and placed an equivalent weight on it, as a bulb."

This boat has everthing you think is modern:
1) Chopped off bow,
2) Fin keel
3) Bulb
4) Light weight: 50 ft at 10 tons.


----------



## BryceGTX

PCP said:


> One of the most trusted bluewater boats are the Halberg-Rassy. Back in 1982 they did not use a full keel anymore and their 42ft had 3.78m beam.
> 
> Today its new boat, the smaller 415 has 4.11m of beam and use a modern bulbed fin keel.
> 
> And this is not an isolated case but the norm in what refers to modern bluewater cruising boats. Sure, you can find narrower boats still made today but almost in all cases are old designs that are still produced today and that don't reflect the state of the Art neither the actual knowledge in hydrodynamics and boat design.
> 
> Happily there are very few like you, I mean that believe that know more than the best boat designers on the market, otherwise bluewater brands like Najad, Malo, HR, Moody or Oyster would still be making the same type of boats they have made 30 or 40 years ago
> 
> Regards
> 
> Paulo


You are posting as if everything is better with the new design. So what caused Halberg-Rassy to change their design? And in what ways is the new design better? You have not addressed either of these issues.

No doubt the earlier design is better in rough water. However, most sailors, myself included want a faster boat at the expense of rough water capability. So clearly, the benefit of the new design is it is faster and has more room.

There is a tradeoff between comfort and speed. If you want the ultimate comfort in rough water, buy an Island Packet. At the opposite end of the spectrum are the lightweight cruisers Beneteau and Jenneau. The only thing more rough is a racing boat.

So you are agreeing with me I take it.


----------



## BryceGTX

mitiempo said:


> As far as design changes over many decades, I think there are many more boats designed today that are designed to sail well in different conditions without being tweaked and distorted to meet a racing rule. There were certainly many distortions during the IOR rule years but remember many popular long keel cruisers were designed to a rule as well - a better rule but a rule that defined design type all the same. Most of the long keel designs that are popular now for offshore use were designed to race under the CCA rule - Albergs being a good example. Many of them were not intended by their designers to be sailed offshore either.


This is so very true.. it has been going on for more like 200 years though.

It is quite interesting to read the history of sailboat design to see the huge impact racing rules had on boat design.


----------



## BryceGTX

gburton said:


> paulo, did you ever consider that marketing might have something to do with the new designs?
> Many people like you believe everything the manufacturers tell you that you should believe.


bingo..


----------



## BryceGTX

GBurton said:


> That is specious BS there Paulo. These boats are purpose built for ocean racing and the failure rate is unacceptable. On the current leg there are again 3 boats (or is it 4?) with major problems.
> 
> Cruising in one of these boats no matter what the speed would be an exercise in self flagellation. To even suggest it is laughable.
> 
> Not to mention the COST


Very true.. racing boats are not rough water boats.. end of story.. I can't imagine anyone thinking so.


----------



## BryceGTX

wolfenzee said:


> Yes a full keel with heavy displacement will by it's nature have a better "comfort ratio" , but the whole point of this thread is to discuss the comparative points of fin and full keel. As far as I am concerned for an ocean cruiser the better motion and tracking abilities are extremely important attributes at sea.


Very true, yes.. thank you..


----------



## BryceGTX

PCP said:


> Obviously the trade off for the stability is not a very fragile boat. A boat with that stability characteristics used has a fast cruising boat (and not raced at mad speeds) would be hugely strong.
> 
> Most of the motion discomfort on these boats has to do with speed. If you go only at 3 times the speed of your boat the comfort would be completely different.
> 
> Paulo


Absolutely not.. hull design has everything to do with rough water capability..

AS a mater of fact, the racing boat is much better off at a higher speed in rough water to take advantage of its hull... Same as a power boat..
Bryce


----------



## BryceGTX

Daily Alice said:


> I am a bit shy to make my first post, though reading this and many other threads for some time, I would like your consideration. Now I am planning a voyage from Hawaii to Japan (my home), and I will purchase a boat in Hon. or NA West Coast, of 34' or under, due to budget.
> 
> My question concerns heavy weather. It has been mentioned that fin keels do not heave to. Comments? Also mentioned was that this could be ameliorated with a drogue (like Jordan series)? For the solo or short-handed skipper, in a smaller boat, would the ability of the boat to heave to be a) crucial, b) important, or c) solved by other means?
> 
> Of course I would love some recommendations of a used boat suitable to the task for < $25K prior to outfitting. There are not so many choices, right? But would you advise me to ignore any/all fin keels in whatever combination? There is a real appeal in making a speedy passage -- in fact I am wanting to deliver the boat (to myself) in Japan, where it will enjoy its future life, with coastal and offshore work. I am not a circumnavigator, or live-aboard person.
> 
> As for sailing experience, offshore experience is limited. I crew on a 37' Jeanneau Sun Odyssey sailing in the Japan Sea, in Southern Kyushu. I do like the idea of weathering battened down in my cabin, reading a book, if it comes to that (or just hanging on).
> 
> Last, just to mention, some sort of fin+skeg rudder combination appeals to me (particularly for later coastal use), but I would not want to be foolish. Would you? If you can't heave to with a smaller fin keeled boat, can it be recommended for my (or trans-Pacific offshore) use?


I think in general, the full keel is a much better boat for comfort in rough water. Basically, the more mass righting moment versus hull righting you have the more comfortable the boat. The full keel boat invariably has more keel mass. And has a hull with less hull righting moment. For me, the key number is the ratio of mass righting moment to hull righting moment. For lightweight cruisers and racers, this number is nearly zero. For heavy keel cruisers like the Island Packet, this number is closer to one.

For me, my boat is closer to probably about 0.3 or 0.4. It is a relatively wide beam for speed with a huge keel mass for a significant bit of mass righting moment. It is a trade off. It is not a lightweight cruiser, but it is not a heavy weight like an IP.

It is not so much that you can't take a lightweight crusier in rough water.. because it has been done. However, you need a different strategy in rough water than a full keel boat. Where a full keel boat will be more stable, remain more vertical, the lightweight cruiser will follow the waves on beam. So the way I see it, a better strategy is to keep going or be on a drouge in really rough water.
Bryce


----------



## BryceGTX

wolfenzee said:


> The main purpose of the fin keeled cruising boat, sometimes called a "racer/cruiser" is to emulate the high performance of the racing boats. As with everything in boats there a comprimises...as you approach the performance of a racer, more work is nessesary to handle the boat and the more uncomfortable the boat becomes in nasty weather. The "classic bluewater boat" is a heavy displacement full keel, they are easy to handle, comfortable in nasty weather, though are not super high performance. As with the fin as you approach the extremes of the design both the advantages as well as the disadvantages increase.


Very well put..


----------



## mitiempo

This is an interesting discussion, but why in the last few pages has the Island Packet become a benchmark for heavy displacement? There are a great many heavy boats I admire that sail well, but Island Packet? They are certainly heavy but have also bowed to the "cram in a lot of accommodation" theory.


----------



## Daily Alice

casey1999, thanks for your information. Yes it would be a matter of good luck, really (I do have a place to stay in Honolulu, which matters). I am considering CA also.

On the full/fin question, I wonder if Paul Lutus (at the point, year two in his circumnavigation, 1988-90, likely deemed capable) voyaging in a 31' PS Mariah is correct in his observations, such as:

(Midway from Hilo to the Marquesas, March 29, Day 7, 12.d N/149.d W): "It just occurred to me that this passage would be unbearable in anything but a full-keel heavy boat like this one. It's bad enough listening to the bashing the bow is taking, and having one rail in the water about a quarter of the time. I can hardly imagine what it would feel like in a fast, lightweight boat with a fin keel. No wonder cruising sailors discourage use of this route" (p. 43)

(Tahiti to Darwin, Day 5, June 23): "The crossing has been very enjoyable so far. The wind has been favorable, speeds high, and I get to talk to my friends every day. We are comparing positions as we go. "Take Two" is a modern lightweight German-built racing boat with a longer waterline than mine, but they haven't been able to catch up -- mostly because their boat becomes too uncomfortable during high speeds and rough conditions. So to avoid seasickness they reduce their speed" (p. 69)

Could someone suggest a fin keel boat of the same approximate length (31'), which would not suffer as Lutus suggests in the conditions he reports? I realize the descriptions are not that specific, some imagination or speculation is required. Does Lutus raise some practical and relevant matters? His observations echo some of those in recent posts, above.

PS His book, "Confessions of a Long-Distance sailor" is available for free here. Worthwhile, IMHO.



casey1999 said:


> I would try to stay away from buying a boat in Hawaii if you can (unless you find the perfect boat in perfect condition). Not too many good deals in Hawaii (not many boats for sale) ... you are looking at $70 per day dry storage while you work ...


----------



## PCP

BryceGTX said:


> ... Basically, the more mass righting moment versus hull righting you have the more comfortable the boat. ... For me, the key number is the ratio of mass righting moment to hull righting moment. *For lightweight cruisers and racers, this number is nearly zero.* For heavy keel cruisers like the Island Packet, this number is closer to one.
> ....
> Bryce


What do you mean by this: *For lightweight cruisers and racers, this number is nearly zero.* Are you saying that a racer has near 0 of what you call mass righting moment, as opposed to hull righting moment? Can you explain that?

Regards

Paulo


----------



## PCP

Daily Alice said:


> casey1999, thanks for your information. Yes it would be a matter of good luck, really (I do have a place to stay in Honolulu, which matters). I am considering CA also.
> 
> On the full/fin question, I wonder if Paul Lutus (at the point, year two in his circumnavigation, 1988-90, likely deemed capable) voyaging in a 31' PS Mariah is correct in his observations, such as:
> 
> (Midway from Hilo to the Marquesas, March 29, Day 7, 12.d N/149.d W): "It just occurred to me that this passage would be unbearable in anything but a full-keel heavy boat like this one. It's bad enough listening to the bashing the bow is taking, and having one rail in the water about a quarter of the time. I can hardly imagine what it would feel like in a fast, lightweight boat with a fin keel. No wonder cruising sailors discourage use of this route" (p. 43)
> 
> (Tahiti to Darwin, Day 5, June 23): "The crossing has been very enjoyable so far. The wind has been favorable, speeds high, and I get to talk to my friends every day. We are comparing positions as we go. "Take Two" is a modern lightweight German-built racing boat with a longer waterline than mine, but they haven't been able to catch up -- mostly because their boat becomes too uncomfortable during high speeds and rough conditions. So to avoid seasickness they reduce their speed" (p. 69)
> 
> Could someone suggest a fin keel boat of the same approximate length (31'), which would not suffer as Lutus suggests in the conditions he reports? I realize the descriptions are not that specific, some imagination or speculation is required. Does Lutus raise some practical and relevant matters? His observations echo some of those in recent posts, above.
> 
> PS His book, "Confessions of a Long-Distance sailor" is available for free here. Worthwhile, IMHO.


You seem to have learned a lot for someone that says it is very inexperienced and seems also to know what kind of boat you prefer. If you are not a troll and are really inexperienced go out and sail in as many boats as you can and you will find out what is the type that fits you.

The voyage that you say you want to do is not for an inexperienced sailor. Get some really experience first.

Regarding the best type of boat you have to have a budget first. You keep talking about a 31ft. Generally a bigger boat is more seaworthy and also more comfortable, I mean if your budget is not too tight maybe you can avoid some old type of sailing boat that is seaworthy but slow.

Regarding cruising and speed a good way to have an Idea is to go to the ARC page and look through the years for the different type of boats and for their passage times. Full keel heavy boats are always a lot slower than more modern boats and normally there are a relation between the age of the boat and speed (for the same type of boats).

You can also see also that almost anybody is using full keel boats for cruising offshore and unless you consider that they are all inexperienced sailors or masochists you should consider that overwhelming piece of information regarding the type of boat more suited for cruising.

Enjoy the search :
(don't consider corrected time but real time)

http://www.worldcruising.com/content/S634598188535521172/Division Results v120112.pdf

Regards

Paulo


----------



## mitiempo

Daily Alice

Yes, a full keel heavy boat will be more comfortable than a light flat bottom fin keel boat. But not all fin keel boats are flat bottom, there are many moderate displacement fin keel boats, with the rudders usually on skeg and far aft where they are more effective than angled down farther forward at the end of the keel.


----------



## GBurton

Daily Alice said:


> casey1999, thanks for your information. Yes it would be a matter of good luck, really (I do have a place to stay in Honolulu, which matters). I am considering CA also.
> 
> On the full/fin question, I wonder if Paul Lutus (at the point, year two in his circumnavigation, 1988-90, likely deemed capable) voyaging in a 31' PS Mariah is correct in his observations, such as:
> 
> (Midway from Hilo to the Marquesas, March 29, Day 7, 12.d N/149.d W): "It just occurred to me that this passage would be unbearable in anything but a full-keel heavy boat like this one. It's bad enough listening to the bashing the bow is taking, and having one rail in the water about a quarter of the time. I can hardly imagine what it would feel like in a fast, lightweight boat with a fin keel. No wonder cruising sailors discourage use of this route" (p. 43)
> 
> (Tahiti to Darwin, Day 5, June 23): "The crossing has been very enjoyable so far. The wind has been favorable, speeds high, and I get to talk to my friends every day. We are comparing positions as we go. "Take Two" is a modern lightweight German-built racing boat with a longer waterline than mine, but they haven't been able to catch up -- mostly because their boat becomes too uncomfortable during high speeds and rough conditions. So to avoid seasickness they reduce their speed" (p. 69)
> 
> Could someone suggest a fin keel boat of the same approximate length (31'), which would not suffer as Lutus suggests in the conditions he reports? I realize the descriptions are not that specific, some imagination or speculation is required. Does Lutus raise some practical and relevant matters? His observations echo some of those in recent posts, above.
> 
> PS His book, "Confessions of a Long-Distance sailor" is available for free here. Worthwhile, IMHO.


This is exactly what some of us have been trying to say. Thanks for the link and try to cut Paulo some slack, he has drunk the kool-aide that the marketers have presented. Maybe the whole barrel......


----------



## casey1999

I would also think how close the boat can sail to windward should be a consideration for a good cruising boat. What if you are on a lee shore and your engine is dead?


----------



## GBurton

casey1999 said:


> I would also think how close the boat can sail to windward should be a consideration for a good cruising boat. What if you are on a lee shore and your engine is dead?


This is the scenario that is always presented by people that are not knowledgeable about full keel boats. I would like to say that it is a completely unfounded argument as full keel boats do sail to weather. Granted, a few more degrees off the wind than a racer/fin keel boat. I think this is another specious argument created to detract from the virtues of the full keel/modified full keel cruiser.


----------



## casey1999

GBurton said:


> This is the scenario that is always presented by people that are not knowledgeable about full keel boats. I would like to say that it is a completely unfounded argument as full keel boats do sail to weather. Granted, a few more degrees off the wind than a racer/fin keel boat. I think this is another specious argument created to detract from the virtues of the full keel/modified full keel cruiser.


I think you have a good point. An interesting reference:

What's The Ideal Sailing Rig?

I have had the chance to sail on some large wood clippers and square riggers and there is somthing about the solid feel and motion of those ships that would make a long ocean passage very comfortable. I think if funds were unlimited that would be the way to go.


----------



## PCP

GBurton said:


> This is exactly what some of us have been trying to say. Thanks for the link and try to cut Paulo some slack, he has drunk the kool-aide that the marketers have presented. Maybe the whole barrel......


As I have said, sailors buy the boats they want and need and the market provides them and not the other way around. It is like that for cars, houses and a bit in what regards all products.

If the market does not provide full keel boats is because there are no significant number of sailors wanting them. It is as simple as that.

If there was some sailors wanting heavy full keel boats you can be sure there would be someone making, selling them and having a profit.

This is all so obvious that it is difficult to understand why do you believe in a market plot not to sell full keelers. Do you think that all the best boat designers are also part of that plot? None of then are designing full keelers for any kind of sailing, including bluewater sailing!!!

Well, I guess that the conspiracy theories are fashionable now, why not one more?

Regards

Paulo


----------



## casey1999

PCP said:


> As I have said, sailors buy the boats they want and need and the market provides them and not the other way around. It is like that for cars, houses and a bit in what regards all products.
> 
> If the market does not provide full keel boats is because there are no significant number of sailors wanting them. It is as simple as that.
> 
> If there was some sailors wanting heavy full keel boats you can be sure there would be someone making, selling them and having a profit.
> 
> This is all so obvious that it is difficult to understand why do you believe in a market plot not to sell full keelers. Do you think that all the best boat designers are also part of that plot? None of then are designing full keelers for any kind of sailing, including bluewater sailing!!!
> 
> Well, I guess that the conspiracy theories are fashionable now, why not one more?
> 
> Regards
> 
> Paulo


Part of it may be pure economics. For a cruising sailor a full keel may performance wise be best. But from a cost perspective maybe not. To build such a boat it takes a lot more materials (and cost). Maintenace also becomes higher due to heavier weight and more surface area. The boats rig will probably be heavier (more cost) and require more sail area (more cost). So in order to sell more boats to more people need to lower the cost (mass market) and the way to do that is fin keel. Not to say the fin keel does not go faster and points better, but maybe it is not really the best overall design. But in terms of economics, maybe it is the best design. Now maybe you can purchase a good used full keel and then you got a good deal- if you are cruising.

For me with a full keel, I would have a hard time as I do a lot of single handing. I would have a harder time docking a heavier boat and dealing with one that takes more skill to manuver in tight places under both sail and power. But if I were doing some extended ocean passages, maybe full keel would be way to go.

Regards


----------



## casey1999

PCP said:


> As I have said, sailors buy the boats they want and need and the market provides them and not the other way around. It is like that for cars, houses and a bit in what regards all products.
> Regards
> 
> Paulo


At least here in the US, people buy a lot of things we don't need, but the advertisers tell us we do. Here we have a lot of big sport utility vehicles that are daily drivers. We live in McMansions and we buy a lot of things that within a year are broken and end up in a landfill. But the sellers are telling us we need these things.


----------



## GBurton

casey1999 said:


> Part of it may be pure economics. For a cruising sailor a full keel may performance wise be best. But from a cost perspective maybe not. To build such a boat it takes a lot more materials (and cost). Maintenace also becomes higher due to heavier weight and more surface area. The boats rig will probably be heavier (more cost) and require more sail area (more cost). So in order to sell more boats to more people need to lower the cost (mass market) and the way to do that is fin keel. Not to say the fin keel does not go faster and points better, but maybe it is not really the best overall design. But in terms of economics, maybe it is the best design. Now maybe you can purchase a good used full keel and then you got a good deal- if you are cruising.
> 
> For me with a full keel, I would have a hard time as I do a lot of single handing. I would have a harder time docking a heavier boat and dealing with one that takes more skill to manuver in tight places under both sail and power. But if I were doing some extended ocean passages, maybe full keel would be way to go.
> 
> Regards


I think you have hit the nail on the head with your first paragraph.

As regards to single handing a heavy full keeled boat, this is what I do nearly all the time as I like to sail by myself. I'm talking day sailing.

I learnt how to sail on hobie cats and J24's . I decided to buy a Westsail after sailing a J24 quite a bit on San Francisco bay. I cant imagine how it would be on an ocean passage 

Docking takes a bit of forethought, but I actually enjoy the challenge.


----------



## casey1999

Good link:
Keel Types - Full, Deep Fin, Bulb, Wing, Centerboard, Canting - Waves « Jordan Yacht Brokerage


----------



## PCP

casey1999 said:


> Part of it may be pure economics. For a cruising sailor a full keel may performance wise be best. But from a cost perspective maybe not. To build such a boat it takes a lot more materials (and cost). Maintenace also becomes higher due to heavier weight and more surface area. The boats rig will probably be heavier (more cost) and require more sail area (more cost). So in order to sell more boats to more people need to lower the cost (mass market) and the way to do that is fin keel. Not to say the fin keel does not go faster and points better, but maybe it is not really the best overall design. But in terms of economics, maybe it is the best design. Now maybe you can purchase a good used full keel and then you got a good deal- if you are cruising.
> 
> For me with a full keel, I would have a hard time as I do a lot of single handing. I would have a harder time docking a heavier boat and dealing with one that takes more skill to manuver in tight places under both sail and power. But if I were doing some extended ocean passages, maybe full keel would be way to go.
> 
> Regards


Cost could explain why the mass market production boats are not doing full keelers but would not explain why luxury boat builders or custom boats made by NA to clients with an unlimited budget are not full keelers.

As I have explained the Luxury boat builders were doing full keelers 40 years ago and the same manufacturers are doing now fin keel boats. That has nothing to do with price but with providing clients with what they want: better sailing boats.

Regards

Paulo


----------



## Jeff_H

casey1999 said:


> Good link:
> Keel Types - Full, Deep Fin, Bulb, Wing, Centerboard, Canting - Waves « Jordan Yacht Brokerage


That is pretty funny. You have to love the internet. Those are badly editted versions of old articles of mine.


----------



## PCP

very interesting read from one of those luxury builders (Gozzard) that build bluewater boats for ages regarding their keel choice and their evolution from full keel to a modified fin keel:

We have a unique perspective when it comes to keel design (philosophy) by having had many years of practical experience with a full keel, a modified full keel with a "Brewer Bite" and our current configuration; a modified fin keel with fully skeg protected rudder ...

Prior to 1980 all Ted's designs were based on the traditional full keel. By the mid 80's our keels evolved into a modified full keel by employing the Brewer Bit (first designed by Ted Brewer). Essentially it was a full keel design with a large section cut away in front of the rudder. ...

In 1999 we modified the keel again (along with a complete redress of the hull structure). This time we further decreased the wetted surface and used a real 64 Series NACA foil section. The new keel was a little shorter (fore and aft), taller and far more defined. Still too large to be called a fin keel but at the same time it could not really be called a modified full keel either.

*The results were very positive. The biggest improvement is in performance without any noticeable loss of sea keeping ability. In fact the new design is easier to control, lighter on the helm and obviously faster in all points of sail.*

Why do we like a Modified Fin over a Full or a true Fin Keel?

A typical fin keel used on your average club racer/cruiser has a significant performance advantage over your typical full keel - of this there is no question. A fin keel sails far better (especially to weather) and affords superior maneuverability both under sail and power (especially in reverse).

There is also no question that full keels have some advantages over a narrow fin and they include better tracking (especially in quartering seas), being obviously more durable structurally by simply having far more contact area with the bottom of the hull and allowing lower CG (center of gravity) storage capacity (which would make the boat more stable).

*For the modern cruiser concerned with safety and comfort, obviously the requirements should more closely favor the full keel characteristics at the expense of the higher performance fin... right? Well, not so fast ... .*

Full keel designs have very limited directional stability in reverse as they have a tendency to either go straight or walk in the direction of the prop rotation.

They will not steer in reverse unless you have enough speed over the rudder to counter the massive lateral plain of the keel. This means you have to have water flow (and a good deal of it) over the rudder before you will gain any ability to control direction... this often means you are going way too fast for the situation. Any one who tells you any differently is either trying to sell you a full keel boat or has never experienced anything else. ...

For many this fear is real and far worse than getting caught out in any bad storm. You will often find these owners are very reluctant to take their boats into unknown situations which limits their freedom and ability to use the boat.

Full keels do not turn very well... while full keels do have the advantage of a lot of lateral resistance on some points of sail, *they generally sail very poorly to weather. It is not that the boat can't point to weather; it is the fact that the leeway is so bad you will find it is much faster (Velocity Made Good or VMG) to crack off and build speed to allow the keel to work with its lateral surface.*

Unlike a full keel, a fin keel can create lift to offset the leeway (to a degree). It does this by utilizing an airfoil shape similar to that of a jet's wing which is designed to work at high speeds and, as it turns out, water has very similar hydrodynamic properties at low speed to air at high speed. All the various foil sections have been developed and tested and the simple fact is that there is a relationship between the shape of the foil and the length of the cord compared to the width. ... To try and claim a full keel can create lift is misleading at best as any lift it can create is offset negatively (if not completely) by the increased wetted surface of the keel itself.

Wetted Surface - As a vessel passes through the water it physically moves the water around the boat and this creates friction. The more wetted surface the water has contact with, the more effort is required to move the boat. Obviously a full keel has far more wetted surface than a smaller keel.

....










The Gozzard is a very very conservative boat builder and it is not an example of a modern bluewater boat. Brands like Malo, Oyster, Najad, Halberg-rassy Moody, Morris have also done that way, I mean from full keel, to modified full keel, to modified fin keel. The difference is that all these have already passed from a modified fin keel to a fin keel and I guess Gozzard will do that one day, if it does not bankrupt first.

Regards

Paulo


----------



## GBurton

PCP said:


> very interesting read from one of those luxury builders (Gozzard) that build bluewater boats for ages regarding their keel choice and their evolution from full keel to a modified fin keel:
> 
> We have a unique perspective when it comes to keel design (philosophy) by having had many years of practical experience with a full keel, a modified full keel with a "Brewer Bite" and our current configuration; a modified fin keel with fully skeg protected rudder ...
> 
> Prior to 1980 all Ted's designs were based on the traditional full keel. By the mid 80's our keels evolved into a modified full keel by employing the Brewer Bit (first designed by Ted Brewer). Essentially it was a full keel design with a large section cut away in front of the rudder. ...
> 
> In 1999 we modified the keel again (along with a complete redress of the hull structure). This time we further decreased the wetted surface and used a real 64 Series NACA foil section. The new keel was a little shorter (fore and aft), taller and far more defined. Still too large to be called a fin keel but at the same time it could not really be called a modified full keel either.
> 
> *The results were very positive. The biggest improvement is in performance without any noticeable loss of sea keeping ability. In fact the new design is easier to control, lighter on the helm and obviously faster in all points of sail.*
> 
> Why do we like a Modified Fin over a Full or a true Fin Keel?
> 
> A typical fin keel used on your average club racer/cruiser has a significant performance advantage over your typical full keel - of this there is no question. A fin keel sails far better (especially to weather) and affords superior maneuverability both under sail and power (especially in reverse).
> 
> There is also no question that full keels have some advantages over a narrow fin and they include better tracking (especially in quartering seas), being obviously more durable structurally by simply having far more contact area with the bottom of the hull and allowing lower CG (center of gravity) storage capacity (which would make the boat more stable).
> 
> *For the modern cruiser concerned with safety and comfort, obviously the requirements should more closely favor the full keel characteristics at the expense of the higher performance fin... right? Well, not so fast ... .*
> 
> Full keel designs have very limited directional stability in reverse as they have a tendency to either go straight or walk in the direction of the prop rotation.
> 
> They will not steer in reverse unless you have enough speed over the rudder to counter the massive lateral plain of the keel. This means you have to have water flow (and a good deal of it) over the rudder before you will gain any ability to control direction... this often means you are going way too fast for the situation. Any one who tells you any differently is either trying to sell you a full keel boat or has never experienced anything else. ...
> 
> For many this fear is real and far worse than getting caught out in any bad storm. You will often find these owners are very reluctant to take their boats into unknown situations which limits their freedom and ability to use the boat.
> 
> Full keels do not turn very well... while full keels do have the advantage of a lot of lateral resistance on some points of sail, *they generally sail very poorly to weather. It is not that the boat can't point to weather; it is the fact that the leeway is so bad you will find it is much faster (Velocity Made Good or VMG) to crack off and build speed to allow the keel to work with its lateral surface.*
> 
> Unlike a full keel, a fin keel can create lift to offset the leeway (to a degree). It does this by utilizing an airfoil shape similar to that of a jet's wing which is designed to work at high speeds and, as it turns out, water has very similar hydrodynamic properties at low speed to air at high speed. All the various foil sections have been developed and tested and the simple fact is that there is a relationship between the shape of the foil and the length of the cord compared to the width. ... To try and claim a full keel can create lift is misleading at best as any lift it can create is offset negatively (if not completely) by the increased wetted surface of the keel itself.
> 
> Wetted Surface - As a vessel passes through the water it physically moves the water around the boat and this creates friction. The more wetted surface the water has contact with, the more effort is required to move the boat. Obviously a full keel has far more wetted surface than a smaller keel.
> 
> ....
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> The Gozzard is a very very conservative boat builder and it is not an example of a modern bluewater boat. Brands like Malo, Oyster, Najad, Halberg-rassy Moody, Morris have also done that way, I mean from full keel, to modified full keel, to modified fin keel. The difference is that all these have already passed from a modified fin keel to a fin keel and I guess Gozzard will do that one day, if it does not bankrupt first.
> 
> Regards
> 
> Paulo


Nothing new in your argument here Paulo. Except that its funny that the manufacturers first reason of why not to buy a full keel boat is because they don't back up under power well..... and people are more afraid of docking than they are of an offshore storm. Really?

They forgot to mention that the fin keel boat is cheaper to manufacture as well. I wonder why?


----------



## jordanship

Best I could do Jeff. Gotta love the internet, especially all your good posts here.


----------



## Jeff_H

*Full or fin keel and a dozen other marginally related topics*

This thread sure has taken a tortuous track from the original question about the merits of Fin vs Full keels. Coming back to the thread, I find myself thinking; Are you still here?







[/URL][/IMG]

But in its wild path, the thread has opened a whole slew of issues with various folks seemingly talking past each other, rather than having a productive and vaguely linear dialogue on the original topic of keel types.

It seems to me that much of this non-linearity has been caused by the sheer broad range of the topics being used, and the points diffused the loose association between the responsed and the topic being bandied about, and the sometimes dubious assumptions about the implicit connection between these various design factors. To me, in many cases, the connection between many of the indivdual comment and the responses to the point being raised, at best comes off as a real stretch and at worst, comes off as, 'I don't know nothing about art, nor understand your point, but I know what flavor ice cream I like' type non-sequitors. It would seem as if this discussion would be a lot more productive if the topics were treated separated rather being discussed with the assumption that they are a lot more linked than I would respectfully suggest that they are.

To try to help clarify this point, I would suggest that a brief index of the discussion topics contained within this thread might include: 
•	The merits and limitations of fin keels versus full keels. 
•	Boats operating as a system rather than as individual components discussed in abstract
•	How most people who sail use their boats (day sailing and coastal cruising) and what those people need out of their boats, vs. more specialized uses such as offshore-distance cruising, performance passage makers, high level racers, and racer-cruisers. 
•	The impact of marketing vs. science in the selection of a boat by the general boat buying public. 
•	The impact of marketing vs. science in the selection of a boat by the offshore cruising boat buying public. 
•	Why Island Packets are not a good example of either traditional full keeled cruising boats nor of modern design principle, but somehow seem to be able to market themselves as both. 
•	The impact of cost on selection if the goal is one of these specialized uses. 
•	The merits and limitations of boats which are short or long for their displacement. 
•	The merits and limitations of various hull forms, and the impact of modeling on the success of a design of any general type. 
•	The merits of simplicity vs. sophistication vs. targeted sophistication.

I am sure that I am missing other topics that reared their ugly little heads, but it seems to me it would be a lot more useful, if people tried to make thier arguments based on points that were actually being made, and with the topic it was being mentioned in. Instead, it appears that many of the participants respond with an answer that only relates to a completely different topic relative to the point being contested and/or which at best perhaps assumes some association to the point raised.

For example, the thread starts with a very broad general discussion of keel types. The counter to some point in that discussion is an argument that boats that are longer or shorter for their weight make better offshore cruisers. To which the response is that the hull forms popular on coastal cruisers are less comfortable for offshore use. To which, the response is that coastal cruiser hull forms perform better. To which the response is that full fledged, grand prix level race boats are fragile. And so on. It sure makes for a confusing, and less useful thread, that taken at face value is not even all that accurate. But at least it has been mostly been civil&#8230;

Jeff


----------



## Jeff_H

jordanship said:


> Best I could do Jeff. Gotta love the internet, especially all your good posts here.


No problem. Thanks for the kind words. If you would like I would be glad to send you cleaner versions of those discussions electronically. They appeared to have been selected from edited versions and then further edited.


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## PCP

GBurton said:


> Nothing new in your argument here Paulo. Except that its funny that the manufacturers first reason of why not to buy a full keel boat is because they don't back up under power well..... and people are more afraid of docking than they are of an offshore storm. Really?
> 
> They forgot to mention that the fin keel boat is cheaper to manufacture as well. I wonder why?


On Gozzard, after trying both types of keels on basically the same boat they say:

*The biggest improvement is in performance without any noticeable loss of sea keeping ability. In fact the new design is easier to control, lighter on the helm and obviously faster in all points of sail.....*

Full keels do not turn very well... *while full keels do have the advantage of a lot of lateral resistance on some points of sail, they generally sail very poorly to weather. It is not that the boat can't point to weather; it is the fact that the leeway is so bad you will find it is much faster (Velocity Made Good or VMG) to crack off and build speed to allow the keel to work with its lateral surface.*

Directionality backwards it's an advantage but it is not the more important. The more important is that they get a better sailboat without *"any noticeable loss of sea keeping ability"*. That is the reason why all boat manufacturers changed to fin keel, not only Gozzard.

A modified fin keel like the one on the Gozzard is not less expensive than a full keel. Gozzard is an heavy boat, now as before and heavy boats are expensive.

Regards

Paulo


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## casey1999

Jeff H
You have a wealth of knowledge of boats. Could you tell me how you gained this knowledge?
Regards


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## Jeff_H

And for the record since this does relate to the original topic, at least when I was associated with the boat building, a well engineered fin keel boat is actually quite a bit more expensive to build than a full keel. The requirement of a precision ballast casting, more sophisicated framing, the requirer higher strength keel bolts and backing plates all add to the cost of building a fin keel boat. 

Inexpensive boats typically had longer keels with encapsulated non-cast ballast until coastal sailors came to expect more performance out of their boats.


----------



## Jeff_H

*Another topic*



casey1999 said:


> Jeff H
> You have a wealth of knowledge of boats. Could you tell me how you gained this knowledge?
> Regards


Thank you for the kind words. I wrote this for someone else who asked a similar question so I apolize that it is pretty long. Growing up I wanted to be a yacht designer. Like some kids study and memorize batting averages, I studied and memorized boats. I have some training as a yacht designer and have designed and built a few boats, and worked for naval architects and yacht designers at different times in my life, BUT I do not consider myself a professional yacht designer. I have also worked in boat yards and as a consultant to boatyard owners, designing repairs and alterations to yachts. My mother had two companies that built and imported boats from Taiwan, which gave me a lot of insights into the boat building industry. I still attend yacht design symposia in an effort to remain current in yacht design theory.

I first started sailing in 1961 and more or less have sailed ever since. I enjoy most types of sailing. I currently sail on the Chesapeake Bay but have sailed on much of the U.S. Atlantic coast. In a given year, I typically will daysail, race (both my own boat and other people's boats), and cruise (both my own boat and other people's boats) and can be out on the water as many as 100 days a year. I do a lot of single-handing. While I have cruised offshore and made a number of offshore passage, I strongly prefer coastal cruising. While I have raced dinghies and very high performance boats, I prefer racing 22 to 40foot keelboats. I have owned wooden boats and enjoy sailing on traditional watercraft. These days I prefer to own modern performance cruisers.

In a general sense, I have strong preferences for boats that perform well, and that offer a wide range of sailing abilities in a wide range of conditions. I really am no longer a fan of 'heavy weight offshore boats'. I currently own a Farr 38 (Farr 11.6) which I daysail, singlehand and cruise. The Farr 11.6 are hard to classify boats and not exactly your normal off-the-rack cruising boat or racing boat. They were built as fast offshore cruisers but have had a very successful racing record. They also have a remarkable record as short-handed offshore passage makers. For example, my boat was single-handed into the States from Cape Town, South Africa

In my life, I have owned over a dozen boats with family members owning over several dozen more. I typically race on a variety of boats over the course of the year and sometimes help out with deliveries, or help a new owner 'sort out' a boat that is new to them. I also like sailing up to boats from astern and observing their sailing abilities, meaning relative speed, stability and motion. All of that combined gives me a relative sense of how many different boats are built and how they sail. I have also been a consultant to people who are restoring boats or making tricky repairs which has given me the chance to crawl around the back corners of many boats over the years and I have a pretty good memory of the details which I have seen.

Many of my friends are yacht designers, sailmakers, and marine researchers and surveyors who collectively also give me an inside track when I am researching a topic. (I think that Bruce Farr cringes when he sees me coming up the aisles at the grocery store.)

My comments are predominantly based on my own experiences and research. I see my comments as being simply my opinion, but I also see them as reasonably well informed comments based on comparasons of the boats I have known, either through sailing on or repairing, and the information gained by reading, lectures or discussions with design professionals.

Anyway, that is who I am.


----------



## wolfenzee

PCP said:


> On Gozzard, after trying both types of keels on basically the same boat they say:
> 
> *The biggest improvement is in performance without any noticeable loss of sea keeping ability. In fact the new design is easier to control, lighter on the helm and obviously faster in all points of sail.....*
> 
> Full keels do not turn very well... *while full keels do have the advantage of a lot of lateral resistance on some points of sail, they generally sail very poorly to weather. It is not that the boat can't point to weather; it is the fact that the leeway is so bad you will find it is much faster (Velocity Made Good or VMG) to crack off and build speed to allow the keel to work with its lateral surface.*
> 
> Directionality backwards it's an advantage but it is not the more important. The more important is that they get a better sailboat without *"any noticeable loss of sea keeping ability"*. That is the reason why all boat manufacturers changed to fin keel, not only Gozzard.
> 
> A modified fin keel like the one on the Gozzard is not less expensive than a full keel. Gozzard is an heavy boat, now as before and heavy boats are expensive.
> 
> Regards
> 
> Paulo


Full keel boats hat different degrees of fullness ... some are incredibly difficult to turn and some not....mine is not, the deepest part of the keel is at base of the rudder post. I will show a couple of examples from the same designer starting with my boat.


























As you can see "full keel" covers a ver wide spectrum...this is almost as bad as the mono vs multi-hull argument. Both have advantages and dis advatages (which I have mentioned earlier), you need to find the variation the best suit YOU.


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## Jeff_H

To be fair, What appears to be Ben Bow (top) and Wild Duck (bottom) are purely William Atkins design, while Elf (middle) is often ascribed to John Atkins influence.


----------



## PCP

wolfenzee said:


> Full keel boats hat different degrees of fullness ... some are incredibly difficult to turn and some not....mine is not, the deepest part of the keel is at base of the rudder post. I will show a couple of examples from the same designer starting with my boat.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> As you can see "full keel" covers a ver wide spectrum...this is almost as bad as the mono vs multi-hull argument. Both have advantages and dis advatages (which I have mentioned earlier), you need to find the variation the best suit YOU.


Fact is that I love those boats. I was the proud owner of one that was not far away from the last one. I am sure they all sail well, suit cruising needs and are a pleasure to sail but in a kind of classical way.

It is not fair to compare their sailing performance with a modern boat&#8230;.now if we are talking about pleasure that can be a completely different thing.

Last year when I sailed a Salona 41 I saw a lot of others sailors taking pictures at my boat and that brought memories of the days I sailed a traditional boat only that at that time the photos taken where even more.

Regards

Paulo


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## GBurton

Jeff_H said:


> And for the record since this does relate to the original topic, at least when I was associated with the boat building, a well engineered fin keel boat is actually quite a bit more expensive to build than a full keel. The requirement of a precision ballast casting, more sophisicated framing, the requirer higher strength keel bolts and backing plates all add to the cost of building a fin keel boat.
> 
> Inexpensive boats typically had longer keels with encapsulated non-cast ballast until coastal sailors came to expect more performance out of their boats.


You must not have been exposed to many full keel boats. The Westsails at least had 3 different lead castings that were also "precision cast"
The "more sophisticated framing" is a dubious one also as production boats are not custom built. I also note that in one post you said something to the effect of "encapsulated keels are harder to repair than fin keels". I don't think that's true as the fin keel would by nature create a lever effect in a hard grounding, requiring a complete removal, inspection, new bolts etc etc while the full keel would simply have the damage ground out, be allowed to dry and than patched and faired.

Once again it comes down to personal preference, not one design being "better" than the other.


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## Lou452

Yes Jeff still here... I need to hear both sides so I am glad they keep going! This was a thread for a newbee and it is nice to see heavy weights step up. They have been civil


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## wolfenzee

Jeff_H said:


> To be fair, What appears to be Ben Bow (top) and Wild Duck (bottom) are purely William Atkins design, while Elf (middle) is often ascribed to John Atkins influence.


The top one was commisioned by the author E.B.White in 1936 and designed by William Atkin...the boat (original name Kathrinr S. } was never built and it was given the name Captain Cicero and later published in MoToR BoatinG magazine. Being a commision there are a few influences that differ from Akin's other boats. Building plans are still available from Pat Atkin's web page

The Ben Bow http://www.atkinboatplans.com/Sail/BenBow.html is a much heavier displacement/fuller keel than the Captain Cicero Atkin & Co. - Captain Cicero.


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## Jeff_H

Burton, you know better than that, the full keeled boats that I owned included a 1939 Stadel Cutter which I owned for 11 years, and a 1949 Folkboat which I restored. As you may recall I helped a fellow building a kit version of the Westsail 32 which had no precision cast ballast. Just concrete and scrap metal. You might want to go back and read the discussion on merits of a bolt on vs encapsulated keel. It is all about the trade-offs.


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## GBurton

Jeff_H said:


> Burton, you know better than that, the full keeled boats that I owned included a 1939 Stadel Cutter which I owned for 11 years, and a 1949 Folkboat which I restored. As you may recall I helped a fellow building a kit version of the Westsail 32 which had no precision cast ballast. Just concrete and scrap metal. You might want to go back and read the discussion on merits of a bolt on vs encapsulated keel. It is all about the trade-offs.


In the case of a wooden boat, I would think that a fin or a full keel would sustain more damage than a glass boat, but the fin keeled boat would always be more susceptible to damage than a full keeled boat. That is just basic physics.
As far as the Westsail 32 you helped build with concrete and scrap steel, 95% of these boats left the factory with the ballast installed (this is from the general manager of the factory at the time)
Unfortunately you have contributed to building a not so desirable Westsail 32 ..what a shame as the boat is potentially a great cruiser.


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## skygazer

*Re: Another topic*



Jeff_H said:


> Anyway, that is who I am.


Wide experience, yes. . . .

But you left out a couple of things that I notice.

Articulate and civil!

I find that your discussions and insights really raise the level on this site. Thank you.


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## pvajko

*Re: Full or fin keel and a dozen other marginally related topics*

Jeff, glad you are back.



Jeff_H said:


> •	Why Island Packets are not a good example of either traditional full keeled cruising boats nor of modern design principle, but somehow seem to be able to market themselves as both.


I'd love to hear your opinion on this particular one (I mean the first part, not the 'how do they market themselves') because I almost bought one last year but then decided that I don't need a full keel for the Long Island Sound.


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## Jeff_H

Pvajko and Skygazer, Thank you for your kind words of support.



GBurton said:


> In the case of a wooden boat, I would think that a fin or a full keel would sustain more damage than a glass boat, but the fin keeled boat would always be more susceptible to damage than a full keeled boat. That is just basic physics.
> As far as the Westsail 32 you helped build with concrete and scrap steel, 95% of these boats left the factory with the ballast installed (this is from the general manager of the factory at the time)
> Unfortunately you have contributed to building a not so desirable Westsail 32 ..what a shame as the boat is potentially a great cruiser.


Starting from the bottom up, I agree with you entirely about the Westsail 32 with the concrete and scrap metal ballast and specifically said that to the fellow building the boat at the time. I tried to make the case that the Westsail started out with less ballast than the Eric which it was patterned after, so going to a low density ballast made less than zero sense. He claimed that he had sailed on one and talked to "A bunch of guys who were building their Westsail 32's that way, and they sailed fine." I'll take your word that these other not so desirable Westsail 32s were a rarity. But that is another story.

Getting back to the original topic, as you acurately note, due to the physics of the situation either a wooden boat or a glass boat with a fin keel will potentially experience much higher stresses in a grounding than a full keeled boat.

One of the clear advantages of a full keeled boat with external bolt-on ballast is that the ballast takes the initial impact and spreads the load over a much larger area of the boat's structure. Because the ballast is comparatively low aspect, and placed outside of the structure, the forces imparted into the hull and fastenings are predominantly in compression and sheer, which is what conventional boat building techniues can absorb best.

The stresses on a fin keel are higher in part because of the greater lever arm of the keel, but also because of the smaller contact are of the fin limiting area within which the connections need to be made, and so the fastenings work at an inverse mechanical advantage. Not an inherently good thing.

The higher stresses of the fin keel, require much more careful engineering and construction techniques if the same margin of safety is to be achieved. (This was in part why I said that properly engineered fin keeled boats are typically more expensive than a simialr strength full keeled boat.)

But that does make any specific fin keel automatically weaker than any specific full keel. Properly engineered, the fin keel needs to be design to equal or greater safety factors than the full keel design intended for the same purpose. That means designing an internal structure and fastening scheme which can safely withstand the fin keel's greater loads, and distribute them over a large enough area of the boat that damage is not incurred during its service life.

In my mind the problem with discussing this in the abstract, vs analyzing this in the specific, is that for the most part, the majority of fin keel boat whoch have been built have been aimed at the racing, coastal cruising and value oriented communities. These boat have purposely smaller safety factors than boats intended for dedicated offshore passage making and cruising. By the same token, a much larger percentage of full keel boats built in recent years were designed with the intent of offshore use.

So, when this comes down to debating the strength advantage of a specific design feature citing specific boats, it is easy to suggest a range of examples of full keeled offshore cruiser that are way more robust than some collection of fin-keeled coastal cruisers, or more glaringly yet, compare dedicated offshore full-keeled cruisers to the strength of some dedicated race boat. But it gets harder to make the point when the same comparison uses dedicated offshore cruisers with fin keels that in theory have been designed to the same safety factor as any other purpose built offshore cruiser.

The same argument applies in the hull form debate as well. It is easy to say that a purpose built, offshore cruiser- no matter what its keel type, should have a more comfortable motion, more carrying capacity, and a more seaworthy hull form no matter what its size or displacement than would be expected on a dedicated race boat, racer cruiser, coastal cruiser, or even a boat designed to make occasional offshore passages.

Where these debates go off the rails is that comparasons are often made between purpose built offshore cruisers versus purpose built race boats, racer-cruisers, value oriented family cruisers and coastal cruisers and so on, when each may be well suited and optimized for their secific intended use and so do not represent a fair example for comparason on the issue being debated.

Jeff


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## jfitzgerald

Having sailed both, I recall loving the full keel when I had to heave to and hating it when maneuvering in marinas. Island hopping in the Caribbean, I'd opt for fin keel. Good sailing


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## Alden68

I hope that the posters here take to heart Jeff's message. Its hard to compare apples to apples in this kind of discussion but without it there is little relevance. You can't compare a heavily built boat purposely designed to get caught in a storm to a Catalina 27 and say that the Catalina is a lesser boat because it has a fin keel. That doesn't make any sense. Compare a Panda 40 to a Saga 43. Purpose built ocean cruising boats with different keels. I know which one I prefer. 

As a previous owner of a full keeled boat designed and built in the 60's I can say that I would rather quit sailing altogether than bob around in that scow again. We put a man on he moon in the sixties but my boat might as well have been the mayflower. Albeit she was a thing of beauty.


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## souljour2000

....As a previous owner of a full keeled boat designed and built in the 60's I can say that I would rather quit sailing altogether than bob around in that scow again. We put a man on he moon in the sixties but my boat might as well have been the mayflower. Albeit she was a thing of beauty......



.....yeah, but I'll ask...what kind of sailing do you do now...vs.. back then?
I don't like marinas....and keep me boat on a hook...manouevering a full-keel in a marina situation would be a nightmare I'd rather skip...but the old narrow ones ride well at a mooring...and even better on the high seas...and I get me exercise rowing me dinghy out to her mooring..whoever (she) is over the last few years...A full keel gives me a good feeling if ever aground too..but if we all wanted full keels...or vice versda..world of sailing would be more boring place...


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## Daily Alice

*Re: Full or fin keel? Quotes from Robert Perry*

Robert Perry's, "Yacht Design According to Perry" (2008, pp. 118-122) has a short chapter, titled "Full Keels" which complements the descriptions above. Expositions are lucid and reader-friendly. And a firm point of view, aligned to an extent with Paulo's, and contradicting some (see points on "stability" and "tracking") -- a position which supports an evolution away from the full/modified-full keel toward at minimum, a hybrid keel, properly and creatively designed and engineered (a provocative topic in itself).

Here are some extracts:

"A full or modified full keel has several disadvantages, one of which is that it lacks the aspect ratio to develop good flow across the chord for lift. In order to achieve an appropriate thickness ratio on a long-chord keel, you have to make it excessively thick, which gives too much added displacement and frontal area. If you reduce the thickness ratio to achieve acceptable displacement and frontal area, the keel may become too thin to keep flow attached and will stall at early angles of attack. Stalling eliminates the keel's lift and causes drag. The good news is that when a full keel stalls and loses life, you're still left with all that planform area to prevent the boat from being shoved sideways. I use a 7 to 9 percent foil thickness ratio for my modified full-keel designs."

"&#8230; wetted surface has a severe negative effect on boat speed in light air, therefore an effort should be made to reduce wetted surface. From my perspective though, the biggest disadvantage of a full or modified full keel is the additional displacement it adds to the canoe body compared with a far less bulky keel. On the other hand there are pragmatic benefits &#8230; "enough internal volume to house the ballast" "room left over for a tank or two" "contributes to a lower VCG" (most of these boats "use cast iron at 450 lbs/cubic foot (or even less dense materials) rather than cast lead at 700 lbs/cubic foot and in doing so fail to take full advantage of their keel volume to lower the VCG. Lead is always better. It's nice to have a big, long keel on which to rest your boat when you haul out. People also say that a full keel [incl. modified full] protects the rudder, but I wonder. Most full-keel boats still have the heel or gudgeon of the rudder at the lowest point, so there is still a chance of damaging the rudder when you hit bottom. I design the rudder bearing or "Gudgeon" to be at least 4" above the lowest part of the keel to help prevent damage.

I do not regard having the propeller in an aperture [in such keels] to be an advantage &#8230; The worst boats to operate in reverse are [such] boats&#8230; Of course you may sail in waters littered with lobster and crab pots, or maybe your boat sits on the mud at low tide. A full keel is also a strong shape to have in a catastrophic grounding or if you are pounding on a beach. Haulouts with crude gear may be easier&#8230;"

"A sailor must balance these virtues against the full keel's performance vices. *To me performance is paramount*. This is not to say that all full/modified full keels are slow. Starting with the Tayana 37, I made an effort to separate the full-keel shape as much as possible from the canoe body by reducing the garboard radius and increasing the span. My Taishiba series boats all sail beautifully, and I'm sure that Chuck Paine's similar full-keel boats do also. Look, for example at the new Cabo Rico 45 &#8230; [possibly] an example of a modified full keel or the very elusive modified fin keel."

"&#8230;given the amount of volume in a full keel, all else being equal, a full-keel boat will be less stable through the normal sailing range, 0 to 30 degrees of heel, than a fin-keel boat. Picture the midsections of a full-keel boat and a fin-keel boat with both boats heeled 20 degrees. The immersed portion of the fin-keel midsection is almost entirely to leeward of the centerline, where it contributes to righting moment via buoyancy. The windward portion of the hull is mostly out of the water, where it, too, contributes to righting moment via gravity. The immersed portion of the full-keel midsection, on the other hand, is still perhaps 40 percent to windward of the centerline, where it contributes to further heeling&#8230; technically expressed, the volume of a full keel reduces the righting arm (the distance from the VCG to the transverse center of buoyancy). Thus, not surprisingly, I get a lot of calls from owners of older full-keel boats complaining about lack of stability."

"The stiffest boats are those with deep, high-aspect fin keels with some type of bulb at the tip. It's all about getting the VCG low&#8230; On the other hand, it's important to remember that bulbs in themselves are not hydrodynamically desirable. A clean fin has far less drag&#8230; A relatively thin, high-aspect fin will have less frontal area than most other keels, which can reduce drag and add up to a downward wind speed advantage, but the thinness comes at a price. [It] poses a structural challenge due to the short chord where the fin attaches to the hull. A short fin makes it difficult or impossible to spread the fin loads over a big section of the hull. You wouldn't want to bounce a fin like that off a reef for a day or two, nor would you want to sit the boat's entire weight upon it when you haul out. Short-chord, high-aspect fins are unsuitable for most cruising boats, which hold durability as a primary desirable feature."

"Remember, more stability means a boat that will stand up to its sail better and present a more efficient keel shape to the water. People like stiff boats&#8230; It's often argued that a full- or modified full-keel boat has better directional stability, which is often referred to as "tracking ability." My experience is just the opposite. I have found that the further I can separate the keel form the rudder, the better a boat tracks&#8230; I'm a believer in the 'feathers on the end of an arrow' theory. In other words, keep the rudder as far aft as possible."

"&#8230; [L]imiting yourself to more 'normal' cruising keels, you arrive at hybrid keels like those in the accompanying illustration. This is an external keel for the 57-foot cruising sled 'Mobisle.'&#8230; I have used this hybrid keel shape on three of my 'cruising sleds.'&#8230; Obviously you want to limit draft on any cruising boat, and this severely ties the hands of the designer."


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## PCP

*Re: Full or fin keel? Quotes from Robert Perry*

Thanks for posting. Interesting and informative read.



Daily Alice said:


> Robert Perry's, "Yacht Design According to Perry" (2008, pp. 118-122) has a short chapter, titled "Full Keels" which complements the descriptions above. .. a position which supports an evolution away from the full/modified-full keel toward at minimum, a hybrid keel, properly and creatively designed and engineered (a provocative topic in itself).
> 
> Here are some extracts:
> 
> "&#8230;given the amount of volume in a full keel, all else being equal, a full-keel boat will be less stable through the normal sailing range, 0 to 30 degrees of heel, than a fin-keel boat. Picture the midsections of a full-keel boat and a fin-keel boat with both boats heeled 20 degrees. The immersed portion of the fin-keel midsection is almost entirely to leeward of the centerline, where it contributes to righting moment via buoyancy. The windward portion of the hull is mostly out of the water, where it, too, contributes to righting moment via gravity. The immersed portion of the full-keel midsection, on the other hand, is still perhaps 40 percent to windward of the centerline, where it contributes to further heeling&#8230; technically expressed, the volume of a full keel reduces the righting arm (the distance from the VCG to the transverse center of buoyancy). *Thus, not surprisingly, I get a lot of calls from owners of older full-keel boats complaining about lack of stability."
> *
> "The stiffest boats are those with deep, high-aspect fin keels with some type of bulb at the tip. It's all about getting the VCG low&#8230; On the other hand, it's important to remember that bulbs in themselves are not hydrodynamically desirable. A clean fin has far less drag&#8230; A relatively thin, high-aspect fin will have less frontal area than most other keels, which can reduce drag and add up to a downward wind speed advantage, but the thinness comes at a price. [It] poses a structural challenge due to the short chord where the fin attaches to the hull. A short fin makes it difficult or impossible to spread the fin loads over a big section of the hull. You wouldn't want to bounce a fin like that off a reef for a day or two, nor would you want to sit the boat's entire weight upon it when you haul out. Short-chord, high-aspect fins are unsuitable for most cruising boats, which hold durability as a primary desirable feature."
> 
> *"Remember, more stability means a boat that will stand up to its sail better and present a more efficient keel shape to the water. People like stiff boats&#8230; It's often argued that a full- or modified full-keel boat has better directional stability, which is often referred to as "tracking ability." My experience is just the opposite. I have found that the further I can separate the keel form the rudder, the better a boat tracks&#8230; I'm a believer in the 'feathers on the end of an arrow' theory. In other words, keep the rudder as far aft as possible."*


Regarding this:

"The stiffest boats are those with deep, high-aspect fin keels with some type of bulb at the tip. It's all about getting the VCG low&#8230; On the other hand, it's important to remember that bulbs in themselves are not hydrodynamically desirable. A clean fin has far less drag&#8230; A relatively thin, high-aspect fin will have less frontal area than most other keels, which can reduce drag and add up to a downward wind speed advantage, but the thinness comes at a price. [It] poses a structural challenge due to the short chord where the fin attaches to the hull. A short fin makes it difficult or impossible to spread the fin loads over a big section of the hull. You wouldn't want to bounce a fin like that off a reef for a day or two, nor would you want to sit the boat's entire weight upon it when you haul out. Short-chord, high-aspect fins are unsuitable for most cruising boats, which hold durability as a primary desirable feature."

Bob Perry, even if he considers very short fins (I call them foil bulbed keels) advantageous in what regards sailing qualities, sees them unfit for cruising boats, based on lack of durability and structural difficulties. Nevertheless they are incresingly used in fast cruising boats.

I agree with what Bob says about the structural challenge to be bigger however many boat builders resolved that with an elegant structural solution: A carbon or steel large frame where the keel is attached and that receives also the loads from the stays. This way all the keel loads are distributed by the hull and the attachment point is incredibly strong. The keel construction has also to be different from the more traditional ones to give more resistance to that thin foil. Several methods are used being the most strong a machined piece of solid steel where the lead bulb is attached.

Of course this has a disadvantage: price but an increasingly number of manufacturers are using the system among them: Salona, Comar (Comet), Grand Soleil, X-Yachts, Luffe, Arcona.

Regards

Paulo


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## wolfenzee

There are certain basic atributes that apply to all full keels and others that apply to all fins (as I have mentioned earlier) each have advantages and disadvantages....but taking the best attributes of the best designed fins and comparing them aganst the worst of the full (which appears to be happening cumulatively) just isn't fair and/or defeats the purpose ofthe thread. A well designed full has these same advantages in performance over a poorly designed fin while keeping the traditional advantages of the full (in all fairness I will point out this works both ways). I pursonally prefer a well designed full...that said in a honesty there a a few fins I would be happy with.


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## Daily Alice

Bryce,

I got as far as finding VMG, metacenter and CB for a boat, but how do you arrive at " the ratio of mass righting moment to hull righting moment"? I mean what do you need first, for data, and what formulas are you using? I ask because your approach seems useful. Isn't hull righting moment graphed over various heel angles (like from 0-30 deg.)? Anyway, I'm curious, thanks.



BryceGTX said:


> ...For me, the key number is the ratio of mass righting moment to hull righting moment. For lightweight cruisers and racers, this number is nearly zero. For heavy keel cruisers like the Island Packet, this number is closer to one. For me, my boat is closer to probably about 0.3 or 0.4. It is a relatively wide beam for speed with a huge keel mass for a significant bit of mass righting moment. It is a trade off. It is not a lightweight cruiser, but it is not a heavy weight like an IP. Bryce


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## Captain milos

I think by asking this question,first you have to ask yourself what type of sailing you are going to do.If you want to cross oceans and want a proven multi functional design chose full keel.
If you are going to hang around the coast chose fin keel


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## souljour2000

Captain milos said:


> I think by asking this question,first you have to ask yourself what type of sailing you are going to do.If you want to cross oceans and want a proven multi functional design chose full keel.
> If you are going to hang around the coast chose fin keel


 I am now just really realizing that I no longer have a boat good for gunkholing . (full-keel Morgan Columbia 40)....could be worse though since she drafts only 4 and a half...

.....but for island-hopping...say... thru the Bahamas and the "thorny" on down which I hope to do someday soon...I am glad to have a train-tracking, full-keeler that can hold a course on a 1-2 or 3 day leg without always having auto-helm turned on...but instead just lashing off the wheel...and I can possibly take 15 minute nap,if single-handed (with multiple set alarms) and hold a course too without autohelm..I have never had an auto-helm/auto-pilot on any of my former boats...so this is new ....and am not familiar with auto-pilots yet...but for now...gimme a full-keeler..or cutaway-forefoot...One day when I'm older  and can afford a marina and need maneuverability...I'm sure I might spring for .5 kt faster fin-keeler


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## PCP

souljour2000 said:


> ...I am glad to have a train-tracking, full-keeler that can hold a course on a 1-2 or 3 day leg without always having auto-helm turned on...but instead just lashing off the wheel...and I can possibly take 15 minute nap,if single-handed (with multiple set alarms) and hold a course too without autohelm.....


Have you keep up with the thread?

Regarding tracking ability Bob Perry said (in one of his books, particularly about boat design):

*"It's often argued that a full- or modified full-keel boat has better directional stability, which is often referred to as "tracking ability." My experience is just the opposite. I have found that the further I can separate the keel form the rudder, the better a boat tracks&#8230; I'm a believer in the 'feathers on the end of an arrow' theory. In other words, keep the rudder as far aft as possible."*

of course there are bad designed fin keelers and bad designed full keelers but implying a broad generalization assuming that full keelers track better than fin keelers just does not make sense. In fact Bob Perry says the opposite, not as a rule but as a tendency.

Regards

Paulo


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## mitiempo

50 years ago virtually everybody sailed a full keel boat - whether daysailing, coastal cruising, or crossing an ocean. They raced them as well.

The last decades have seen many changes to design, some from racing rule influence, some from design knowledge. 

Today more boats with fin keel and aft rudders, either on a skeg or a spade, are crossing oceans than full keel boats. 

As the keels were shortened to reduce wetted surface the forefoot was cut back and the rudder moved forwards, ending up close to mudships in some boats. This doesn't make for a very efficient rudder and added to its location it was usually raked forward at a steep angle.

The aft rudder was the solution. Leaving the keel to be designed as an efficient foil.

I agree with Paulo and the Maestro - the feathers should be on the end of the arrow. 

And as with everything there are both good and not so good designs of either type.


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## keforion

This discussion could be tightened up a bit, I think, if we could get away from vague terms like "Full" vs. "Fin" and focus on the relevant parameter: aspect ratio. This is basically depth divided by chord (length in the direction of water flow) A more formal definition involves area but is just a refinement. 

A "Full keel" boat has a low aspect ratio underwater profile, maybe 0.5 depth to chord, and a "Fin keel" boat has an underwater aspect ratio of at least 1:1, and as high as perhaps 7:1 in the various Open class racers.

The sail plans usually follow these trends, low aspect ratio (think CCA or "America") on full keel hulls and tall rigs on the more racy vessels.

If you look at the L/D curves in C A Marchaj's Theory and Practice of Sailing (best book ever, on the subject, IMHO) you see that there is no question that the high aspect ratio system is best in terms of absolute performance, i.e. getting to windward. (I won' t get into going downwind as damn near anything can do that.)

The L/D ratios at optimal angles of attack are very high for high aspect ratio foils, whether air or hydro, and correspondingly lower for low aspect ratios. This is just simple physics -- the end, which is a leak, is smaller and farther away.

The thing which is important as to this discussion, i.e.which is preferrable, is to be found in examining how the L/D ratio varies with angle of attack. Keep in mind that angle of attack is the angle between the apparant wind vector and the span of the foil. It is determined, hopefully, by how you steer, but also by wind shifts, pitching, rolling, yawing of the vessel, elsticity in the rig and on and on.

The L/D plots for high aspect ratio systems have very high peaks BUT this high performance peak occurs over a very narrow range of angles of attack.

The same plot for a low aspect ratio system shows a broader range where the L/D is not as high as before, but does not change so severely.

So, what's best?

If you love clawing to windward and ekeing out a 1/32 point advantage over a competitor and are willing to stand white-knuckled at the helm to do it then the high aspect ratio, i.e."fin-keel" is the way to go. But bear in mind that if you get out of the groove with either the sail plan or the detached spade rudder, either or both will fall off of that peak in the L/D curve, i.e "stall" and you may well end up ass-over-teakettle with your boat wondering what the hell you were trying to do.

If you'd rather let the boat sail herself for the most part, the broader range of the low aspect ratio is more appropriate. The extreme of this is the old Tahiti ketch with the helm lashed and the skipper sipping rum all the way across the Pacific.

Having said that, there are qualifications:

There are some very nice designs out there which offer a sensible compromise -- but they are all pretty old and therefore not very fashionable. To my mind the epitome of yacht designs of this sort was in the postwar years but before the CCA and subsequent rules began to seriously deform common sense. These boats had tall, but not preposterous rigs, deep but not overly long "full" keels, strongly cut away in the forefoot and after body (aspect ratios around 1:1, thus somewhere in the middle of the current arguement) but blended structurally, and hydrodynamically -- look at the bottom of a C Morgan boat to see what I mean -- also perhaps a bit structurally sounder than the more recent bolt on fins.

I think the unfortunate trend in modern yacht design is that the buying public seems easily beguiled into thinking that the design principles of a Volvo 60, manned by a bunch of professional athletes standing watch on watch and probably terrified nearly every second (but loving it, I am sure) is somehow the right thing for the average guy and his mate, or vice versa, who want to go to sea.

I kind of don't think it is and will offer two observations to support this:

1. Most of these wide beamed, high aspect ratio fin-keeled (with spade rudders) and similar tall thin rigs spend their time as patios.

2. When you do see them sailing they usually do so with an enormous amount of twist in the sail rig -- Harken even advertises windward sheeting mains'l travellers to promote this -- so as to lessen the "twitchiness" of the high aspect rig referred to earlier. With a twisted foil, there is always at least some part of it working properly -- but never all of it. If they could figure out how to make twisty fin keels and twisty spade rudders we'd see fewer "crash jibes," "death broaches" and all the other terms recently invented to describe the behaviour of these things.

Paolo and/or Polux opines that the NAs design and the builders build these sort of vessels because that is what the buying public wants. I suspect that he is right but that the buying public is, as usual, seriously stupid, at least in the short term -- did we really need tail fins on our cars in the 70's?

And I remember a recent (year or so ago -- that's recent to me) in Cruising World where all the Senior Editors chose their own ideal cruising boat. There was not a single modern design in the lot. They were mostly of the type I described above or perhaps a bit later when the "Brewer Bite" became fashionable. None of the types heavily advertised and reviewed in the same pages, ironically.

In the end -- to each his own -- but do some research and have a bit of a clue as to what to expect from the physics of the various design parameters.


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## PCP

keforion said:


> ....
> I think the unfortunate trend in modern yacht design is that the buying public seems easily beguiled into *thinking that the design principles of a Volvo 60, manned by a bunch of professional athletes standing watch on watch and probably terrified nearly every second (but loving it, I am sure) is somehow the right thing for the average guy and his mate, or vice versa, who want to go to sea.*
> 
> I kind of don't think it is and will offer two observations to support this:
> 
> 1. Most of these wide beamed, high aspect ratio fin-keeled (with spade rudders) and similar tall thin rigs spend their time as patios.
> 
> 2. When you do see them sailing they usually do so with an enormous amount of twist in the sail rig -- Harken even advertises windward sheeting mains'l travellers to promote this -- so as to lessen the "twitchiness" of the high aspect rig referred to earlier. With a twisted foil, there is always at least some part of it working properly -- but never all of it. *If they could figure out how to make twisty fin keels and twisty spade rudders we'd see fewer "crash jibes," "death broaches" and all the other terms recently invented to describe the behaviour of these things.*
> 
> ....


The one that know me know that I am a firm believer that each sailor should have a boat adapted to his sailing tastes and not otherwise. The big choice in the boat market, specially on the European one is a clear sign that choice exists. Boatbuilders that make boats that no one wants go bankrupt and out of the market. It is as simple as that.

This thread is not about choice of sailing style but about the means to provide that sailing style. What I have been saying is that even for the ones that like heavy boats (and that are some still made today) a fin keel or a modified fin keel on those boats makes everything a full keel would do, only better.

This is not about the choice of the type of boats (performance cruiser, voyage offshore boat, coastal cruiser, heavy, medium or light sailboat or the type of sailing each one prefers, this is about sail design: the best solutions to attain a mean that is, a given type of sailboat.

Regarding what you say concerning the difficulty of sailing fast performance boats directly derived from racing boats, it seems to me that you are the one that is partial. I do understand and see as natural that others have different sailing options regarding the ones I prefer. It is you that think that for offshore work all the boats should be like the ones you prefer for that kind of sailing.

Just to show how wrong you are about sailing difficulty I will post here what Eric, the happy owner of a brand new Pogo 12.50 (the cruising version of a racing 40class boat), said about its first sail on its boat (I hope he doesn't mind).



EricKLYC said:


> &#8230;..
> 
> Last week we sailed the boat over to Nieuwpoort, which was a cold but nice and very valuable experience. I will be happy to discuss this in more detail later, but the bottom line is: the boat dislikes pointing or sailing dead downwind, keeping up the speed is the issue *and then the VMG is always very correct. It is quite a different way of sailing compared to more traditional designs*.
> 
> I mentioned before the statement of an experienced class 40 sailor: it's just like a big 470 dinghy. I've been sailing a 470 for almost 30 years and could not agree more. "Sail the boat under the mast" and first try to build up the apparent wind. Then you get exhilarating sailing everywhere between a close and a broad reach.&#8230;.
> 
> The initial (form) stability is as spectacular as the 4m50 wide (and honestly quite disgraceful) beam. Even with myself and my two basketball centre players of sons on the same side, the boat hardly moves.
> 
> Under sail, more than 20° of heel only slows the boat down. But before you get there, you have already enjoyed the enormous power of both the hull (form stability) and the 3m deep, leaded keel (weight stability).
> 
> Between l'Aber Wrach (North Brittany) and Cowes we kept all the sail (full main + solent) up in 25 knts on a broad reach. *With nice, long, 3m high waves and gusts up to 35 knts the average speed was around 14 knts with some wonderful long and thrilling surfs up to 21 knts, without ever feeling out of control.*
> 
> *So our first experience after 450 NM with the 12.50 is: WYSIWYG. *
> 
> A big 470 with visually basic, but functional and in fact quite comfortable accommodation for our crew of 6.
> 
> Eric


To make things clear that boat option is not the one I favor to myself, not because it is too radical in what regards sailing but because it has an interior "too clean" for me and because on the type of sailing I do I make a lot of upwind sailing that is not the strong point of that boat. But if I was circumnavigating, following the trade winds you can bet that it would be that the type of boat I would chose&#8230;and I am not implying that would be the right choice for you or any other that prefer slower heavy boats with a different sea motion.

Regards

Paulo


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## keforion

Paulo:

Thanks for the response. But your statement, "It is you that think that for offshore work all the boats should be like the ones you prefer for that kind of sailing," is off the mark. I never try to tell anyone what they should do. Gave that up long ago. I was pointing out the physics implications of the various design choices. 

The post by EricKLYC is interesting. I would note the following:

"... but the bottom line is: the boat dislikes pointing or sailing dead downind."

"... it’s just like a big 470 dinghy."

"... on a broad reach... without ever feeling out of control." Well, I should hope so, given that on this point of sail most would be taking a nap.

This all just confirms my points that these things are "big dinghys." 

I would also observe that almost anyone who goes for a first sail in a brand new boat is ENTHRALLED. 

What I think this discussion needs, and what I tried to provide, is some guidance to the prospective buyer as to what sort of behaviour he or she might expect from a boat by considering some quantifiable and specific parameters of it's design, namely the aspect ratios of its underwater form and sailplan. There are many other design parameters as well, of course, but they are off topic.

What you or I or anyone else prefers is irrelevant. The point is to understand how a boat is likely to behave given these measureable parameters, and whether that is what the prospective thinks he or she might want.

You seem to want to deal in vagueries, opinions and personal attacks. I have little patience for any of that.


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## pvajko

PCP said:


> But if I was circumnavigating, following the trade winds you can bet that it would be that the type of boat I would chose&#8230;


Well, when I was young, I had a 470 and it was really great fun sailing that boat. But you know, if it's really like a big 470, then that is certainly not something for cruising.


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## PCP

keforion said:


> ..
> 
> "... but the bottom line is: the boat dislikes pointing or sailing dead downind."
> 
> "... it's just like a big 470 dinghy."
> 
> "... on a broad reach... without ever feeling out of control." Well, I should hope so, given that on this point of sail most would be taking a nap.
> 
> This all just confirms my points that these things are "big dinghys."


You seem to forget some relevant facts and it is not hard to understand why

Regarding this:

*"... on a broad reach... without ever feeling out of control." * *Well, I should hope so, given that on this point of sail most would be taking a nap.*

You seem to forget that the boat was sailing with full sail, 25K wind, gusting 35K, with 10ft waves, averaging 14K with points at 21K. I find amazing that a cruising sailboat can do that without the skipper felling the slightest loss of control, even more so on the first sail on an unknown boat.

Regarding this:

*"This all just confirms my points that these things are "big dinghys"* you are wrong about that. What Eric is saying is that the boat *SAILS* like a big dinghy not that is a big dinghy. He knows and I know that his boat has an outstanding final stability with a great AVS. A dinghy has not that and relies on the weight of the sailor not to capsize and when capsized at 90º it will not re-right itself without the help of the sailor's weight. It is not a big dinghy, IT SAILS LIKE A BIG DINGHY.

Regarding this:

*"... but the bottom line is: the boat dislikes pointing or sailing dead downind."*

You seem to forget what he wanted to say, or maybe you did not understood. He said:

*"the boat dislikes pointing or sailing dead downwind, keeping up the speed is the issue and then the VMG is always very correct. It is quite a different way of sailing compared to more traditional designs".*

He knows and I know that his boat is faster against the wind, VMG, than most modern performance cruisers, not to mention any heavy old keeler. What he is saying is that the way to sail the boat against the wind is different: the boat goes faster (VMG) if a bit out of the wind (compared with another performance boat, maybe at the same angle as a full keel boat) because it makes much more speed that way and in the end the VMG is better.

The same happens dead downwind and not only with this boat. With any modern performance boat is the same in what regards sailing downwind and regarding VMG and they are faster that way VMG than any older boat.

Regards

Paulo


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## souljour2000

There's alot of folks in here who are interested in planes also I have noticed so as a one time pilot in my late teens and albeit I had only three solos in small cessnas...this discussion of different boats make me think of different sorts of aircraft....seems that this is like comparing say a Cessna 172 vs. an aerobatic plane...The Cessna 172 is generally alot slower but stable over a wider envelope of conditions...big drag- producing but stable vertical stabilizer(tail) and again a thick drag-producing wing that inhibits speed but allows high lift and high stall speeds...and good stability before it loses that lift in only highly unstable (low-speed or due to high pitch,angle of attack with correlating loss of lift, type conditions. 
The aerobatic sport plane like a Pitts with thin short wings can go a hell lot faster..but the pilot has to be on top of things because of the built-in instability stemming from the thinner less-lift producing wings...greater speed of landings (stall speeds),etc...turbulence will also likeley affect the aerobatic plane more...as well as having smaller cargo capacity,fuel capacity,etc...Meanwhile the Cessna will carry four and alot of gear a fairly long way but at much slower speed..You pick...depending on what you want out of your (plane)boat...In this case obviously, the Cessna is the light cruiser and the Pitts is the "racer"...


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## souljour2000

PCP said:


> Have you keep up with the thread?
> 
> Regarding tracking ability Bob Perry said (in one of his books, particularly about boat design):
> 
> *"It's often argued that a full- or modified full-keel boat has better directional stability, which is often referred to as "tracking ability." My experience is just the opposite. I have found that the further I can separate the keel form the rudder, the better a boat tracks&#8230; I'm a believer in the 'feathers on the end of an arrow' theory. In other words, keep the rudder as far aft as possible."*
> 
> of course there are bad designed fin keelers and bad designed full keelers but implying a broad generalization assuming that full keelers track better than fin keelers just does not make sense. In fact Bob Perry says the opposite, not as a rule but as a tendency.
> 
> Regards
> 
> Paulo


 That's fine but I suspect most would agree that in medium and up to 20 mph or so winds..the full keeler tracks just as well and with a much lighter helm....higher winds than that generate enough speed in the fin keeler's airfoil to develop the kind of lift where it will go upwind better than the full-keeler(especially shoal draught full-keeler like mine) and yes..it then "tracks better" but it's likely a bumpier ride than the guy in the full-keeler is having...and he is often only a few points more off the wind...or closer with a ketch or yawl. I will grant naturally you this might possibly be the critical difference that keeps you off a lee shore sometime....someone else's turn now...


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## mitiempo

souljour2000 said:


> ..it then "tracks better" but it's likely a bumpier ride than the guy in the full-keeler is having...


I disagree. I think you are assuming that all fin keel boats have shallow flat bottom hulls. True some do but there are all degrees in between as well.

Do you think this boat would have a bumpy ride?


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## souljour2000

mitiempo said:


> I disagree. I think you are assuming that all fin keel boats have shallow flat bottom hulls. True some do but there are all degrees in between as well.
> 
> Do you think this boat would have a bumpy ride?


 True. There are many heavy-disp. fin-keelers like that ...In my mind I was thinking of newer race-inspired fin-keelers with the long extended bulb-type keels and flat wide bodies...That boat there in the pic is alright in my book...kinda tubby though...lol..


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## mitiempo

souljour2000 said:


> True. There are many heavy-disp. fin-keelers like that ...In my mind I was thinking of newer race-inspired fin-keelers with the long extended bulb-type keels and flat wide bodies...That boat there in the pic is alright in my book...kinda tubby though...lol..


It is not what is considered a heavy displacement boat. 
It has a D/L ratio 256 and is thought of as a performance cruiser.

Tubby? With a beam of 12'2" and almost 40' overall length it is narrower than a Pogo 10.50 which is 6' shorter overall.


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## Daily Alice

Could you mention the name of the boat/model, LOA? And approx. year, perhaps? Thanks. Interesting point.



mitiempo said:


> It is not what is considered a heavy displacement boat. It has a D/L ratio 256 and is thought of as a performance cruiser. Tubby? With a beam of 12'2" and almost 40' overall length it is narrower than a Pogo 10.50 which is 6' shorter overall.


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## mitiempo

I thought most would know the design.


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## Daily Alice

I thought you were just being coy, sweetheart 

Seriously, even if I was almost d*mn certain, it's nice to remove all doubt, for us youngsters. A link to the data wouldn't hurt? Valiant 40-1 .



mitiempo said:


> I thought most would know the design.


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## wolfenzee

mitiempo said:


> I disagree. I think you are assuming that all fin keel boats have shallow flat bottom hulls. True some do but there are all degrees in between as well.
> 
> Do you think this boat would have a bumpy ride?


Some of the high performance fins....you can barely look down long enough to pick up your coffee with out going off course. My full keel was outfitted with a self-steering vane which was removed because the boat will sail for days on end with a lashed tiller.

My boat is 30loa, 25lwl, 8'9"beam, 5' dafft about15,000lbs....deepest point is at the base of the rudder post (transom hung rudder with slight rake to transom).


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## souljour2000

Thought it looked very familiar of late...there's been alot of discussion of valiant 40's lately...They have alot going for them certainly. I think that photo may have even been posted on another thread recently...I guess it is not that tubby really...especially compared to catalina 400 or Morgan OI's...
My old Morgan Columbia 40 is 10' 6" on the beam...39' and change loa...She comes in a bit over 7 knots theoretical..The bow itself may not have wave-piercing slender-entry...but being narrow...the whole boat does have wave-piercing form...also gives back some maneuverabilty lost by the full keel too...She has lots of storage and tankage... some reserve bouyancy with her overhangs...etc Agreed, they all have their plus and minus...one just has to find the boat that's right for you.....
I have felt lucky to get every boat I have had...And often just as happy to see 'em go...I said goodbye to my S&S Columbia 29 with some regret..but I'm over it..same thing with the Seafarer24..a fine daysailer and capable of occasional and select coastal work...Some day I'll want one of those back perhaps...I get old boats on the cheap...as long as they got some sailing left in them...I sail 'em as much as I can and then sell them for more or less what I got 'em for when something better comes along...I don't think there's much new under the sun , newer sailboats are still slow. Just often less comfortably so... IMHO. Now I got a boat I'd like to keep for awhile I think...that the guy in the 40-foot trawler is going to have a harder time sloshing me about in on the weekends...and while not discussed often...that kind of "performance" counts for alot in busy SW Florida channels...


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## mitiempo

Yes beam has increased a lot in the last few decades. I think the Valiant is a great design, not super light but not massively heavy either, and a good performing boat in most if not all conditions. A Valiant 40 won its class in the Swiftsure race out of Victoria last year. 

Even though it would be fun to sail a Pogo or one similar they wouldn't be my choice for an offshore boat. 
If I could have my ideal boat built it would be moderate displacement, virtually no overhang, narrow with balanced waterlines, fin keel with spade rudder right aft, interior similar to a 35' boat - but about 45' long. A smaller Sundeer.


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## mitiempo

wolfenzee said:


> Some of the high performance fins....you can barely look down long enough to pick up your coffee with out going off course. My full keel was outfitted with a self-steering vane which was removed because the boat will sail for days on end with a lashed tiller.
> 
> My boat is 30loa, 25lwl, 8'9"beam, 5' dafft about15,000lbs....deepest point is at the base of the rudder post (transom hung rudder with slight rake to transom).


Agreed. But I think a lot of this thread is about the extremes - flat bottom and narrow deep fin vs heavy full keel. My point is that there are moderate fin keel boats that do not have many of the vices that plague the superlights. There are also a few full keel boats that are quite light.


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## Daily Alice

Would that be the good "Captain Cicero"?

With the high performance fins you mention, would this issue (poor tracking, rapidly "going off course") relate more to the rudder design/placement and overall weighted balance of the boat, than the fin keel itself? Going back to the "feathers on an arrow" design idea, I found this in Coles' "Heavy Weather Sailing (6th ed., 2008, rev., Peter Bruce, "Yacht Design and Construction for Heavy Weather," p. 8):

"Small wetted area carries with it advantages that have resulted in the almost universal adoption of the short keel and separate rudder. Comparatively [to various full keel designs, just discussed] it means equal performance with less sail area, especially in light weather, or to windward when speeds are low. Using a short keel the required position of the ballast dictates the location of the CLR [center of lateral resistance]. This disadvantage can be lessened by locating disposable weights as far forward as possible, permitting the ballast keel to come aft, but such gains are limited and the best available strategy to move the CLR aft seems to be to use a large skeg and rudder. These serve the function of feathers on an arrow. Most new boats follow this pattern and, if the ends are balanced, they can behave well, exhibiting no loss of steering control, ability to heave-to or other good seagoing characteristics."

What do you think? A "large skeg and rudder" hardly sounds like most newer production designs!?



wolfenzee said:


> Some of the high performance fins....you can barely look down long enough to pick up your coffee with out going off course. My full keel was outfitted with a self-steering vane which was removed because the boat will sail for days on end with a lashed tiller.
> 
> My boat is 30loa, 25lwl, 8'9"beam, 5' dafft about15,000lbs....deepest point is at the base of the rudder post (transom hung rudder with slight rake to transom).


----------



## wolfenzee

Some of the pro fin posts use the extremes of the full (and its related cons) to support the pros of their fins (with out mentioning its related cons).


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## PCP

wolfenzee said:


> Some of the high performance fins....you can barely look down long enough to pick up your coffee with out going off course. My full keel was outfitted with a self-steering vane which was removed because the boat will sail for days on end with a lashed tiller.
> 
> My boat is 30loa, 25lwl, 8'9"beam, 5' dafft about15,000lbs....deepest point is at the base of the rudder post (transom hung rudder with slight rake to transom).


This thread is not a about a particular kind of fin keel versus a heavy long keeler. Long keelers are only heavy because at the time they were designed there was not available technology to make them light. Today you can design and build a light full keeler. The reason they do not exist is because it does not make sense. You can design an overall better boat with a fin keel or midified fin keel for any kind of sailing.

Again, this is not about light boats versus heavy boats not about beamy flat bottom boats against more narrow boats with a lot of rocker. You seem to associate fin keelers with racers and performance boats and your comparisons are always between a boat like yours or an heavy full keeler and a light flat bottom race derived performance cruiser. That makes no sense.

As I have said I think that there is not a right boat fore offshore work but several seaworthy types adapted to different sailors and different types of personalities and sailing tastes. For the ones that favor the type of motion and the slower ride of a medium-heavy boat there are plenty offers on the market, narrow and beamy...all with a fin or modified fin keel, or at least all that have a modern designed hull and not a design based on some 40 year's old sail boat.

Even the guys that love so much classic boats that have modern boats designed according their lines (narrow and with a lot of rocker) and have the money to go to a good NA to make their dream true end up with a classic boat with a fin keel and a spade rudder just because it is a better technical solution and I don't mean for racing but for overall sailing.

I love traditional boats and old boats and it make all sense to preserve those boats and even in some cases to build replicas, but not because they sail better. Just because they represent the best it was made at that time. They all will certainly offer great sailing....but obviously not an overall better sailing than a modern designed boat, otherwise modern boats would only be improvements of those designs and not completely different boats.

Regards

Paulo


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## skygazer

As an ex archer, I have trouble with the feathers on the end of the arrow analogy. The feathers are surrounded fully by the medium they are passing through, it would be a great analogy for a submarine.

I do understand the gain in leverage by moving the rudder to the stern. But in this case the "arrow" is skimming the surface, with only one feather in the medium. And many times I have watched gusts cause boats with stern mounted rudders to lift the rudder out of the water as they ahem - politely - "round up" or what I would call broaching, something I hate. With the rudder lifting out of the water they have no helm control at all. The deep rudder on the end of a full keel does not lift so easily.

That is my personal observation. But what I wonder is, doesn't the turbulence from the fin disrupt the water enough to lessen the effectiveness of the rudder even when it is fully submerged? Isn't all design lift on high aspect foils based on an undisturbed fluid? Don't planes drop in turbulence? Or just the ones I'm on


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## Faster

As I understand it, the foil shape of the keel provides the actual lift when the boat is properly sailed at the correct angles and leeway (in relatively undisturbed water - but in reality all of this is working in very non linear 3D so 'undisturbed' is a probably a strong assumption)... the foil of the rudder is a low drag shape but the additional 'lift', if any, is more a function of the slight rudder angle with the optimum weather helm at play.

And I think most broaches happen because the rudder stalls, initiating the broach, after which the rudder may indeed be 'lifted' out of the water - but the damage was done before that. Some fin keelers, esp from certain eras, were indeed 'broach machines' but usually mostly when over-pressed. We've owned a few of these styles of boats and with careful sail selection and decisions, along with course selection, we had few incidents despite sailing over 20 years in a notoriously heavy wind area.

There's lots of room for both camps - I appreciate the saltiness of the full keelers of all sorts, but personally appreciate more the attributes of a lighter, more agile fin keel boat for our region and sailing habits. Quite likely in terms of overall sensibility the various compromises like the famous Brewer Bite, and the modified long chord fins from Bob Perry and the like make the most of both points of view.


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## wolfenzee

As this is in the "cruising @ liveaboard forum" rather than a performane and raceing forum....the tracking ability and smoother handling of a full would be preferred.


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## Rockter

*PCP*

_I love traditional boats and old boats and it make all sense to preserve those boats and even in some cases to build replicas, but not because they sail better. Just because they represent the best it was made at that time. They all will certainly offer great sailing....but obviously not an overall better sailing than a modern designed boat, otherwise modern boats would only be improvements of those designs and not completely different boats._

You are just being silly with comments like that. What on earth does "sail better" mean?

For me, its a long keeled boat every time. I have owned one for 20 years, a Union Polaris 36. If it sank (heaven forbid), I would buy another one.

I have sailed on deep fin boats. They are faster, they point higher, but they are not for me. They don't "sail better" for me. They never will. All that helm correction and tweaking? You can keep it.

Give me a 36 ft boat, 22,000 lb displacement, and a full keel cast into the fibreglass. You can have your deep fin keels, and bolt them on, and you can point higher and go faster. You can even have one of those lovely spade rudders too.

As for "Sail better"?... for you, yes, but not for me, no matter when it was built.
.


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## goboatingnow

> I have sailed on deep fin boats. They are faster, they point higher, but they are not for me. They don't "sail better" for me. They never will. All that helm correction and tweaking? You can keep it.


I owned a Beneteau 393, a very conventional fin and spade. with a bit of careful tweaking with the sail balance, she would sail upwind without a hand on the wheel.

Sea kindliness, etc etc has nothing to with long keels, its a function of the boat design , weight and the way they are driven. Long keels existed because that was the only way the vessel could be built. The technology did not exist to attach a heavy structure to a wooden frame.

Modern fin keels ( which itself is a broad family) are proven better hydro-dynamically and computer modeling has shown that decisively. Id argue that encapsulating a keel is irrelevant in whether its a fin or not.

Yes , I like old cars and old aircraft too. But I don't persist in arguing they are better then the modern computer designed versions.

If you like full keels ( i don't know where anyone is going to buy one new these days) that fine. No doubt you like old Jaguar cars too. But accept that modern naval architects with access to infinitely more knowledge and computation modeling do actually know what they are doing.

modern boats do "sail better", they are more efficient, faster in a given wind strength, more agile, more controllable ( try surfing) and significantly stronger per llb. Modern technology allows such vessels to maintain high speeds and punch through weather, that has older designs breaking up and so they heave to. Yes this is at the extreme end of the technology, but its shows where the trend is and what its capable of.

Upto the late 60s, the concept of taking a small boat across oceans, was generally regarded as madness, undertaken by a few lunatics, some actually knighted for it. This was because the basic craft, of the day ( and hence its design) simply wasn't up the job, and required enormous maintenance and some skill to achieve these tasks. Small boat design evolved from small coastal fishing technology of the day, such technology never envisaged crossing oceans.

Today anyone in a reasonable well fitted out "plastic fantastic" can cross oceans and circumnavigate. why, primarily because the basic technology in the boat is stronger, more resilient, and efficient. Arguably the sailing skill of the owner is less, but the boat makes up for it.

A boat is a machine, technology moves forward, something designed years ago , simply cannot be better or even as good, the knowledge simply wasn't there. Boats like anything else are a product of continuous evolving technology, there is no historical "sweet" spot.

Dave


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## PCP

Rockter said:


> *PCP*
> 
> ...
> You are just being silly with comments like that. What on earth does "sail better" mean?
> 
> ....
> .


This has been a civil discussion and calling me silly doesn't add any value to your point of view and I prefer not comment on about what it says about you.

Sailing better is sailing better, faster in all points of sail, better tracking ability better pointing ability, same sea motion (for the same type of hull and weight), more light on the helm, more responsive, turning better under engine on forward motion and incomparably better on backward motion, in one word, sailing better.

Regards

Paulo


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## Rockter

*PCP :*

_This has been a civil discussion and calling me silly doesn't add any value to your point of view and I prefer not comment on about what it says about you.

Sailing better is sailing better, faster in all points of sail, better tracking ability better pointing ability, same sea motion (for the same type of hull and weight), more light on the helm, more responsive, turning better under engine on forward motion and incomparably better on backward motion, in one word, sailing better._

Then that's fine for you. Maybe in your world, downwind in a big Atlantic swell, day-after-day of it, your boat design is better for you. And you like deep fin keels and you like the idea of them being held on by bolts, and you like the cantilever stresses imposed on a spade rudder. And you clearly like helm sensitivity.

I don't.

No, give me a long keel, give me a keel-hung rudder, and cast the keel into the GRP so I don't have to worry about those keel bolt things. And give me a ship that is slower to respond to sea and helm.

That's for me.

Yea, because it "sails better" for me.

If anyone tells me otherwise, then they are being silly.


----------



## PCP

Rockter said:


> *PCP :*
> 
> _This has been a civil discussion and calling me silly doesn't add any value to your point of view and I prefer not comment on about what it says about you.
> 
> Sailing better is sailing better, faster in all points of sail, better tracking ability better pointing ability, same sea motion (for the same type of hull and weight), more light on the helm, more responsive, turning better under engine on forward motion and incomparably better on backward motion, in one word, sailing better._
> 
> Then that's fine for you. Maybe in your world, downwind in a big Atlantic swell, day-after-day of it, your boat design is better for you. And you like deep fin keels and you like the idea of them being held on by bolts, and you like the cantilever stresses imposed on a spade rudder. And you clearly like helm sensitivity.
> 
> I don't.
> 
> No, give me a long keel, give me a keel-hung rudder, and cast the keel into the GRP so I don't have to worry about those keel bolt things. And give me a ship that is slower to respond to sea and helm.
> 
> That's for me.
> 
> Yea, because it "sails better" for me.
> 
> If anyone tells me otherwise, then they are being silly.


Responds to helm is the same as being sensitive or at least it was what I wanted to say.

Regarding preferring a full keel to a fin fin keel or modified fin keel bluewater boat based on the fear of losing the keel that makes no sense. There is not a single case of a bluewater designed fin keeler boat that has lost the keel, I mean boats like Halberg Rassy, Najad, Malo, Passport, Vailant and many others that are designed thinking in offshore extended sailing.

Regarding that thing of calling me silly for stating the obvious, as you can see by the post bellow I was not trying to say to anyone what kind of boat they prefer to sail. Some even prefer to sail XV century Caravela replicas:










and they would have more pleasure sailing then than sailing a modern boat. That's more than OK to me and I have already said that.

But I am pretty sure that they would not say that they prefer to sail a XV century old boat because it sails better than a modern sail boat. That would mot make sense as it does not make sense saying that one prefers a long keel 50 year's old design sailing boat because it sails better than a modern offshore medium height cruising boat and that is not going to change by the fact that you insist in call me silly.



Rockter said:


> *PCP*
> 
> _I love traditional boats and old boats and it make all sense to preserve those boats and even in some cases to build replicas, but not because they sail better. Just because they represent the best it was made at that time. They all will certainly offer great sailing....but obviously not an overall better sailing than a modern designed boat, otherwise modern boats would only be improvements of those designs and not completely different boats._
> 
> You are just being silly with comments like that. What on earth does "sail better" mean?...
> As for "Sail better"?... for you, yes, but not for me, no matter when it was built.


Sailing better is not a fantasy but an objective thing. As I have said sea motion and boat behavior depends mostly on hull shape and displacement. Has the designer and builders of the Gozzard had said after trying the boat on both configurations (Full keel and modified fin keel):

*"In 1999 we modified the keel again (along with a complete redress of the hull structure). This time we further decreased the wetted surface and used a real 64 Series NACA foil section. The new keel was a little shorter (fore and aft), taller and far more defined. Still too large to be called a fin keel but at the same time it could not really be called a modified full keel either. The results were very positive. The biggest improvement is in performance without any noticeable loss of sea keeping ability. In fact the new design is easier to control, lighter on the helm and obviously faster in all points of sail."*

I don't like particularly Ted Brewer as a NA (the designer of Gozzard) that seems quite conservative in its designs not exploring new materials and new technical possibilities nor design improvements. Bob Perry has reached the same conclusion not 15 years ago but 40 years ago when he designed the Vialant:










Regards

Paulo


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## Rockter

PCP :

Why on earth would "lighter on the helm" attract anyone on a long haul?

I remember 27 days with a long keel and heavy helm.

I would not trade it for anything.

But then again, maybe if I had a lighter helm my boat would have been more fun, or "sail better" or something?

Try a long haul sometime on that Benetau. Steer it manually too. Then try a long keeler with a heavy helm. It'll be educational. But don't compare the two ships around the marks on a day race, or you will find that you will like your Benetau so much that you will never touch a long keeler ever again.

Better still, take your Benetau out into a mid Atlantic gale, wait for the rollers to build, and run before them off the quarter. When you do, you may find helm sensitivity is not one of your priorities. Nor speed.

I have done a long haul with a long keeled ship. By contrast, a single afternoon with a deep fin convinced me it was not for me. It was fun, but I wouldn't want to own it. That decision was nothing to do with the age of the ships, or materials, or computers.

No. Deep fins are simply not for me.

I don't like them.

Give a ship like this a fair trial...

http://sailboatdata.com/viewrecord.asp?class_id=3306

.... in the rough stuff, running before a big sea.

You may get to like that keel more than you think.


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## PCP

Rockter said:


> PCP :
> 
> Why on earth would "lighter on the helm" attract anyone on a long haul?
> 
> I remember 27 days with a long keel and heavy helm.
> 
> ...


An heavy helm does only mean that the boat is not well balanced. Some full keel boats have an heavy helm even with a rightly balanced sails.

A boat with a light helm does not mean that it has an inferior tracking ability or that it stays less on its course, just that you need to make less force to maintain or alter course and therefore will require less energy from the autopilot.

If you have the sails balanced (as any good sailor would have) on a well designed boat, as most on these days, you can let go the wheel and the boat will continue happily its course.

Regards

Paulo


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## souljour2000

I want to do a yawl-conversion on my 18,200 lb Columbia 40 full-keeler...gonna be awhile though...need to address the steel skeleton though should just be preventative...like drenching it with rust-inhibitor...will eliminate it altogether down the road..and then the hydraulic-armed centerboard...same thing for now...rust-inhibitor...then I don't know until further examination of the components... but need to fix and re-enforce the foredeck first actually...got a sweet drop-forged 6"x6" base ss sampson post from old-school days I am gonna put there...yawl-conversion eventually as I said is a possibilty,,and might not be too much more costly than a self-steering system or a new but usually questionable autopilot...I know that being narrow at 10' 6" the boat will be a failry wet ride at hull speed(7.16 kts) but she should be fairly stable surfing and she can punch through oncoming chop I am sure...and the thing is like the rock of gibraltar at anchor in 20 mph winds...sippin rum...wish I was on her now...I love her...Yes..am still in honeymoon stage...don't ruin it...fin-keelers are fine...whatever.. Just happy with what I got...and that is.... a boat I feel can go alot of places...


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## Rockter

*PCP :*

By "lighter on the helm", they mean that it needs less input at the helm to change course. They are not talking about sail balance.

I would be very interested to see that Benetau of yours hold its course on a broad reach.

Hands off with no autopilot?

My long keeler won't.

That Benetau must be quite a ship to hold a broad reach hands-off.


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## Ferretchaser

Rockter said:


> *PCP*
> 
> _I love traditional boats and old boats and it make all sense to preserve those boats and even in some cases to build replicas, but not because they sail better. Just because they represent the best it was made at that time. They all will certainly offer great sailing....but obviously not an overall better sailing than a modern designed boat, otherwise modern boats would only be improvements of those designs and not completely different boats._
> 
> You are just being silly with comments like that. What on earth does "sail better" mean?
> 
> For me, its a long keeled boat every time. I have owned one for 20 years, a Union Polaris 36. If it sank (heaven forbid), I would buy another one.
> 
> I have sailed on deep fin boats. They are faster, they point higher, but they are not for me. They don't "sail better" for me. They never will. All that helm correction and tweaking? You can keep it.
> 
> Give me a 36 ft boat, 22,000 lb displacement, and a full keel cast into the fibreglass. You can have your deep fin keels, and bolt them on, and you can point higher and go faster. You can even have one of those lovely spade rudders too.
> 
> As for "Sail better"?... for you, yes, but not for me, no matter when it was built.
> .


I could not have put that better myself. As far as reversing in tight marinas goes, I have a bow thruster in mine that takes the guesswork out of that as well.










ATB

Michael


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## wolfenzee

As far as manuvering in tight spaces I find heavy displacement has it's advantages. Put it in reverse and throw the helm over one way and just as you are starting to move backwards, put it in forward and throw the helm over the other way, this allows you to turn the boat on it's own axis...I have even seen it done with a 100' schooner (and no bow thruster).


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## goboatingnow

> That Benetau must be quite a ship to hold a broad reach hands-off.


never mentioned a broad reach.

dave


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## Cruisingdad

If you are planning on SW Florida and key and Bahamas, you need a shallow draft boat. Period. DOn't listen to these guys with 7-9 foot drafts in the NE or PNW. I have about 5'10 (6 foot after all the pots and pans) and I run aground ALL THE TIME!! And I know the area very well.

You are starting in FMB. Unless you don't mind sitting a lot and waiting for a tide or running aground in the miserable mile, go shallow draft. Six foot max. THis is typically a wing keel. SOme modified fulls will work too.

As far as the the theoretical debate about which is better, for racing and deep water, I would always go fin. But for cruising anywhere that has shallow water, 6+ is tough, and anything at 7 for much of the area I have been is a waste of time. That has been my experience. I personally would never own a deep draft boat which rules out most fins for me. I don't like 6'!

I know the area you are in. Trust me. I have seen 3' draft motor boats run aground all the time. 

Brian


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## PCP

Hi! It seems that what really works there is a Pogo, a Malango an Opium or even a Southerly, boats that combines the advantages of a deep big draft fin keel with the advantages of a motorboat draft

Regards

Paulo


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## blt2ski

boy Brian, if you run aground a lot down there with NO tide change, I do nto want to know how you would do up here in the northern climes with 12-15+ foot tide changes. I see 7.x-22.x' at my slip on extreme tide change days on the depth guage!

at the end of the day, one needs a keel that works for them, hull shape that works for them, hull strength for conditions they will meet etc. Not sure a hershoff(sp) 12.5 will make a good ocean going rig in many conditions, even tho designed by a known great architect, full keel etc. that open cockpit will probably kill it! if the light scantlings do not in the mean time.

Marty


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## mitiempo

You can touch bottom with a 9' draft or a 2' draft - the trick is to avoid it with any boat.


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## sea_hunter

For those that state with utmost authority that one keel be better for the Florida shoals than the next; nonsense. If you continue to ground, please learn to check your charts and tide tables. If the ground is ever shifting why is it that we don't hear of freighters and other naval ships constantly aground in the southern states? Keel length is relative. A 6 foot draft on a 50 foot boat that IS a shallow draft design. My issue with fin keels is the inherent structural incongruities with an increased (and increasing) possibility of catastrophic failure. A cursory search on Google of "boat looses keel" is disturbing to say the least. Keel type is argumentativly as personal a preference as whether or not you have a ketch, sloop or power boat. If you still keep grounding, perhaps some training wheels might be in order.


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## PCP

sea_hunter said:


> For those that state with utmost authority that one keel be better for the Florida shoals than the next; nonsense. If you continue to ground, please learn to check your charts and tide tables. If the ground is ever shifting why is it that we don't hear of freighters and other naval ships constantly aground in the southern states? Keel length is relative. A 6 foot draft on a 50 foot boat that IS a shallow draft design. My issue with fin keels is the inherent structural incongruities with an increased (and increasing) possibility of catastrophic failure. A cursory search on Google of "boat looses keel" is disturbing to say the least. .....


Not to mention big sail yachts from whom a 3.00m draft is shoal draft. You a smaller boat or a boat that can raise the keel you can go to more places and be more nearer from the beach, or on the beach but that's all.

Regarding losing the keel if you pay attention those boats are very high profile racers that have been built to be as light as possible and that are to be used with regular inspection checks to all stressful parts of the hull. There are no cruisers losing keels, not even big mass production cruisers at least to in any meaningful number.

There are cases where boats are thrown to the coast by storms or bad navigation and even so the fin keels survived. You have the recent case of that Sydney another one with a Mini class racer that was put again in the water and sustained not only the efforts on the way to the beach but also the efforts when the boat was pulled again (by boats) to the sea again and you have for instance these cases:






Regards

Paulo


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## wolfenzee

I live in the Pacific North West with over 10ft tidal change, I draw 5' so theoretically anything that the chart lists being wet at mean low is navigable at high tide....theoretically. I grew up on the Chesapeake, 3' tidal change and if you ran aground it was sand or mud...up here it is rock so the idea of running aground is unnerving (ironically the only time I have run aground here was in the mouth of the Frazier river, sand) when I was in BC even though I knew the charts were in meters...I treated them as feet.
Joshua Slochum said "Anyone who says they have never run aground has never been anywhere (or is lieing)".


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## sea_hunter

Paulo, while I enjoyed your video posts, and there appears to be little or no damage to the keels or the hull keel joint, it requires a experience eye to determine how bad the damage. Just ask the crew of the Cynthia Woods.

Wolfenzee, having spent 35+ years boating the PNW, some of it commercial fishing, some of it cruising throughout many rivers and inlets of BC, Alaska and Washington including the Fraser, a river that moves 20 million tons of sediment every year. Keeping this in mind, if you're outside the channel markers on any arm of the Fraser River Delta you're on your own.
Your comment


> when I was in BC even though I knew the charts were in meters...I treated them as feet.


This should have actually been beneficial as 1 meter is about 3 feet. If your were siting in 5 meters of water, thinking it was 5 feet, it would be closer to 15 feet; so I really don't understand where you're going with this thread, other than sinking deeper into the sand.
By the by, the quote you attribute to Slocum wasn't actually by him and the fact that his circumnavigation took place in 1909, effectively removes him from the argument with today's availability of modern charts, GPS and the like. (I have to add that Slocum disappeared in November 1909 while aboard his boat, the Spray) While I applaud your attempt of rationalizing incompetence, it's a ludicrous idea that in these modern times with the availability of updated charts and depth sounders that "you're not a boater till you've grounded out". Perhaps this argument should be employed in the defense of the _Costa Concordia's_ captain.

At high tide, fish eat ants; at low tide, ants eat fish. ~ Thai saying.


----------



## PCP

sea_hunter said:


> Paulo, while I enjoyed your video posts, and there appears to be little or no damage to the keels or the hull keel joint, it requires a experience eye to determine how bad the damage. Just ask the crew of the Cynthia Woods.
> 
> ....


This one I saw by myself. This guy run on rocks doing over 6K. Brand new boat

The lead keel was bent but not the slightest damage on the outside joint or the interior frame work that distributes the loads or on the attachment points.



















Regards

Paulo


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## Rockter

PCP :
With a long-keeled ship, the keel will not bend like that.
And as for "not the slightest damage", well, for me, read "not the slightest visible damage".
I wonder how it would slam in a big forward sea?


----------



## PCP

Rockter said:


> PCP :
> With a long-keeled ship, the keel will not bend like that.
> And as for "not the slightest damage", well, for me, read "not the slightest visible damage".
> I wonder how it would slam in a big forward sea?


No, I had talked with the guys from the shipyard. No damage at all except a bent lead keel.

You have to decide what is being discussed T*he discussion was about keels falling off*. Regarding the bent keel this is an all lead keel on a fast cruiser-racer. Keels on medium weight cruisers like the ones on the movies are stronger.

Regarding what would have happen with a full keeler hitting at full speed rocks well I guess it would have depended on the boat. The keel would not bent but the damages sustained on the keel and hull could be far more expensive to repair than a piece of bent lead. Jeff has explained already that quite well on a post on this thread.

Regards

Paulo


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## puddinlegs

Sail the boat you like and fits your mission. This isn't a fact based argument thread, its opinion. As far as safety and efficiency, the argument about 'fin' vs. full was over and the door nailed shut with Mr. Perry's Valiant 40 and the Cal 40. Boats of BOTH types (full and fin keel) sail successfully pretty much anywhere people sail. Sail what you want and have fun doing it, but don't make an argument rationalizing what millions safe ocean miles has proven to work very very well. So much so that full keel boats are becoming rare.


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## Chadfunk48

sea_hunter said:


> For those that state with utmost authority that one keel be better for the Florida shoals than the next; nonsense. If you continue to ground, please learn to check your charts and tide tables. If the ground is ever shifting why is it that we don't hear of freighters and other naval ships constantly aground in the southern states? Keel length is relative. A 6 foot draft on a 50 foot boat that IS a shallow draft design. My issue with fin keels is the inherent structural incongruities with an increased (and increasing) possibility of catastrophic failure. A cursory search on Google of "boat looses keel" is disturbing to say the least. Keel type is argumentativly as personal a preference as whether or not you have a ketch, sloop or power boat. If you still keep grounding, perhaps some training wheels might be in order.


The seafloor is ever shifting... that's not an "if" it can be seen on anyones depthsounder from one year to the next. Because freighters and navel ships use channels that are regularly dredged and monitored for depth.


----------



## wolfenzee

sea_hunter said:


> Paulo, while I enjoyed your video posts, and there appears to be little or no damage to the keels or the hull keel joint, it requires a experience eye to determine how bad the damage. Just ask the crew of the Cynthia Woods.
> 
> Wolfenzee, having spent 35+ years boating the PNW, some of it commercial fishing, some of it cruising throughout many rivers and inlets of BC, Alaska and Washington including the Fraser, a river that moves 20 million tons of sediment every year. Keeping this in mind, if you're outside the channel markers on any arm of the Fraser River Delta you're on your own.
> Your comment
> This should have actually been beneficial as 1 meter is about 3 feet. If your were siting in 5 meters of water, thinking it was 5 feet, it would be closer to 15 feet; so I really don't understand where you're going with this thread, other than sinking deeper into the sand.
> By the by, the quote you attribute to Slocum wasn't actually by him and the fact that his circumnavigation took place in 1909, effectively removes him from the argument with today's availability of modern charts, GPS and the like. (I have to add that Slocum disappeared in November 1909 while aboard his boat, the Spray) While I applaud your attempt of rationalizing incompetence, it's a ludicrous idea that in these modern times with the availability of updated charts and depth sounders that "you're not a boater till you've grounded out". Perhaps this argument should be employed in the defense of the _Costa Concordia's_ captain.
> 
> At high tide, fish eat ants; at low tide, ants eat fish. ~ Thai saying.


The only times I ran aground on the Frazier was once when avoiding bine run over by a tug and the other when I was waaaaaay off shore during low tide in a year that was running way below mean (that delta extends really far out). Each time was a slight bump...the first I just reversed off of the other was simply an unerving bump followed by thropuwing the helm hard over.


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## Woodvet

Great advice in here. I have almost always had full keels but the drag and (as mentioned) the beer gut do assure me they are best design. Many older traditional boats have these monstrosities in draft and we have always been told in the wide open app the tracking was better. The fin Keel is by far the quicker but if any rule holds fast in an ocean vessel it is that there are always extenuating circumstances. Especially when it comes to a static design trying to cope with a dynamic environment. 
While down in the Caribbean where coral heads can surprise you and charts can't help you may just kedging off some coral reef. It happen's! A Brewer's bite or the full on protected rudder aft of the brick outhouse keel may be just the thing. There's also more questions and with sailing always another answer. The ability of a vessel to back or maneuver in close quarters. It's likely that such a question as asked at the beginning of this thread may need qualifying. "What is it that the owner intends with the boat."


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## arja

So, full keel with a retractable centerboard is an great option. I have had a 1967 Hinckley Bermuda 40 yawl since 1988 that needs 4'4" with the board up and 9'7" with the board fully down. Coordinates the need for a fin when needed with the security of a full keel and rudder/prop protection while handling a shallow body of water like the Bahamas or Great Salt Pond on Block or Narragansett Bay, where I keep her. She handles well when going to weather, beaming or running, and the centerboard makes a difference upwind. Will she ever be a race horse, no. But enjoying shallow water is a delight.


----------



## SkywalkerII

Arja

Good answer!

Tartan 27, keel centerboard. Draws 3' 2" board up, 6'4" board down.

Very happy with the compromise. Enough performance, nice motion, gets in the skinny water.

All boats are a list of compromises. Everyone has to find their own list.

Skywalker
T27 #249


----------



## wolfenzee

Fin keels (as a whole ) are quicker than full keels (as a whole ). It doesn't take much wind to get my full up to hull seed...and some fins really poke along. Compareing ALL fins to ALL fulls to prove your point is generlizing too much.


----------



## puddinlegs

If full keels were as a rule, faster, every race boat on the planet would sport them. They aren't, but that's not really germane to the argument... which was what?  

Personally, I'd have a B-40 because it sails well enough for my mission and has the prettiest shear spring ever put to paper. Wide side decks are also a huge plus for my preferences. And did I say it's just a beautiful boat with half the interior volume of anything made in the past 2-3 decades?


----------



## sww914

My full keeled cutter sails like a dream, especially on a beam reach, I don't need to touch the wheel for an hour or two at a time if the swell isn't too big. It has survived three hurricanes. It powers through waves that would stop a lighter boat. It is extremely comfortable at anchor. It feels like a tank.
It turns slowly. It bangs on the dock all night if we're in a marina with a cross current. In reverse, I don't usually know what will happen until I'm backing at 3 knots or better. Usually the wrong thing happens.
I don't worry about bumping the keel on something, ever. I might worry about the getting stuck part, but the bump damaging my boat? No.


----------



## Cruisingdad

blt2ski said:


> boy Brian, if you run aground a lot down there with NO tide change, I do nto want to know how you would do up here in the northern climes with 12-15+ foot tide changes. I see 7.x-22.x' at my slip on extreme tide change days on the depth guage!
> 
> at the end of the day, one needs a keel that works for them, hull shape that works for them, hull strength for conditions they will meet etc. Not sure a hershoff(sp) 12.5 will make a good ocean going rig in many conditions, even tho designed by a known great architect, full keel etc. that open cockpit will probably kill it! if the light scantlings do not in the mean time.
> 
> Marty


Hey Marty,

The difference is that (for example) Dad has 22 feet under his keel at low tide. I generally have about six inches. We measure our water depth in inches under the keel down here! I generally anchor in about 7-10 feet of water. You have to get many miles offshore to even hit 20 feet of water! Anything over 6 and you simply will be very restricted on where you can go down here. I say, pick the keel for where you plan to cruise or how you intend to use the boat. In some areas, draft makes no difference. In some areas, it does.

BTW, hopefully we can meet up one of these days. Beautiful area.

Brian


----------



## Cruisingdad

sea_hunter said:


> For those that state with utmost authority that one keel be better for the Florida shoals than the next; nonsense. If you continue to ground, please learn to check your charts and tide tables. If the ground is ever shifting why is it that we don't hear of freighters and other naval ships constantly aground in the southern states? Keel length is relative. A 6 foot draft on a 50 foot boat that IS a shallow draft design. My issue with fin keels is the inherent structural incongruities with an increased (and increasing) possibility of catastrophic failure. A cursory search on Google of "boat looses keel" is disturbing to say the least. Keel type is argumentativly as personal a preference as whether or not you have a ketch, sloop or power boat. If you still keep grounding, perhaps some training wheels might be in order.


It's not the keel for me, its the draft.

The difference you need to understand is that in the PNW, when the tide comes in you have many feet under your keel assuming you stay in the channel. In Florida, the approach to my marina is about 6 - 7 at high. The middle of the channels is often 6. The ICW is supposed to be kept at 7+, but often is not. Many of the islands and approaches are simply not approachable with boats that have a deep draft.

I don't care what the tides are if you cannot get in at high because you have a deep draft boat, you cannot get in. That excludes a whole lot of beautiful areas down here that you can explore. Buy the draft for where you plan to cruise.

Brian


----------



## wolfenzee

I grew up on the Chesepeake with lots of sand and shifting shoals so if the draft of your boat allowed you to jump over board and push the boat off a sand bar (with your head above water) it was a convienient draft. I grew up sailing Person Tritons (draft 4') and my present boat has a draft of 5'..... more than I am used to but when I look around it doen't seem that bad.
I was in the ICW in a Triton, there was a boat not much bigger than ours aground, as we made our way over to it catiously (and were starting to run out of water) we asked how much they drew..."8'".....it was a fancy racing boat with a deep fin kee
l


----------



## blt2ski

Brian,
Your dad is in a DEEP marina. I'm literally in 7.x' with a -4 tide. I draw about 5.5'. A lot around here will be in the 8-10' with some of the lowest lows. I see 22 when it is at the highest of +12' that is right, 16' on the BIGGEST swings of the year. usually about 8-10' tween highest high, an lowest low. 

If your Dad makes it to fishermans bay on lopez, the channel is 5' at 0 tide. So if you try to go in at -2.5 which is a low low up there, we is screwed! I need to personally be at min +1' to get in, tried at .5 lst summer, bumped a few times. 

marty


----------



## PCP

Cruisingdad said:


> Hey Marty,
> 
> The difference is that (for example) Dad has 22 feet under his keel at low tide. I generally have about six inches. We measure our water depth in inches under the keel down here! I generally anchor in about 7-10 feet of water. You have to get many miles offshore to even hit 20 feet of water! Anything over 6 and you simply will be very restricted on where you can go down here. I say, pick the keel for where you plan to cruise or how you intend to use the boat. In some areas, draft makes no difference. In some areas, it does.
> 
> BTW, hopefully we can meet up one of these days. Beautiful area.
> 
> Brian


Hi Brian!, I agree with what you say except that thing about measure in inches the distance behind your keel. For being anchored you have always to count with the possibility of waves and at least one meter in flat water is the standard precaution even if you can get away with less. On very sheltered places with almost no tides, with sand or mud bottom sometimes I go to 30 cm of water behind the kell but I risk some hard bumbs if some cargo passes far away at speed and the wash comes there.

If you take, for safety measure, inches behind your keel instead of about a m while sailing or going under way it is more than natural that you will be plenty aground. As someone has said the bottom, except when it is rock changes, not that much, but really some inches is nothing regarding that.

On the conditions you describe a boat with even less draft seems more appropriated, a center-boarder or one of the modern swing keelers that were developed exactly for a situation like that aggravated by tides with more than 6 or 7m difference.

Of course all boats are a compromise and we get the one that fits us better. Solutions for a small draft, with exception of those modern boats with swing ballasted keels and some with keels that can go vertically up with a lead torpedo on the bottom, are always paid with a considerably worst sailing performance, but those boats that I am talking about are more rare and considerably more expensive not to mention that they give more maintenance than fixed keelers and the market offer is smaller...so, compromises again

Regards

Paulo


----------



## sea_hunter

Chadfunk48 said:


> The seafloor is ever shifting... that's not an "if" it can be seen on anyones depthsounder from one year to the next. Because freighters and navel ships use channels that are regularly dredged and monitored for depth.


That might have been true 50 or even 25 years ago, today ocean depths are continuously monitored by NOAA. Safe boating information can be found everywhere today; it's your choice how to employ and enjoy.
Integrated Models of Coastal Relief | ngdc.noaa.gov


----------



## PCP

sea_hunter said:


> That might have been true 50 or even 25 years ago, today ocean depths are continuously monitored by NOAA. Safe boating information can be found everywhere today; it's your choice how to employ and enjoy.
> Integrated Models of Coastal Relief | ngdc.noaa.gov


Better not believe that. In some places a single big storm can pill up up to 1m of sand in some places and even close a bar.

Even if it is monitored it will take several months to be included on the chart.

Regards

Paulo


----------



## sea_hunter

Aye, (agree to disagree) but that's where eyes, common sense, experience, local knowledge and a calibrated depth sounder come in dandy handy. If in doubt, rethink where you're going, and reread your chart as caution wins the day. That's why it's called sailing, not bumper boats.


----------



## Cruisingdad

PCP said:


> Hi Brian!, I agree with what you say except that thing about measure in inches the distance behind your keel. For being anchored you have always to count with the possibility of waves and at least one meter in flat water is the standard precaution even if you can get away with less. On very sheltered places with almost no tides, with sand or mud bottom sometimes I go to 30 cm of water behind the kell but I risk some hard bumbs if some cargo passes far away at speed and the wash comes there.
> 
> If you take, for safety measure, inches behind your keel instead of about a m while sailing or going under way it is more than natural that you will be plenty aground. As someone has said the bottom, except when it is rock changes, not that much, but really some inches is nothing regarding that.
> 
> On the conditions you describe a boat with even less draft seems more appropriated, a center-boarder or one of the modern swing keelers that were developed exactly for a situation like that aggravated by tides with more than 6 or 7m difference.
> 
> Of course all boats are a compromise and we get the one that fits us better. Solutions for a small draft, with exception of those modern boats with swing ballasted keels and some with keels that can go vertically up with a lead torpedo on the bottom, are always paid with a considerably worst sailing performance, but those boats that I am talking about are more rare and considerably more expensive not to mention that they give more maintenance than fixed keelers and the market offer is smaller...so, compromises again
> 
> Regards
> 
> Paulo


Hey Paulo,

Good to see you around!

I think you misunderstood what I was writing. My point was that I often have only inches of water under my keel. The bars change here with the storms, but it isn't really that. THe problem is that it is simply skinny water. For example, the Back Bay is about 5 feet, maybe 5.5 at high. The entrance behind Cay Costa resticts you to about 5-5.5 feet at high. The approach to my marina is maybe 6-7 at high. These are beautiful sailing grounds, but a deep draft boat (anything over 6) will prevent you from seeing much of it.

The Original Poster is based in the Fort Myers Beach area. I know that area extremely well. He would not be happy with a deep draft boat here. He could manage it in the keys, but even some of the approaches would be touch and go. Outside of these areas, like Tampa, Pensacola, or on around the east side, he would be fine. In the PNW he would be fine. But down here, it is miles wide and inches thin.

Take care my friend.

Brian


----------



## Cruisingdad

PCP said:


> Better not believe that. In some places a single big storm can pill up up to 1m of sand in some places and even close a bar.
> 
> Even if it is monitored it will take several months to be included on the chart.
> 
> Regards
> 
> Paulo


Absolutely agree. And many of the soundings on charts are very old. I use them as a guideline. For example, Chralie created a whole new cut through the barrier islands nort of Captiva. It is not on the maps. The tides and currents often shoal up the ICW which is "supposed" to be at 7-8 feet minimum. I have bumped at 6. But hey - it's what makes boating exciting!!

Brian


----------



## Cruisingdad

blt2ski said:


> Brian,
> Your dad is in a DEEP marina. I'm literally in 7.x' with a -4 tide. I draw about 5.5'. A lot around here will be in the 8-10' with some of the lowest lows. I see 22 when it is at the highest of +12' that is right, 16' on the BIGGEST swings of the year. usually about 8-10' tween highest high, an lowest low.
> 
> If your Dad makes it to fishermans bay on lopez, the channel is 5' at 0 tide. So if you try to go in at -2.5 which is a low low up there, we is screwed! I need to personally be at min +1' to get in, tried at .5 lst summer, bumped a few times.
> 
> marty


Hey Marty,

Ii think he is going to stay in Olympia some months and then start pushing north to Tacoma and then further from that. Not sure if he is agoing to keep him slip in Olympia very long.

He draws a solid 6, more like 6'2. Nice thing is his Mod Full Keel is easy to get off. I do like that over wings - being easier to get off if you do run aground.

Hope to see you out there. If you come, bring your dog. I will introduce her to Fatty!

Brian


----------



## sea_hunter

Me thinks if your measuring your anchorages in inches barely even feet ; where's your scope? Bizarre to say the least.


----------



## Cruisingdad

sea_hunter said:


> Me thinks if your measuring your anchorages in inches barely even feet ; where's your scope? Bizarre to say the least.


Inches under the keel.

I do not understand what is bizarre about that nor do I understand the relavence of scope on the discussion?

How many years have you cruised south florida and the keys again? Where do you sail?

Brian


----------



## wolfenzee

PCP said:


> Better not believe that. In some places a single big storm can pill up up to 1m of sand in some places and even close a bar.
> 
> Even if it is monitored it will take several months to be included on the chart.
> 
> Regards
> 
> Paulo


In the Cheasapeake sand bars shift faster than they can be monitored by NOAA....I remeber one little creek where there was a sand bar that went almost allthe way across the mouth....sometimes from one side, sometimes from the other, the locals would stick a marker out to let you know where the bar was at the moment (I remember one that had a sign on it that read "If you can read this you are probably aground").

That is one nice thing about the PNW the rocks don't move, with a 10'+ tidal change, what is possible at high tide compared to what the chart says can be very interesting, I remeber leaving Silva Bay up in BC by a route suggested to me by a "local" (when I asked my crew what the depth sounder said, he said "you don't want to know"). I got out with no problem.


----------



## GBurton

goboatingnow said:


> I owned a Beneteau 393, a very conventional fin and spade. with a bit of careful tweaking with the sail balance, she would sail upwind without a hand on the wheel.
> 
> Sea kindliness, etc etc has nothing to with long keels, its a function of the boat design , weight and the way they are driven. Long keels existed because that was the only way the vessel could be built. The technology did not exist to attach a heavy structure to a wooden frame.
> 
> Modern fin keels ( which itself is a broad family) are proven better hydro-dynamically and computer modeling has shown that decisively. Id argue that encapsulating a keel is irrelevant in whether its a fin or not.
> 
> Yes , I like old cars and old aircraft too. But I don't persist in arguing they are better then the modern computer designed versions.
> 
> If you like full keels ( i don't know where anyone is going to buy one new these days) that fine. No doubt you like old Jaguar cars too. But accept that modern naval architects with access to infinitely more knowledge and computation modeling do actually know what they are doing.
> 
> modern boats do "sail better", they are more efficient, faster in a given wind strength, more agile, more controllable ( try surfing) and significantly stronger per llb. Modern technology allows such vessels to maintain high speeds and punch through weather, that has older designs breaking up and so they heave to. Yes this is at the extreme end of the technology, but its shows where the trend is and what its capable of.
> 
> Upto the late 60s, the concept of taking a small boat across oceans, was generally regarded as madness, undertaken by a few lunatics, some actually knighted for it. This was because the basic craft, of the day ( and hence its design) simply wasn't up the job, and required enormous maintenance and some skill to achieve these tasks. Small boat design evolved from small coastal fishing technology of the day, such technology never envisaged crossing oceans.
> 
> Today anyone in a reasonable well fitted out "plastic fantastic" can cross oceans and circumnavigate. why, primarily because the basic technology in the boat is stronger, more resilient, and efficient. Arguably the sailing skill of the owner is less, but the boat makes up for it.
> 
> A boat is a machine, technology moves forward, something designed years ago , simply cannot be better or even as good, the knowledge simply wasn't there. Boats like anything else are a product of continuous evolving technology, there is no historical "sweet" spot.
> 
> Dave


Dave, evolution does not always mean "better". Things "evolve" for different reasons...in the case of a sailboat, evolution might mean that boats become cheaper, appear flashier, have a shinier finish and require a blazer to sail.(sorry but cant help but put in the picture of the beneteau the arch in here)










Also as others have pointed out, there were fin keeled boats 100 years ago, it has nothing to do with the technology not being available.

As far as your paragraph



> Today anyone in a reasonable well fitted out "plastic fantastic" can cross oceans and circumnavigate. why, primarily because the basic technology in the boat is stronger, more resilient, and efficient. Arguably the sailing skill of the owner is less, but the boat makes up for it.


I'm trying to imagine a catalina 30 out here off the Oregon coast compared to my Westsail 32 and coming to the conclusion that what you say is completely wrong. The person in the Catalina 30 is going to have to have far better sailing skills than the person in the heavier older design. That light fin keel boat will require much more attention to keep out of trouble.


----------



## CapnBilll

I like the new is better theory, except that like cars there has been a divergence in performance, and affordability. 

Take the mustang for example. The 60's era cars have undeniably more HP and quicker acceleration and top speed than the same model built in the 80's,...why? The 80's car weighs much less and is built with a much more advanced engine with computer controlled fuel injection, it should blow the doors off of it's older counterpart, except is doesn't,...why???

It was designed and built, not to go faster, but to comply with the new regs that forced it to pollute less, and more safety equipment, and be cheaper, and easier to build than it's legacy counterpart.

So are the new cars better? Well for what? Is my new Honda better than my old Mustang? well it get's better gas milage, it is quieter, and easier to drive, it has antilock brakes, and air bags, and a much better sound system than the old AM radio. The bumper is a styrofoam block incased in fiberglass, instead of chrome and steel. If I clip my mailbox it no longer damages the mailbox, but instead disintegrates into a cloud of white dust. But weighs way less than the steel bumper, and protects me better in a collision. 

I can cheaply drive coast to coast with no tuneup, no new spark plugs, and carb adjustments. I no longer keep a full tool kit in the trunk, with spare plugs, jets, carb floats, etc... Is it better??? I wouldn't want to race my old Mustang in it.


----------



## souljour2000

CapnBilll said:


> I like the new is better theory, except that like cars there has been a divergence in performance, and affordability.
> 
> Take the mustang for example. The 60's era cars have undeniably more HP and quicker acceleration and top speed than the same model built in the 80's,...why? The 80's car weighs much less and is built with a much more advanced engine with computer controlled fuel injection, it should blow the doors off of it's older counterpart, except is doesn't,...why???
> 
> It was designed and built, not to go faster, but to comply with the new regs that forced it to pollute less, and more safety equipment, and be cheaper, and easier to build than it's legacy counterpart.
> 
> So are the new cars better? Well for what? Is my new Honda better than my old Mustang? well it get's better gas milage, it is quieter, and easier to drive, it has antilock brakes, and air bags, and a much better sound system than the old AM radio. The bumper is a styrofoam block incased in fiberglass, instead of chrome and steel. If I clip my mailbox it no longer damages the mailbox, but instead disintegrates into a cloud of white dust. But weighs way less than the steel bumper, and protects me better in a collision.
> 
> I can cheaply drive coast to coast with no tuneup, no new spark plugs, and carb adjustments. I no longer keep a full tool kit in the trunk, with spare plugs, jets, carb floats, etc... Is it better??? I wouldn't want to race my old Mustang in it.


+1 Capt Bill...good post...


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## puddinlegs

...


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## Lou452

I have been looking at this thread from the start. It is long and has opinoins on both sides. Thats what makes it a good thread! I am glad I am not ready to buy yet. I think the right boat will find me. Having a great summer water temps are in the high 70s F nice and warm. Have Fun ... LOU


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## bvander66

Seakindness and stability, which has been hinted at in this thread, is affected my more than the keel shape. We have a full keel and while we love it, many times we wish we had a modified 3/4 keel to reduce wetted area and make us a bit more maneuverable. For cruising you should try and get an underbody with a solid skedge and firmly attached and protected rudder. One advantage of a full keel is the rudder is enclosed in an appeture which means we have much less worry about ref lobster/crab pot entanglements.
Stability is driven by underbody shape, wieght, CoB and length/beam ratio. Unfortunately a lot of modern hulls based on the charter market dont look like that. They tend to have a narrow fin keel, unprotected prop and rudder, and wide beam that stretches all the way to the stern, all things which dont contribute to stability or seakindness....and yet cruise the Bahamas/Caribean and you see lots of these boats out there because they tend to be readily available and usually affordable compared to a long range bluewater boat. The skippers either accept the rough ride in a seaway or sail in conditions which its tolerable.
Boats are a huge trade off, increased room below can detract from stability/seakindness. Strong numbers in stab and seakindness can result in poor performance (acceleration/maneuverability). Big thing for a buyer is to assess whats important to you and adjust accordingly.


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## Navstarr

LOL!

I am somewhat flabbergasted.....have any of you ever heard of Doug Peterson?


----------



## Navstarr

Also,

Wide sections, either fore,or aft, preferably both...make for reserve bouyancy. This is a good thing...the compromise being wetted surface and thus speed.


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## Jeff_H

Wide sections either end of the boat do not necessarily mean reserve bouyancy. That depends on how they are shaped. 

But wide bow sections mean a harder collision with waves and less moderated impact, so more pitching, and more rapid deaccelleration in each wave collision, and therefore a much less comfortable motion combined with less speed upwind in a chop. 

Wide stern sections generally mean better dampening so a little less pitching at a slower speed up wind.


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## Navstarr

Reserve buoyancy is a function of displacement...not shape.

It manifests itself...not only fore and aft, but athwart-ships as well. It makes a sailing ship "stiffer"...able to carry more sail.....it makes her ride up and over the sea-state...not plow into it! Furthermore, when a marine architect purposely adds reserve buoyancy to his loftings, he is compromising his choice of "shapes". And they will pretty much dictate the chine and tumblehome of the final drawings.

This thread is about full vs fin keel.
Given that modern (Non -Brit) designers tend to favor the beamier, plans....afterall, they can carry sail....are very roomy below...and they don't require keels that would plow up the Grand Banks! These more modern designs 
do have more wetted surface....so the choice of underbody is obviousy fin and spade!




That's why we shot you out of the water in 1812....we took "America's Cup a couple of decades later....and thwarted all your efforts to win it back. Should I go on?


----------



## wolfenzee

Jeff_H said:


> Wide sections either end of the boat do not necessarily mean reserve bouyancy. That depends on how they are shaped.
> 
> But wide bow sections mean a harder collision with waves and less moderated impact, so more pitching, and more rapid deaccelleration in each wave collision, and therefore a much less comfortable motion combined with less speed upwind in a chop.
> 
> Wide stern sections generally mean better dampening so a little less pitching at a slower speed up wind.


My boat is really wide on the foredeck (but not at the waterline) to keep the cockpit dry (an Atkin trait), this would make the boat a bit saucy unless you carried the amount of chain and anchor it was designed to, balanced out by the engine. Being a heavy displacement boat (15,000lbs) it does not decelerate when going through a wave. The big wineglass transom also provides a lot of reserve buoyancy and keeps the cockpit dry from that end.I guess that is just one of the advantages of a full keel over a fin.


----------



## Jeff_H

Navstarr said:


> Reserve buoyancy is a function of displacement...not shape.


Reserve Buoyancy is not really about displacement in the usual sense of the term. Reserve Buoyancy is about the change in volume as vessel places portions of the boat normally above the static waterline below the surface of the water. This occurs as trim changes or dynamics forces cause the boat to temporarily displace more or less than its actual weight or static displacement. Because of that, shape becomes important, especially if the discussion is considering the behavior of the boat in a seaway, which was my point above.

In and of itself, simply adding reserve buoyancy does nothing good for the boat, and improperly shaped or excessive reserve buoyancy can be detrimental to motion comfort and seaworthiness. But if the change of shape and increase of buoyancy occurs progressively as the boat changes trim, that increasing buoyancy can dampen rotation and slow the rate of change of motion.



wolfenzee said:


> My boat is really wide on the foredeck (but not at the waterline) to keep the cockpit dry (an Atkin trait), this would make the boat a bit saucy unless you carried the amount of chain and anchor it was designed to, balanced out by the engine. Being a heavy displacement boat (15,000lbs) it does not decelerate when going through a wave. The big wineglass transom also provides a lot of reserve buoyancy and keeps the cockpit dry from that end.I guess that is just one of the advantages of a full keel over a fin.


This is full of less than perfectly accurate statements but I'll see whether I can straighten them out for the record. 



wolfenzee said:


> My boat is really wide on the foredeck (but not at the waterline) to keep the cockpit dry (an Atkin trait), this would make the boat a bit saucy unless you carried the amount of chain and anchor it was designed to, balanced out by the engine.


This begins to address my point about shape, which is that Atkins was a master of modeling hulls and many of his designs are shaped so that progressively increase displacement above the waterline dampening the dynamic tendencies and minimizing accelleration and deaccelleration. Both the nicely flared bow and wine glass stern on your boat are perfect examples of that. Adding an anchor and chain in the bow and an engine in the stern, would also slow the accelleration and deaccelleration rates, but would increase the pitch angles which is why people think of boats of this era as having excessive pitch angles. (hobbyhorsing)



wolfenzee said:


> Being a heavy displacement boat (15,000lbs) it does not decelerate when going through a wave.


All boats, regardless of their weight decelerate when going through a wave. Its basic physics, but the rate of deacelleration is proportionate to the inertia of the boat, and the force it encounters. At this point, how much your boat 'feels' deacceleration relative to a lighter boat is only true relative to wave size.

To explain, being a heavier displacement boat, your boat tends to be slower changing direction for a given wave impact and so would tend to have less deaccelleration than a lighter boat. But mitigating against that is that because it does not change direction as easily, it also buries itself further into the wave, experiencing a greater impact force. In practice this means that in small waves, you would feel the impact less than a lighter boat, but as waves become larger and steeper you would feel each collision more than a lighter weight boat. At some point as the waves start to get large enough, neither a light or heavy weight boat will inherently feel the waves any more or less than the other due to their weight, with shape being a more significant determinant of how boat behaves due to the impact with the wave.

Now then in really big waves, a light boat will heave at a similar rate to the rise and fall of the surface of the wave. A heavier boat is more likely to get out of phase with the wave and feel a greater impact in the trough and negative gravity at the crest than the lighter boat.



wolfenzee said:


> I guess that is just one of the advantages of a full keel over a fin.


Actually it has nothing to do with whether you have a fin or full keel and not much to do with overall weight, and mostly to do with buoyancy and displacement distribution.

Jeff


----------



## Familycruisers

Everyone knows the best keel is a bilge keel, nuff said.


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## blt2ski

Doug Peterson?!?!?!?!?!

oh yeah, the guy the designed the peterson trapezoidal keels on many boats from the late 80s into the 90's. This included my mid 80s Jeanneau........

I would still take a current day fin/bulb over my current keel if I had a choice. Not sure if the boat I have would like the keel or not, ie do better per say. I would like a bit more ASSet if you would, for a bit more room in the cockpit. 

At the end of the day, ALL boats are compromises! as to how the end user wants to fill certain uses etc of the boat.

marty


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## wolfenzee

Some of these light weight fin keels almost come to a full stop when confronted with a large wave, yes mine does decelerate some, but not considerably.


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## Jeff_H

wolfenzee said:


> Some of these light weight fin keels almost come to a full stop when confronted with a large wave, yes mine does decelerate some, but not considerably.


And some do not, its not about the keel or the weight of the boat, but the shape of the hull and the distribution of the buoyancy and weight. But more significantly, a properly designed, longer boat with the same displacement as yours would feel the waves even less than you do since the impact would be less, but the momentum the same.


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## Stumble

Wolf,

I don't know what modern light weight fin keel boats you have sailed, but the ones I have been one do just fine in waves. There may be a lot of reasons to prefer a full keel over a fin, but performance is not one of them.


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## sea_hunter

Certainly while loading has all to do with reserve buoyancy, I believe that the CG has more to do with keel design. A long broad keel offers a more forgiving ride yet becomes more stiff on the reach, regardless of reserve buoyancy. Designers alleviate this by cutting back the keel. Reserve buoyancy may have more significance in boats with finely shaped fin keeps where the shape of the hull changes the shape of their hulls at speed, but displacement is displacement.


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## WDS123

Some boats are just well designed and well balanced -

It is a careful balancing act between wetted surface area vs. trim vs. center of effort vs. center of lateral resistance. There is quite of bit of art in balancing the oft conflicting parameters.

For example Steve Schock designed the Harbor 14,20,25, and 30 to have low wetted surface and balanced helm. He spent a lot of time adjusting the keel shapes and location to achieve the neutral helm these boats are known for.

A Harbor 25 sailor on SF Bay single hands most of the 100 days a year he sails. He sails out of Sausilito so he spends a lot of time in and around the slot. No autopilot. He says the boat is so nicely tuned, that he can leave tiller unattended for minutes at a time.

The longest he left the tiller unattended was 20 minutes ! He says the boat just tracks along.


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## Jeff_H

Sea Hunter- Could you please explain what you are talking about? It may be a linguistic issue but much of what you have written has little, if anything, to do with the way that these terms are normally used in yacht design or design theory, or with the behavior of a vessel.

For example: _"Certainly while loading has all to do with reserve buoyancy" _ The way that the term "reserve buoyancy" is classicly used, loading has little, if anything t0 do with reserve buoyancy. As I read your sentence, I would suggest that you are mistaking (reserve) "carrying capacity" for "reserve buoyancy". These are two very different and not necesarily related concepts.

Or, "I believe that the CG has more to do with keel design." CG is only affected by weight distribution. While the type of keel and the profile and section of the keel affords the designer more or less ability to move the CG around, the type of keel and the profile and section of the keel does not in and of itself impact the CG of the boat. To provide an example to explain this, you could have an three boats the identical type of keel and with the same profile and section of the keel, but one uses cast lead, the second cast iron, and the third has a timber keel. Obviously each of these materials would move the CG around vertically, and in most cases, longitudinally as well.

Similarly, _"A long broad keel offers a more forgiving ride yet becomes more stiff on the reach, regardless of reserve buoyancy."_ A broad, meaning a transversely wide keel in conventional yacht design useage, while more forgiving in terms of stalling has litte or nothing to do with stiffness (form stability), reaching ability or reserve buoyancy.

None of the rest of_ "Designers alleviate this by cutting back the keel. Reserve buoyancy may have more significance in boats with finely shaped fin keeps where the shape of the hull changes the shape of their hulls at speed, but displacement is displacement." _ makes any sense or has any accuracy, except that "displacement is displacement."

Respectfully,
Jeff


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## skygazer

Jeff_H said:


> Sea Hunter- Could you please explain what you are talking about? It may be a linguistic issue...
> 
> Respectfully,
> Jeff


Thank you Jeff, I read and reread that post several times, and could not understand any of it. Glad it is not just me!


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## sea_hunter

Reserve buoyancy is a hulls ability to carry a load over and above displacement. Anything above the waterline, (with exception to a non watertight structure ie wheelhouse is not included) is reserve buoyancy.


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## Jeff_H

Sea Hunter, 

I am glad that you clarified what you are thinking. At least as you are describing it, (i.e. "Reserve buoyancy is a hulls ability to carry a load over and above displacement".) that is not in keeping with the way yacht and ship designers use the term, "Reserve buoyancy". What you are describing rarely if ever is considered as a part of yacht design. To some extent you are describing something like the total displacement of the submerged vessel less its normal buoyancy, which is not terribly relevant even in an extreme seaway. 

More relevant in understanding the behavior and characteristics of the vessel is carrying capacity which is the amout of weight that a vessel can carry before the load has a significant impact on performance and safety. Also more relevant is the impact of hull shape on reserve stability, the angle of vanishing stability and area under the stability curve. 

But none of these are inherently associated with whether the boat has a full or fin keel. 

Jeff


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## sea_hunter

That's my point, reserve buoyancy has nothing to do with keel type. Displacement and CG are more important.


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## Jeff_H

And just to be clear for someone trying to follow this, as the terms are normally used, displacement and Center of Gravity have little to nothing to do with 'reserve buoyancy' either. But when evaluating motion, carrying capacity and stability of a vessel, weight distribution and buoyancy distribution are far more critical than the overall displacement of the vessel, or its keel type.


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## sea_hunter

jeff_h:905984 said:


> and just to be clear for someone trying to follow this, as the terms are normally used, displacement and center of gravity have little to nothing to do with 'reserve buoyancy' either. But when evaluation motion, carrying capacity and stability of a vessel, weight and buoyancy distribution are far more critical than the overall displacement of the vessel, or its keel type.


+1


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## Chadfunk48

Reading this thread makes me want to throw my hands up, sell my mono, and buy a cat...


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## Jeff_H

Ah so, but cats are far more complex to discuss in terms of tracking and motion comfort, not to mention fur balls and puking, and catamarrans are even more so.


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## Chadfunk48

I agree, my cats motion comfort is really terrible. All the scratching and biting really ruins an otherwise nice day on the water.


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## BryceGTX

Jeff_H said:


> Sea Hunter,
> 
> I am glad that you clarified what you are thinking. At least as you are describing it, (i.e. "Reserve buoyancy is a hulls ability to carry a load over and above displacement".) that is not in keeping with the way yacht and ship designers use the term, "Reserve buoyancy". What you are describing rarely if ever is considered as a part of yacht design.


"Reserve of Buoyancy" is a term that come from time begin of yacht design. Sometimes shortened to reserve buoyancy. There are a number of chapters in this subject and the importance of reserve of buoyancy in yacht design. Here is a quote from page 12 of "Naval Architecture" printed 1877.

".. commonly used to express the volume and corresponding buoyancy of the part of the ship not immersed, but which may be made water tight.."

"The under water, or immersed, part of a ship contributes to the buoyancy; the out-of-water part the reserve of buoyancy, and the ratio between the two has a most important influence upon the safety of the ship against foundering at sea."

It sounds like Sea Hunter described it correctly.
Bryce


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## BryceGTX

Daily Alice said:


> Bryce,
> 
> I got as far as finding VMG, metacenter and CB for a boat, but how do you arrive at " the ratio of mass righting moment to hull righting moment"? I mean what do you need first, for data, and what formulas are you using? I ask because your approach seems useful. Isn't hull righting moment graphed over various heel angles (like from 0-30 deg.)? Anyway, I'm curious, thanks.


Sorry it took so long to answer. The boat is now out of the water for winter storeage. I hope to create a new thread discussing this subject this winter. I have simulations to support my assertions.

For me, it is the defining distinction between a rough water boat and a non-rough water boat. Light weight racers are the worst, heavy weight cruisers like the big Island Packets are the best. For me, it is part of the answer to the age old question of "blue water" capable and it is consistent with what the experienced sailors know already.

The reasons I developed my simulations and mathematics was to understand the significance of different weight boats of similar size.

The problem with righting moment diagrams is that they become useless once you put a boat on waves (in rough water). So you cannot predict from righting diagrams what boat is best in rough water. You cannot even predict what a boat will do in rough water from its righting diagram.

Two boats of similar size can have very close righting diagrams. However, one will be very comfortable in heavy seas and the other can be quite dangerous.
Bryce


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## elspru

Based on what I've read of this thread, 
Full keel boats are the best general use boats,
since they are great in shallow water, deep water, long journeys and in heavy weather. 

Fin keel boats are only for special cases, such as racers, powersailers and marinophiles.


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## mitiempo

elspru said:


> Based on what I've read of this thread,
> 
> Fin keel boats are only for special cases, such as racing, powersailers and marinophiles.


You might want to tell that to what is very likely the majority of successful ocean crossers, who have fin keel boats.


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## elspru

mitiempo said:


> You might want to tell that to what is very likely the majority of successful ocean crossers, who have fin keel boats.


crossing an ocean can be done with even a raft made of styrofoam, doesn't mean it's comfortable. 
a full keel is better in heavy weather, and large waves, as it's less likely to heel with the waves, and more likely to simply go straight.

Sure you can plot your courses to avoid storms, and only go in mild weather, but then you miss out on all that rollercoaster fun .


----------



## mgiguere

If you're a weekend sailor with a couple weeks vacation on the boat in the summer, (90% of us) then a well designed (S&S for example) fin keeled boat is far better. Faster, more maneuverable, less wetted surface, etc. Have had the boat 30 years, been off shore, as well--handles great.


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## elspru

I'm really glad you admited to being a weekend sailor, as that fits in my view of fin keelers . We intend to liveaboard, on the hook as much as possible, traveling to different areas harvesting resources, with a shoreside plot for backup, though indeed we could be a small minority, that's okay , oh ya ferrocement full keeler mmm, sooo good :-D.


----------



## fallard

After scanning this blog, it is apparent that there are a quite a few folks out there who are able to rationalize their positions on fin vs. full keel based on what they own. "Love me, love my boat." 

My current boat is is a 35' sloop with a weighted swing keel. It has other parts than the keel that impact its performance, like substantial form stability (less heeling) and inboard shrouds (allows better performance to upwind). It--like every boat--is a compromise and has its negatives, like less interior space to accommodate the keel trunk and more moving parts (swing keel and also a swing rudder). All of this allows the boat to float in less than 2' of water, but with drastically reduced maneuverability. I've sailed her from the Gulf coast to Maine over a period of 16 years and have found myself in a wide range of conditions and have to admit that I'm rather comfortable with the compromise. I've had her offshore and I've been in various conditions from light winds to sustained winds of 40+ kts. 

On the other hand, I've sailed on many full- and modified full-keel boats ranging from a 26' Dolphin to a 42' Island Packet over the past 40 years. Most of my experience on full keel boats was as a bareboat skipper for a minimum of a week at a time and a lot of that was in the Caribbean, from Puerto Rico to Antigua. These keel boats were noticeably less responsive than the fin keel boats I've sailed. This could make for a challenge when tacking, for example, especially with the cutter rigged Island Packets. They also didn't do as well going to weather or in light air. On the other hand, they were more comfortable when the wind picked up to 20+kts, but some of that was due to their higher displacement. For some reason, all of the Island Packets I've been on (350, 370,380, 40, 420) required a heavy hand to steer. This might have been due to the steering design, rather than the keel, but the net result was fatigue and sore shoulders, so whatever tracking advantage is claimed for full keel boats was nullified. When going to weather, I would just use the motor. The fin keel boats--mine included--took a much lighter touch on the wheel and were more weatherly. This is a big deal on longer trips or in higher winds.

The one serious reservation I have about fin keels is their deeper draft, which makes anchorages smaller and some "shortcuts" unavailable. 

There is no boat that does everything, so you pick your parameters and live with a compromise in either case. In my case, the swing keel and swing rudder needed an expensive upgrade (to make sure things move when necessary). These expenses would not be incurred with a traditional full keel (non-centerboard) boat. On the other hand, I have never needed help to get ungrounded.

My bottom line on fin vs. full keel is that to each his own.


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## flo617

I agree,

I have a cutaway forfefoot keel and while they turn on a dime when the wind is just right, they are sluggish at low speed and I have had a few problem tacking when the wind was really strong just like I had on cape cod mercurys so it's not just the shape.

I approach my boat rationaly, it's a machine with nice features and flaws too. It's a little disconcerting to see people swear by the design they happen to have (sometime by luck) and get into pissing contest about the shape of their keel. All this talk is nonsense, the only persons I would trust in this matter are boat designers and naval architects. Let them discuss the merits of such and such configuration. The rest is legend and fable.


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## PCP

flo617 said:


> I agree,
> 
> I have a cutaway forfefoot keel and while they turn on a dime when the wind is just right, they are sluggish at low speed and I have had a few problem tacking when the wind was really strong just like I had on cape cod mercurys so it's not just the shape.
> 
> I approach my boat rationaly, it's a machine with nice features and flaws too. It's a little disconcerting to see people swear by the design they happen to have (sometime by luck) and get into pissing contest about the shape of their keel. All this talk is nonsense, *the only persons I would trust in this matter are boat designers and naval architects. *Let them discuss the merits of such and such configuration. The rest is legend and fable.


Well, if you take it that way it is rather simple: Naval Architects, I mean reputable ones, have long abandoned full keel configuration even for blue water cruising purposes, even the ones that once, far in the past, designed full keel boats.

Regards

Paulo


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## flo617

And it might very well be.

Like I said, I do not feel like I belong to Team Long Keel just because it happens to be the design of my boat. Honestly the main reason I got a longer keel boat was because I felt that they would be mechanically better connected to the keel due to its length and because the other fin keeled boat I had surveyed had a little flexing problem there (it was an encapsulated keel)

Come to think of it now, with the experience I got on this one, that would probably have been repairable in a few week-ends but that's another story.

Bottom line is I could have gone for a fin keel.


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## fallard

One doesn't have to be a boat designer or naval architect to understand the mechanics and hydrodynamics of keels. There are lots of sailors who aren't naval architects, but have enough technical savvy to clearly understand the characteristics of different keel shapes. The keel is only one part of an assemblage of often interactive parts, so it can be presumptive to label a boat as a "full keel" or "fin keel" boat, as if that is sufficient to characterize the boat. 

Take the Island Packet (IP)cutters, for example. All the ones I've sailed had a modified full keel, but their shortfall in tacking related as much to getting the genoa through the narrow slot between the inner and outer forestays when coming about. The keel/rudder combination doesn't allow you to pivot through the wind as crisply as a fin keel/ spade rudder arrangement would. This problem would be mitigated if you had a sloop rig (as some IPs are configured). The IPs probably do better in higher winds because of that cutter rig vs. a higher sloop rig--not because they are full keel boats. 

That said, there is a loyal IP following, not necessarily because their customers are fond of a full keel, but because the total package fits their lifestyle. I have been going back to IPs for Caribbean charters because the IPs work for me in that venue. In southeastern New England, however, I am happy with my own boat for a variety of reasons--not just because is has a fin keel. 

If folks are passionate about their boats, so what? Putting down someone else's, however is another matter.


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## fallard

One doesn't have to be a boat designer or naval architect to understand the mechanics and hydrodynamics of keels. There are lots of sailors who aren't naval architects, but have enough technical savvy to clearly understand the characteristics of different keel shapes. The keel is only one part of an assemblage of often interactive parts, so it can be presumptive to label a boat as a "full keel" or "fin keel" boat, as if that is sufficient to characterize the boat. 

Take the Island Packet (IP)cutters, for example. All the ones I've sailed had a modified full keel, but their shortfall in tacking related as much to getting the genoa through the narrow slot between the inner and outer forestays when coming about. The keel/rudder combination doesn't allow you to pivot through the wind as crisply as a fin keel/ spade rudder arrangement would. This problem would be mitigated if you had a sloop rig (as some IPs are configured). The IPs probably do better in higher winds because of that cutter rig vs. a higher sloop rig--not because they are full keel boats. 

That said, there is a loyal IP following, not necessarily because their customers are fond of a full keel, but because the total package fits their lifestyle. I have been going back to IPs for Caribbean charters because the IPs work for me in that venue. In southeastern New England, however, I am happy with my own boat for a variety of reasons--not just because is has a fin keel. 

If folks are passionate about their boats, so what? Putting down someone else's, however is another matter.


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## chucklesR

I can't believe this went on for 50 pages. 

Apples, oranges - which is better?

I love the technical discussions, the opinions I take with a grain of salt (and then a shot of tequila).
Here's my opinion - 
On my Gemini (catamaran) with the boards up it was akin to a long shoal keel - 32 feet long, but only 18 inches deep - and it sucked to leeward, I mean drifted. Board down and it was 5/12 feet of asymmetrical lifting pointy-ness. 

On the Irwin 38 Mk II I have the shoal keel, 4.5 feet of stubby. I don't care about the extra 2 degrees of leeward drift in 5 knots of wind - because I'm probably going to be motoring in 5 knots
Once the boat gets to speed it points just fine. 
I don't care about the 3-5 degrees of extra point I might get out of a fin keel (6 foot, optional on the boat) - because I'm not racing for the buoy. 

I might care about the extra degrees on a 500 mile off shore leg but only because it will save me a half day on the trip. Then again so will being able to cross that sand bar without dragging or bouncing off the coral.


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## Faster

chucklesR said:


> I can't believe this went on for 50 pages.


Yes, amazing, isn't it??

And probably no converts either.. in any event it's been interesting, entertaining and vexing, all at the same time.

Compromise and setting priorities is what it's all about.. and always has been.


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## fallard

We could go for 51 pages.

Agree with Faster that its about compromise and priorities: rarely does a single parameter, like the keel, decide the matter. 

My wife was enamored of the Island Packets we have chartered from Florida to the Caribbean for quite a while. She liked the roomy cabins in particular and the large galley and all the storage. Our own boat, by comparison, has a narrow cabin and wide side decks and a keel trunk that splits the main cabin and runs all the way to the coachroof. Our storage is probably a third that of an IP of the same length (35').

Our boat has a retractable, weighted fin keel that allows us to go from 5'11" draft down to 1'10" (with keel and rudder retracted), but normally she is sailed with everything down until we come into a shallow anchorage or negotiate a "shortcut".

What really makes the difference worth it is that we can keep the boat at our shallow water dock, yet we can sail to weather better than most. In our area in southeastern New England, weatherliness matters when you are heading west against the typically southwesterly breeze. 

Well, we were beating from Cuttyhunk to Mystic (about 50 nm) several years ago when we passed a larger Island Packet that was motoring in the same direction. The IP skipper saw us, unfurled his sails, and took up the challenge. Unfortunately, he could not point as high and soon enough had to come about, unable to maintain a competitive velocity made good to Watch Hill Passage. He rolled up his sails and continued to motor. The difference was primarily the keel (full vs. my fin) and the fact that the IPs have outboard shrouds and don't allow sheeting the genoa as close. We made it on the same tack all the way to the Mystic River. My wife--who would rather sail and absolutely hates to motor--stopped bugging me about the IP accommodations after that. 

That said, we continued to charter IPs in the Caribbean, where she can enjoy the bigger cabins and larger water tanks (we like our showers at the end of the day). The longest legs we've motored are about 15 miles--she can put up with that. (You really don't want to sail a full keel boat from St. John to Virgin Gorda.)


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## MarkSF

fallard said:


> We could go for 51 pages.
> 
> Agree with Faster that its about compromise and priorities: rarely does a single parameter, like the keel, decide the matter.
> 
> My wife was enamored of the Island Packets we have chartered from Florida to the Caribbean for quite a while. She liked the roomy cabins in particular and the large galley and all the storage. Our own boat, by comparison, has a narrow cabin and wide side decks and a keel trunk that splits the main cabin and runs all the way to the coachroof. Our storage is probably a third that of an IP of the same length (35').
> 
> Our boat has a retractable, weighted fin keel that allows us to go from 5'11" draft down to 1'10" (with keel and rudder retracted), but normally she is sailed with everything down until we come into a shallow anchorage or negotiate a "shortcut".
> 
> What really makes the difference worth it is that we can keep the boat at our shallow water dock, yet we can sail to weather better than most. In our area in southeastern New England, weatherliness matters when you are heading west against the typically southwesterly breeze.
> 
> Well, we were beating from Cuttyhunk to Mystic (about 50 nm) several years ago when we passed a larger Island Packet that was motoring in the same direction. The IP skipper saw us, unfurled his sails, and took up the challenge. Unfortunately, he could not point as high and soon enough had to come about, unable to maintain a competitive velocity made good to Watch Hill Passage. He rolled up his sails and continued to motor. The difference was primarily the keel (full vs. my fin) and the fact that the IPs have outboard shrouds and don't allow sheeting the genoa as close. We made it on the same tack all the way to the Mystic River. My wife--who would rather sail and absolutely hates to motor--stopped bugging me about the IP accommodations after that.
> 
> That said, we continued to charter IPs in the Caribbean, where she can enjoy the bigger cabins and larger water tanks (we like our showers at the end of the day). The longest legs we've motored are about 15 miles--she can put up with that. (You really don't want to sail a full keel boat from St. John to Virgin Gorda.)


Is it a secret what kind of boat you have?


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## mitiempo

MarkSF said:


> Is it a secret what kind of boat you have?


Not a secret, it is listed on his profile.


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## BryceGTX

fallard said:


> What really makes the difference worth it is that we can keep the boat at our shallow water dock, yet we can sail to weather better than most. In our area in southeastern New England, weatherliness matters when you are heading west against the typically southwesterly breeze.


Apparently you put a high priority on only performance and shallow water capability. Not sure many including your wife likes the extremely restrictive cabin space of your boat.

We would find it unacceptable. Faced with the same choice, I might look at a cat or A seaward yacht. Or better yet.. Dock it elsewhere and get a boat your wife likes.

On the other hand, I am having trouble following your comparison to an IP. You compare it based on only performance. Let's put your boat and that big IP in tropical storm weather And see which one you prefer to be on.

Better yet.. Let's ask your wife..
Bryce


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## blt2ski

One of the LAST boats I would want to be on is an IP in higher winds......but that is me.

My wife would also prefer one a bit less cramped than what we have. BUT, even a full keeler would not have a lot more room. I was on boar an Eric jr awhile back. Half the room of my boat, with the same length etc. Not sure it would do any better in a blow either.

As said, one needs to decide WHICH keel will work best for that persons circumstances. Be it a fin, full, something in the middle, or for that matter, a CB style! Along with for kicks and giggles, lets throw in a canting keel with dagger boards! ie a V70 or equal style boat! Schock built a 40' canter for awhile.......you could probably still get one if you really wanted it!

At the end of the day, choose based on where you are going, how you wish to sail etc. For me, it would not be a full keel, not matter where I was going! IF I needed shoal draft, I would go with a CB or lifting keel of some sort. then put it down in deeper water for the additional pointing etc they offer over full keels. Then an appropriate hull form which is probably more important for comfort etc. than keel shape or form.

Marty


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## fallard

BryceGTX must have missed my point. We all make tradeoffs to suit our needs. The cabin layout and storage space of our Clearwater 35 is less than that of an IP 35/350 (and many other 35 footers) but it is not "extremely" restrictive. Unless you needed the shoal draft, you would likely pass it over for a boat with a more conventional layout. We wish we didn't get shoal draft at the expense of interior space, but that's life. We--that includes my wife--like our boat overall and after 16 years aren't about to trade it in.

Having the boat at our shallow water dock about 150' from my front door is a lot more convenient and a lot less expensive than keeping it at a marina. The reality is that there is limited choice in ocean-capable boats that can come to our dock at a normal low tide (2.5' @ MLW). The Shannon Shoalsailer, the smaller Southerlies, the Seawards might get to our dock most of the time, or maybe some of the smaller catamarans. But, since we get to see our boat every day in season, looks matter. The Clearwater 35 is arguably one of the prettiest shoal draft boats in this size range and that matters to us

Comparing the Clearwater to an IP is apples and oranges. A clear differentiator between our boat and an IP--other than the interior space--is sailing performance. My Clearwater 35, as with most well-designed fin keel boats in this size category, will outpoint the IPs. Coming home to Mystic from Nantucket, Martha's Vineyard, Cuttyhunk, or Newport, this is the difference between sailing and motoring. This is very important to us--particularly my wife, who hates to motor.

Another factor is that anchorages are bigger when your boat can float in 2' of water. Cuttyhunk is one example, where the shallow end of the rental pilings is 4' at low water. Also, there are Cuttyhunk town slips with less than 4' that are the last to be taken on a busy weekend. And don't forget the increased opportunity for gunkholing, like in Hadley's Harbor.

I've seen my share of high winds, but unless we are talking off the wind, I'll stick with my Clearwater, which is much easier to control than the IPs I've sailed. I attribute this to the keel/rudder configurations--with the fin keel providing more responsiveness when needed. When it come to safety below in a seaway, the more confined space in my Clearwater becomes an advantage. When it comes to tropical storm weather, you won't get me out there on any boat, including the Mirabella V.


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## chucklesR

So, 

What's the deal with the 'high performance wing keel' on the late 80's Irwin's ?

Is it possible to have a high performance shape in a 3 foot stub with wings?


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## Oregonian

Quote from BLT2SKI



> "My wife would also prefer one a bit less cramped than what we have. BUT, even a full keeler would not have a lot more room. I was on boar an Eric jr awhile back. Half the room of my boat, with the same length etc. Not sure it would do any better in a blow either."


Eric Jr. LOA= 25'2"; Beam= 7'7"; Draft= 4'

Jeanneau 30 LOA= 29'6"; Beam= 10'5"; Draft= 5'6"


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## fallard

To ChucklesR question about a late 80's 3ft' stub keel with a wing: First of all, the Australians created quite a stir with their wing keel in the America's Cup in the 80's and it seemed to create a marketing angle for some boatbuilders. There obviously was some merit, but there are several factors at play when translated to the recreational market.

First of all, the wing keel provides an end plate for the primary keel to reduce tip vortices--for the same reason you see winglets on the later versions of commercial jets--to reduce drag. Also, adding the wing shape produces a fatter (i.e., heavier) "bulb" to provide more of a righting moment for a given keel length.

That said, you may notice that the more efficient racing keels are like glider wings: deep, high aspect foils. The downside is the deep draft required to pursue this approach.

But, getting back to ChucklesR's Irwin, it's all about a real world compromise. A short stub keel is not going to provide the lift of a longer, high aspect foil, but, by adding the wing (for added ballast) it can offer reduced draft.

Oh, by the way, a full keel is the antithesis of an efficient, high aspect keel, for those who care to think about keel compromises. You might look to aircraft design for a reference point. The only aircraft I can think of with low aspect wings are "wing-in-ground" (WIG) craft, like the one built by Merrifield Roberts in Rhode Island about 20 years ago or the huge, "Caspian Sea Monsters" built by the Soviets several decades ago. That said, I am not a hydrodynamicist or naval architect/boatbuilder, so you can take my comments with a grain of salt.


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## VK540

Jeff_H said:


> I do think that there is something wrong with his statement beyond being incomplete and that you are mistaken when you say that _"the rotation of the water in a wave causes the full keel boat to heel toward the wave rather than heel with the wave as with other keel designs."_
> 
> Perhaps I can explain the basis of my comments and we might be able to reach agreement.
> 
> I will start with the first quote by Pvajko:
> _"The most important reason is that a full keel with its bigger surface area damps the rolling motion better." _
> 
> Here is the problem with that statement, dampening (the ability of a boat to dynamically to resist rotational motion) is directly proportional to a moment of inertia the amount of which results from the resistive force of the rotation and the distance that resistive force is from the instanteous rotational axis. In calculating a dampening moment, the force is a linear factor, but distance from the center of that force to the instanteous rotational axis is to the third power.
> 
> So that when you talk about the amount of dampening moment generated by a specific keel or keel type, the amount of area of the keel is a certainly significant factor, but the distance between the center of its rotational resistance and the instanteous rotational axis can be even more significant.
> 
> So, if we talk about the fin keels in the era when 'Seaworthiness' was written, these keels had perhaps a quarter of the surface area of a full keel on a similar length boat (and here I am not talking about the boats with long overhangs, an extreme cut away forefoot and raked rudder posts which had little more area than fin keels with separate rudders).
> 
> In the era that Marchaj wrote his book, between the shape of the fin keel, and the vertical height of the instanteous roll axis on fin keel boats of that era, the distance between the center of its rotational resistance and the instanteous roll axis was similar between a fin keel boat and a full keel boat and so the greater area of a full keel meant that there was significantly more dampening generated which is what Marchaj concludes.
> 
> But in the years since, several things have changed. Modern fin keel boat have greater draft, and differently shaped keels so that a greater portion of their area is deeper in the water, and their hull forms are such that their roll centers are slightly higher. That combination means that there can easily be a several time greater lever arm between the center of rotational resistance and the instanteous roll axis. So if we think that a modern keel has perhaps 20% of the area of a full keel but 2 or 3 times greater lever arm taken to the third power (in other words something like 8 to 27 times more leverage) it is easy to see that a modern fin keel boat could easily develop much higher dampening moments and so have better dampening than a full keel boat, making Pvajko statement incorrect that _"The most important reason is that a full keel with its bigger surface area damps the rolling motion better." _
> 
> In terms of Pvajko statement: _"While a fin keel performs much better in ideal conditions (flat water), stormy weather with big seas is a whole different story."_
> 
> I might agree with you that this is in part a true statement. All keels generate more lift in flat water than they do in disturbed conditions, but since fin keels tend to stall out much more quickly than longer chord keels, they lose a larger percentage of their lift, in other words, "stormy weather with big seas is a whole different story" for all keels but especially for fin keels.
> 
> But here is where that statement is misleading, in the years since 'Seaworthiness' the better modern fin keel shapes and corss sections have been developed to perform across broader range of conditions while losing a smaller percentage of their performance advantage. The impact of better dampening, the endplate effect of the bulb, foil shapes which more quickly establish flow and respond to it, means that fin keel boats may lose some small amount of their advantage over full keels in heavy going, depending on the course relative to the waves(i.e.beating upwind), but the modern fin keels still retain a significant performance and motion comfort advantage over a traditional full keel of similar length and displacement.
> 
> This last sentence is where it gets tough to make an 'apples to apples' comparison. In a broad general sense, full keeled boats tend to be heavier for their length (I know this is a 'duh statement) and have different hull forms than most modern fin keel boat. Because of that disparity it is easy to ascribe attributes to a full or fin keel which have nothing to do with the keel type and everything to do with the boat's design as a system. But even taking that into account, the statement seems to imply that a boat with a full keel will out perform a fin keel boat in heavy conditions, and while that may be true for some fin keels vs. full keels, it is not a universally accurate statement.
> 
> Regarding your statement: _"It has been well documented in 100 year old yacht design books that full keels have the advantage in big water because the rotation of the water in the wave causes the full keel boat to heel toward the wave rather than heel with the wave as with other keel designs."_
> 
> I personally don't know of any 100 year old yacht design book that says anything like that, but when I go back and look at my earliest copy of Skene's and Kunhardt, I find no reference of the sort so it might be helpful if you could provide a source for that. But even so, the idea that full keels heel toward a wave while fin keels rolls away flies in the face of what is known about the motion of boats in big waves.
> 
> What the science would suggest is that there are a number of factors which determine whether a boat heels into a big wave or away from the wave. First of all there is the rotational force. If you dissect the surface of a large wave, the water at the surface is moving faster than the water deeper in the wave nearer to the wave center. This progressive difference in speed between the surface and the center of the wave, means that the deeper the keel, the greater the sheer in the water speed acting on the boat trying to rotate the boat so that it heels away from the surface of the wave. Similarly, a keel with a greater side area will experience greater rotational force and so will have a greater tendency to heel away from the surface of the wave. But also, fin keels stall at very steep angles of attack, as might be experienced beam to on the side of big wave, thereby reducing the side force per unit area that the deeper keel may experience. This combination of factors means that in any specific case, either a fin keel or a full keel could experience the greater rotational force.
> 
> Resisting the roll force are stability and the roll moment of inertia. In the case of the fin keel vs. full keel discussion, modern fin keels, with their deeper drafts and densely concentrated ballast bulbs, generally generate much higher proportional stability than full keels. That was not the case at the time when 'Seaworthiness' was written but since modern designers have paid attention to the lessons of seaworthiness, and modern racing rules do not penalize stability as much as they did back then, it is true on the better modern fin keeled designs of today.
> 
> This greater stability means that a modern design would generate proportionately greater force to keep them upright and therefore greater force trying to heel the deck back toward the wave face.
> 
> The other factor, roll moment of inertia is similar to the discussion on dampening. The two factors impacting the amount of roll moment of inertia is weight and the distance between that weight and the instantaneous roll axis. While modern fin keeled boats tend to be lighter, they also tend to be deeper and taller so that due to their weigh distributions, they develop a disproportionately large roll moments of inertia.
> 
> In big waves, a large roll moment of inertia does two things, at the top of the wave, it delays the rotation of the boat relative to the rotational force. A good thing, but at the bottom of the wave, its greater stored kinetic energy, tends to cause it to get out of phase with angle of the wave face and continue to roll as the bottom of the wave flattens out so that there is a greater danger of dipping a spar in the water (never a good thing).
> 
> But to look at your statement fairly, we might also look at factors that have nothing to do with keel type. Modern designs tend to have greater form stability. Greater form stability tries to keep the waterline of the boat parallel to the wave face. At the top and middle of the wave, that would tend to roll the deck of the boat away from the face of the wave, the behavior that you describe in your quote. But that has nothing to do with the keel type. Two boats of equal form stability, similar draft and ballast stability, and roll moment of inertia would have the same angle of heel whether the boat had a full or fin keel.
> 
> And lastly, at the bottom of the wave, the boat with greater form stability would generate more righting force, remaining in sync with the wave surface and so would be less likely to dip a deck or spar and keep rolling.
> 
> What all of this suggests is that the specifics of the boat design and the conditions will determine whether it heels relative to the wave surface, but that the use of a fin keel or full keel is but one minor factor.
> 
> Strictly speaking that is not always or even usually correct as it is written. While it is easier to keep the weight lower in a longer keel of an equal draft. But modern fin keels generally are deeper and have a bulb which makes it easier for them to carry their ballast with its vertical center lower than most full keels. But also there are a lot of factors that make a boat 'forgiving'. A modern fin keel boats relatively greater stability, lighter helm loads, more forgiving rig and sail handling gear, and more easily driven hull form might work in its favor 'forgivingness' wise. The typically better directional stability and lower vertical center of effort work in the favor of a typical full keel boats 'forgivingness'.
> 
> Respectfully,
> Jeff


Holy WOW! I hope Smack takes some of Jeff's posts and slips them over to the "Old Salts" thread from this post!


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## skygazer

Jeff_H said:


> ........And lastly, at the bottom of the wave,* the boat with greater form stability would generate more righting force, remaining in sync with the wave surface *and so would be less likely to dip a deck or spar and keep rolling.
> 
> What all of this suggests is that the specifics of the boat design and the conditions will determine whether it heels relative to the wave surface, but that the use of a fin keel or full keel is but one minor factor.........
> 
> Respectfully,
> Jeff


I always enjoy Jeff's informative and thought provoking discussions.

If I'm understanding this correctly, the modern boat remains in sync with the wave surface by generating more righting force (due to it's flatter wider shape). The greater righting force is also generating more rapid and continuous (rotational) acceleration. This greater acceleration would be more exhausting to the human occupants.


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## Jeff_H

skygazer said:


> I always enjoy Jeff's informative and thought provoking discussions.
> 
> If I'm understanding this correctly, the modern boat remains in sync with the wave surface by generating more righting force (due to it's flatter wider shape). The greater righting force is also generating more rapid and continuous (rotational) acceleration. This greater acceleration would be more exhausting to the human occupants.


First of all thank you for the kind words. To address your comment, to some extent you are correct that that a boat with greater form stability will stay in sync with the wave face, and in some conditions will be less comfortable and tiring for the occupants. But the the reality of whether the boat is more comfortable to the occupant is also dependent on other factors.

So for example, depending on wave size, steepness and frequency, on the boat with less form stability, the delay in the change in direction may be such that the boat actually continues moving past the point the wave shape changes at the crest or trough. In those conditions, being out of sync. the boat experiences a harder impact with the wave surface and so actually experiences a harsher deacceleration than the boat with more form stability, and so can be harder on the occupants.

Mitigating against the harshness of the motion, dampening from the keel and rig can greatly improve rotational motion comfort, slowing changes in direction without adding the kind of inertia, which tends to make the boat more dramatically over shoot the wave face and so experience grater impact forces.

And this is where the specifics of the design come into play. Too much form stability and the boat will throw its occupants around mercilessly. Too little form stability and the boat will roll and pitch the occupants to death. Which is why I personally advocate a more moderate design philosophy than seems to be the case with the more extreme current design practices.

Coming back to the Full keel vs Fin topic, this another area where the specifics of the design come into play. A full keel would tend to have a comparatively large area which helps to increase dampening force thereby slowing roll rates, but full keels a shallower draft which works against creating as large a dampening moment. So depending on the design, a deep fin, although generating less sideforce, may in fact generate an equal or greater dampening force.

Jeff


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## chucklesR

Ted Brewer's Motion Comfort Ratio might be germane:
MCR = Disp / (2/3*((7/10 * LWL)+(1/3 *LOA))*Beam4/3 )

Now for me that's a little too much math so I go here The roll acceleration: What´s the best for crossing oceans? - Boat Design Forums 
and look up a boat. Unfortunately mine is not listed.

Note the formula does not take in keel shape at all - a surprising lack considering the effect of lift and weight, moment arms and all that other 'stuff' that has kept this thread growing. 
Of course it also shows Brewer designs as being seriously comfortable.

I also can't see where LOA comes in - my bow spit adds nothing to comfort - that should be LO deck.


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## Jeff_H

(I apologize in advance for the cut and paste of something I wrote a long time ago)

The Capsize Screen Formula and the Motion Comfort Index tells almost nothing about how the reality of a boat's likelihood of capsize or its motion comfort. In fact they provide so little indication of a boat's behavior that to rely on these surrogate forumlas for real information borders on the dangerous.

Both of these formulas were developed at a time when boats were a lot more similar to each other than they are today. These formulas have limited utility in comparing boats other than those which are very similar in weight and buoyancy distribution to each other. Neither formula contains almost any of the real factors that control motion comfort, the likelihood of capsize, or seaworthiness. Neither formula contains such critical factors as the vertical center of gravity or buoyancy, neither contains weight or buoyancy distribution (of the hull both below and above the waterline), the extent to which the beam of the boat is carried fore and aft, and neither contains any data on dampening, all of which really are the major factors that control motion comfort or the likelihood of capsize.

I typically give this example to explain just how useless and dangerously misleading these formulas can be. If we had two boats that were virtually identical except that one had a 500 pound weight at the top of the mast. (Yes, I know that no one would install a 500 lb weight at the top of the mast.) The boat with the weight up its mast would appear to be less prone to capsize under the capsize screen formula, and would appear to be more comfortable under the Motion Comfort ratio. Nothing would be further than the truth.

And while this example would clearly appear to be so extreme as to be worthy of dismissal, in reality, if you had two boats, one with a very heavy interior, shoal draft, its beam carried towards the ends of the boat near the deck line, a heavy deck and cabin, perhaps with traditional teak decks and bulwarks, a very heavy rig, heavy deck hardware, a hard bottomed dingy stored on its cabin top, and the resultant comparatively small ballast ratio made up of low density ballast. And if we compare that to a boat that is lighter overall, but it has a deep draft keel, with a higher ballast ratio, the bulk of the ballast carried in a bulb, its maximum beam carried to a single point in the deck so that there was less deck area near the maximum beam, a lighter weight hull, deck and interior as well as a lighter, but taller rig, it would be easy to see that the second boat would potentially have less of a likelihood of being capsized, and it is likely that the second boat would roll and pitch through a smaller angle, and would probably have better dampening and so roll and pitch at a similar rate to the heavier boat, in other words offer a better motion comfort....And yet, under the Capsize Screen Formula and the Motion Comfort Index it would appear that the first boat would be less prone to capsize and have a better motion when obviously this would not be the case.

There are some better indicators of a vessel's likelihood of capsize. The EU developed their own stability index called STIX, a series of formulas which considered a wide range of factors and provides a reasonable sense of how a boat might perform in extreme conditions. Unfortunately meaningful results require a lot more information than most folks have access to for any specific design. The Offshore Committee of US Sailing developed the following simplified formula for estimating the Angle of Vanishing Stability (Sometimes referred to as the 'AVS', 'limit of positive stability', 'LPS', or 'Latent Stability Angle' ):
Screening Stability Value ( SSV ) = ( Beam 2 ) / ( BR * HD * DV 1/3 )
Where; 
BR: Ballast Ratio ( Keel Weight / Total Weight )
HD: Hull Draft 
DV: The Displacement Volume in cubic meters. DV is entered as pounds of displacement on the webpage and converted to cubic meters by the formula: 
Displacement Volume in Cubic Meters = ( Weight in Pounds / 64 )*0.0283168
The Beam and Hull Draft in this formula are in meters. These values are entered in feet on the webpage and are converted to meters before SSV calculation.
Angle of Vanishing Stability approximately equals 110 + ( 400 / (SSV-10) )

There is a convenient calculator at http://www.sailingusa.info/formula.htm

It should be noted that the AVS is only one indicator in evaluating the likelihood of capsize, meaning it only predicts the point at which the vessel wants to turn turtle. It does not predict the amount of force that would be required to heel the vessel to that limit, nor does it predict how the shape of the boat might encourage wave action to roll the boat closer to the angle at which it no longer wants to return.


----------



## chucklesR

> The Capsize Screen Formula and the Motion Comfort Index tells almost nothing about how the reality of a boat's likelihood of capsize or its motion comfort. In fact they provide so little indication of a boat's behavior that to rely on these surrogate forumlas for real information borders on the dangerous.


I agree 100%

On the AVS - you still need to add righting moment curves, accurate displacement and center of gravity. 
It's still a best quesstimate.

My big bulwark, fully enclosed center cockpit, thin (12.3 beam on a 38ft) 4.5 foot draft, Low density (lead pigs in slurry) stubby ballast should roll over if I stand on a rail. Especially considering the 300 feet of chain and 45 pound anchor, Dinghy on the davits and other weight high up (my big head) etc..
I think adding on a couple square yards of solar panels should do it.

Unfortunately the link doesn't work.


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## zeehag

people can yap all they want to about different keels and styles o boat. it is going to be a huge investment--time, money and lifestyle--why dont you take a sail on each kind of boat that interests you--as opb cruising or racing--see what YOU like best an buy that????
in order to know what YOU like to sail, you have to sail it .....have fun--is the most funnest part of boat purchasing--research!!!!

btw--we dont need no stinkin numbers--when passion hits, BUY.


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## skygazer

zeehag said:


> btw--we dont need no stinkin numbers--when passion hits, BUY.


Well said!! Love your attitude!

Much as I like science and understanding - art, music and passion are really what matters to me! I've never tried a boat before I bought it, probably because I buy cheap wrecks for a song that need work before launching. Always it's the older traditional styles that grab me when I see them sitting beside the road. But this year I bought a Hunter 23 (a wreck). Partly because of this thread, and partly because it was there. A super ugly stubby wing keeled boat, which I hate to look at and always think "toy boat". I must admit, it sails surprisingly well. And, when I'm on it, I can't see how ugly it looks, I just sail around the beautiful traditional boats and look at them.  With a theoretical hull speed of something like 5.9 knots, I was surprised when my new (tiny, pocket sized hiking style) first GPS showed I was doing 6.2 MPH (not knots) going against the tide while tacking into the wind. Recently I found that it recorded tracks of where I went, and showed my top speed to be 8.3 MPH. I can only think I must have been surfing down some monster waves going with the wind and tide. (Week long sail/anchor.) Of course, when I'm ripping along, I don't bother changing screens on the GPS to see my speed, too busy sailing! So I've enjoyed my first "modern" boat more than I expected. Except looking at it.


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## BryceGTX

blt2ski said:


> One of the LAST boats I would want to be on is an IP in higher winds......but that is me.
> Marty


200 years of yacht Architects would vehemently disagree with you. The IP is not as wide as most big cruisers, and coupled with the full keel tends to make the hull less stiff. As we all know the lower the stiffness, the better the rough water capability.

The huge keel mass coupled with the heavy hull results in a quite low CG further enhancing its rough water capability. And as everyone knows the IP is extremely respected in its rough water capability.

Bryce


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## PCP

BryceGTX said:


> 200 years of yacht Architects would vehemently disagree with you. ... As we all know the lower the stiffness, the better the rough water capability.
> 
> ...
> Bryce


Yes of course, all naval architects now that a tender boat is safer than a stiff boat on rough water, I mean sailing...

Regards

Paulo


----------



## BryceGTX

fallard said:


> BryceGTX must have missed my point. We all make tradeoffs to suit our needs.


Your boat was designed entirely as a performance shallow water boat. That means at all costs, even salon room was compromised to performance. That huge divider running directly down the center line of the boat from the steps to the forward bulkhead, from deck to ceiling, over a foot wide is a serious compromise.

So now you have a shallow water boat. Lets compare the shallow water performance to the IP. A particular IP has a draft of 4 feet. To put your boat in the same shallow water requires you to place your keel only half down. So now you keel is at 4 feet.

Problem is, only half of your keel is in the water. This means, only half of your lee resistance is provided. And of course only half of your keel weight is where is suppose to be. The other half of the weight is inside your salon uselessly creating a heeling moment.

The IP owner would have to remove his keel and place it on his salon floor to get the same effect as your boat in this configuration. So clearly, when we compare the performance of your boat in the same shalllow water you are at a serious disadvantage.

You complained that the IP is hard to tack because of its dual headsail configuration. However, its inner jib is invariably a self tacking jib. In situations where constant tacks are required why use the outer jib? In that case the IP owner has it all over your boat. He just turns his wheel.

My argument with you is not that your boat does not head to wind just fine. But you thoughtfully left out all the other advantages of the IP over your boat.

Bryce


----------



## BryceGTX

PCP said:


> Yes of course, all naval architects now that a tender boat is safer than a stiff boat on rough water, I mean sailing...
> 
> Regards
> 
> Paulo


Glad you are continuing to learn something from me. As we all know, a stiff boat follows the waves due to its significant hull moment, creating poor movement. Perhaps you need to review and learn from my previous posts. But to quote a book written 150 years ago:

A manual of Naval Architechture, 1877

"A stiff ship is... A steady ship on the contrary when exposed to the action of waves keeps nearly upright. the stiffest ships are the least steady."

Paulo.. I have pointed this out before. The characteristics of a rough water boat is it reamains vertical in the presence of waves. This is the characteristic of the IP.
Bryce


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## PCP

BryceGTX said:


> Glad you are continuing to learn something from me. ... But to quote a book written 150 years ago:
> 
> A manual of Naval Architechture, 1877
> 
> "A stiff ship is... A steady ship on the contrary when exposed to the action of waves keeps nearly upright. the stiffest ships are the least steady."
> 
> ...
> Bryce


I hope you start reading more recent books, you need it. XXI century sailboats boats have little in common with XIX century boats

Regards

Paulo


----------



## BryceGTX

Jeff_H said:


> Mitigating against the harshness of the motion, dampening from the keel and rig can greatly improve rotational motion comfort, slowing changes in direction without adding the kind of inertia, which tends to make the boat more dramatically over shoot the wave face and so experience grater impact forces.
> 
> And this is where the specifics of the design come into play. Too much form stability and the boat will throw its occupants around mercilessly. Too little form stability and the boat will roll and pitch the occupants to death. Which is why I personally advocate a more moderate design philosophy than seems to be the case with the more extreme current design practices.
> 
> Coming back to the Full keel vs Fin topic, this another area where the specifics of the design come into play. A full keel would tend to have a comparatively large area which helps to increase dampening force thereby slowing roll rates, but full keels a shallower draft which works against creating as large a dampening moment. So depending on the design, a deep fin, although generating less sideforce, may in fact generate an equal or greater dampening force.
> 
> Jeff


Jeff, you are thinking way too simplistically. We had a short discussion earlier in this thread. A significant problem with the long keel is that the force generated by movement of the keel stops being a damping component, but instead changes the dynamic center.

So you cannot say that the damping increases as some power, because at some point it is no longer damping. In large waves, the long keel on a boat with large hull moment can actually cause the boat to heel more because the dynamic center may drop below the CG of the boat.

So invariably, the shallow long keel often provides the better damping for a heavy boat. When I create my thread this will become clear.

There is no boat with wide beam and long keel will result in a good rough water boat. This has been pounded into yacht designers since time begin. Unless you put a coresponding heavy ballast to counteract the hull moment. But then it simply changes the mass moment to hull moment ratio which is what I suggest using as a rough water indicator; for lack of a better term, Bryces rough water coefficient.

Bryce


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## BryceGTX

PCP said:


> I hope you start reading more recent books, you need it. XXI century sailboats boats have little in common with XIX century boats
> 
> Regards
> 
> Paulo


If that were true, perhaps you can provide a quote from a newer book refuting my statement. My newer books support my statement. However for those that want to understand the mechanics, it is much more clearly explained in the older books.

The other point I wish to pound into peoples minds is that everything we are discussing has been discussed for centries. Even moveable balllast (which current racers think is so cool except they uselessly place it on the keel) was used in every racing boat prior to 1850 when it was outlawed by racing rules.

Bryce


----------



## PCP

BryceGTX said:


> If that were true, perhaps you can provide a quote from a newer book refuting my statement. My newer books support my statement. However for those that want to understand the mechanics, it is much more clearly explained in the older books.
> 
> The other point I wish to pound into peoples minds is that everything we are discussing has been discussed for centries. Even moveable balllast (which current racers think is so cool except they uselessly place it on the keel) was used in every racing boat prior to 1850 when it was outlawed by racing rules.
> 
> Bryce


Like in other subjects your opinions are so twisted that I refuse to discuss them with you and I wonder how many people really believe you know what you are talking about.

It is common knowledge that a stiff boat is safer in bad weather and this is not only a subject NA knows about, any good sailor with experience with stiff and tender boats in bad weather will know that.

A sailboat is not a motorboat that bobs around in waves and in bad weather will be strongly "tied" to a side by the force of wind on its sails. A stiffer boat will have more stability and a superior RM than a tender boat, can carry more sail in bad weather and will be "tied" much strongly to one side than a tender boat that will tend to bob around with the waves.

You don't need a book to know this; you have only to experience it.

Regards

Paulo


----------



## skygazer

PCP said:


> I hope you start reading more recent books, you need it. XXI century sailboats boats have little in common with XIX century boats
> 
> Regards
> 
> Paulo


In a "more recent' book, I read that fore and aft rigs were preferred for coastal sailing because they were more weatherly. But I was surprised to read that square sails were actually preferred for offshore work - faster and far more comfortable on long fair wind passages, without the danger of a gybe. Further, in light winds with large seas the fore and aft sails tended to slam from side to side. The schooner Kineo used up 14 sails on one long passage in 1905.

I hadn't realized that square sails were ever preferred, I thought fore and aft were far superior in all ways. That helps explain the mystery (to me) of ships with fore and aft mainsails and square topsails.


----------



## BryceGTX

PCP said:


> A sailboat is not a motorboat that bobs around in waves and in bad weather will be strongly "tied" to a side by the force of wind on its sails. You don't need a book to know this; you have only to experience it.
> 
> Regards
> 
> Paulo


A typical powerboat is considerably stiffer than a sailboat of similar size. And that is exactly why they are worse on rough water than a good rough water sail boat. Again, common knowledge.

Just so everyone knows, the stiffness of a boat is invariably determined primarly by the hull. A wider hull invariably creates a stiffer boat. Adding weight adds some stiffness, but nothing to that which can be had by modifying the hull. A wide flat power boat creates exactly such a stiff boat. And given that it carries its width longer than a sailboat, it inherently has more stiffness. The power boat has the problem that its CG is invariably above the waterline. This causes the CG to actually create a heeling moment. Which explains why some power boats can appear less stiff.

The stiffest sailboats are catamarans. They carry the beam to extreme resulting in a huge hull moment. And as we know, cats do not heel like monohulls. As a result can be very fast.

You seem to be confusing performance with rough water capability and those with experience know that rough water boats are different from performance boats. As far as I am concerned, this is widely held common knowledge.

The force of the wind on the sail has nothing to do with stiffness of the hull. I suggest you pick up a book and convince yourself. That is not to say a sail does not help stabilize the boat.
Bryce


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## BryceGTX

PCP said:


> A stiffer boat will have more stability and a superior RM than a tender boat,
> Paulo


I have also pointed out that the use of a stability diagram on a boat in a wave results in totally the wrong conclusion.

Keep in mind that the values in the stability diagram are the related to the bouyancy type force and the weight acting through the center of gravity. The force acting through the center of gravity always acts vertically. But the bouyancy force acts perpindicular to the water.

As long as the water is horizonal, the effective bouyancy force acts vertically and the weight vector acts vertically. In this case, the righting moment diagram is correct. However, when you place the boat on a wave, the effective bouyancy force acts at an angle equal to the wave angle. But the weight still acts vertically. This dramatically reduces the righting moment. There are additional secondary effects that further reduce the righting moment.

Furthermore, when we consider the dynamic effects, the axis of rotation is no longer at the metacenter. This has profound effects on how the boat heels. Some people want to analyze the dynamics as if the dynamic axis is at the metacenter. This is a severe error, particularly as the boat goes onto a wave. In the most extreme case, the dynamic center falls below the center of gravity.

So basically, we need to throw the stability diagram and metacenter out the window when we have dynamics or when we place the boat on waves. On the other hand that is why they call it the STATIC stability diagram.
Bryce


----------



## PCP

BryceGTX said:


> I have also pointed out that the use of a stability diagram on a boat in a wave results in totally the wrong conclusion.
> 
> Keep in mind that the values in the stability diagram are the related to the bouyancy type force and the weight acting through the center of gravity. The force acting through the center of gravity always acts vertically. But the bouyancy force acts perpindicular to the water.
> 
> As long as the water is horizonal, the effective bouyancy force acts vertically and the weight vector acts vertically. In this case, the righting moment diagram is correct. However, when you place the boat on a wave, the effective bouyancy force acts at an angle equal to the wave angle. But the weight still acts vertically. This dramatically reduces the righting moment. There are additional secondary effects that further reduce the righting moment.
> 
> Furthermore, when we consider the dynamic effects, the axis of rotation is no longer at the metacenter. This has profound effects on how the boat heels. Some people want to analyze the dynamics as if the dynamic axis is at the metacenter. This is a severe error, particularly as the boat goes onto a wave. In the most extreme case, the dynamic center falls below the center of gravity.
> 
> So basically, we need to throw the stability diagram and metacenter out the window when we have dynamics or when we place the boat on waves. On the other hand that is why they call it the STATIC stability diagram.
> Bryce


Well, you are wrong and it is not needed any complicated explanation to show that. Your explanations should adapt to reality and not the other way around.

Just have a look at two boats, with similar types of hulls, about the same size, one with 4.5T and a substantial part of its weight down on a bulb at the end of a 3m draft, the other one with 9T with much more proportion of weight in its hull and 1.55m of draft. Both are well designed boats the total RM would not be very different (due to the much bigger mass of the heavier boat) and the lighter boat will be massively stiffer.

We are talking here about a 40 class racer and about an Oceanis 41. Go to an experienced sailor that know both boats and tell him that the Oceanis is more seaworthy because it is a tender boat with a bigger mass and the guy will start to laugh. When he understands that you are not kidding he can go away shaking his head or if he his a patient guy will try to explain to you that the 40 class racer was designed to race solo on the Ocean on the worst conditions, that several, while circumnavigating higher than the furious 40's were caught in big storms and that all survived with flying colors. He may also say to you that the Oceanis is not designed to be sailed on high latitudes and that taking one there would not be a very smart thing to do.

He could also point out that even if the 40class boat is a racing boat, because the boat is fast and has a huge safety margin, older boats that are not competitive anymore are being bought by cruisers to circumnavigate with their families and that in this moment there are several doing that without any problem.

Regards

Paulo


----------



## BryceGTX

PCP said:


> We are talking here about a 40 class racer and about an Oceanis 41. Go to an experienced sailor that know both boats and tell him that the Oceanis is more seaworthy because it is a tender boat with a bigger mass and the guy will start to laugh. Regards
> 
> Paulo


LOL.. I will laugh also. I never said a tender boat is more seaworthy. You inferred it. I said that a stiff boat was not Steady. These are radically different concepts.

A steady boat has a large mass moment and less stiffness than a stiff race boat. It is exactly the huge mass and lower stiffness that makes it steady. On the other hand the simple example you pointed out shows that a more tender boat is not necessarily seaworthy nor steady. On the other hand, a steady boat is more tender than a stiff boat. You confused that all tender boats are also steady.

On the other hand, not sure I would call the Oceanis tender. It just is not as stiff as a racer. And It is not a rough water boat as I have pointed out in the past. And in no shape or form is a stiff racer a rough water boat.

But its good that you pointed this out. Others may have also missed the point.
Bryce


----------



## PCP

BryceGTX said:


> LOL.. I will laugh also. I never said a tender boat is more seaworthy. You inferred it. I said that a stiff boat was not Steady. These are radically different concepts.
> 
> ....
> But its good that you pointed this out. Others may have also missed the point.
> Bryce


Well your logic seems not right to me. You said:



BryceGTX said:


> ...
> 
> "*... A steady ship on the contrary when exposed to the action of waves keeps nearly upright. the stiffest ships are the least steady."
> *
> .... *the characteristics of a rough water boat is it reamains vertical in the presence of waves. This is the characteristic of the IP.*
> Bryce


You have said that a rough water boat should remains vertical in the presence of waves, that a steady ship when exposed to the action of waves keeps nearly upright and that a stiffest ship are the least steady.

So by your words stiffness is prejudicial to a boat regarding to remain vertical when exposed to the action of the waves (steady). You say also that the characteristics of a rough water boat is to remain vertical in the presence of waves. Therefore, according to you, as the stiffness of a boat increases it decreases its capacity to stay vertical in the presence of waves and that is the characteristics that you say that make the boat a rough water boat. So a stiffer boat will be a worse rough water boat.

It seems clear that the main quality of a rough water boat is its seaworthiness.

I never said that the Oceanis is a tender boat I said that the *40class racer is massively more stiff **and by your reasoning, since both boats share the same kind of hull, the Class40 should be less of a rough water boat (less seaworthy) than the Oceanis since the" stiffest ships are the least steady" and are, according to you ,the worst in what regards to stay vertical (steady) under the action of waves, the condition that you find more important to a rough water boat.*

Acording with what you say, the Oceanis, that is a lot less stiff, should be a better rough water boat than the 40class racer. It is not, not even close, there is a huge difference. The Class40 is a true bluewater boat capable of sailing in high latitudes and really heavy weather and that is not the case with the Oceanis. Therefore all your reasoning is wrong.

Regards

Paulo


----------



## BryceGTX

PCP said:


> Just have a look at two boats, with similar types of hulls, about the same size, one with 4.5T and a substantial part of its weight down on a bulb at the end of a 3m draft, the other one with 9T with much more proportion of weight in its hull and 1.55m of draft. Both are well designed boats the total RM would not be very different (due to the much bigger mass of the heavier boat) and the lighter boat will be massively stiffer.





PCP said:


> *40class racer is massively more stiff *
> 
> Acording with what you say, the Oceanis, that is a lot less stiff, should be a better rough water boat than the 40class racer. It is not, not even close, there is a huge difference. The Class40 is a true bluewater boat capable of sailing in high latitudes and really heavy weather and that is not the case with the Oceanis. Therefore all your reasoning is wrong.
> 
> Paulo


Ok.. lets see if you can back up your statements. The first place to start is to look at the stiffness. Since you say one is more stiff than the other.

What is the stiffness of each boat?
Bryce


----------



## PCP

BryceGTX said:


> Ok.. lets see if you can back up your statements. The first place to start is to look at the stiffness. Since you say one is more stiff than the other.
> 
> What is the stiffness of each boat?
> Bryce


I say that one is more stiff than the other? You have any doubt?

The stifness of a boat is directly related with the boat displacement and the sail area the boat can carry (SA/D). You can see that big difference yourself. The data on both boats is on the net.

I appreciate your effort to understand and relate seaworthiness and stability with mathematic formulas but on your efforts you start from the wrong basis:

Instead of assuming that boat design did not evolve in the last 50 years, as well as the way seaworthiness is obtained in new designs, and try to prove that old designs are the only way to obtain a seaworthy boat you should try to understand how modern NA have obtained seaworthy boats with different design criteria than the one that was used 50 years ago.

There are several ways of obtaining a seaworthy boat and mass and a relatively high CG is one of them, unfortunately one that gives slow sailboats. There are other ways, like the ones (based on static and dynamic stability) that permits a beamy low mass boat with a very deep CG, like a class40 racer, to be not only fast but very seaworthy and that's a fact.

You should try to understand how that massif seaworthiness (that is a fact) is obtained in a boat that contradicts the ways it was obtained 50 years ago instead of, against the reality, assuming that boat cannot be seaworthy because it is not designed accordingly with the principles that 50 years ago were used to design seaworthy boats.

Regards

Paulo


----------



## barefootnavigator

Paulo you are right designers have long since abandoned full keel designs when it comes to production boats that require cheap quick building. They also abandoned the stay sail and bow sprite. I don't know how many of you have been paying attention but they both are back as high performance upgrades. It would appear the older designers got it right the first time. I have owned many fin and full keel boats, after 25 years of sailing I find I sleep better in a full keel than a fin keel so that's my preference. A good friend just lost his half million dollar fin keel to a submerged deadhead, his boat went down in under 3 minutes. If you want to know the difference in strength between full and fin keels, don't ask the designer, don't ask the builder, don.t ask the sailor. Ask the boat yard manager who has to do all the repairs on the boats, or at least the ones that didn't sink.


----------



## PCP

barefootnavigator said:


> Paulo you are right designers have long since abandoned full keel designs when it comes to production boats that require cheap quick building. ... It would appear the older designers got it right the first time. .. A good friend just lost his half million dollar fin keel to a submerged deadhead, his boat went down in under 3 minutes. If you want to know the difference in strength between full and fin keels, don't ask the designer, don't ask the builder, don.t ask the sailor. Ask the boat yard manager who has to do all the repairs on the boats, or at least the ones that didn't sink.


I agree with you that is possible to build a full keel boat stronger than a fin keel boat the same way that is not possible to build a full keel boat that is so efficient sailing as a fin keel boat (both boats being well designed).

The question here is if the strength we can achieve with a fin keel boat is sufficient to make a safe sailboat (and if so we can have better sailing boats) or if fin keel boats are dangerous.

The huge number of fin keel boats without problems and the very low percentage of problems show that modern materials and building techniques can provide safe fin keel boats.

Regarding being cheaper and quicker to build, as Jeff has pointed already here you got it wrong, it is more complicated and expensive to build a fin keel boat than a full keel boat. The structure that has to be built to transmit the efforts to the hull is very expensive to built.

Saying this I can understand that a very small minority prefers to have (new) a full keel boat instead of a fin keel boat the same way that I accept that a guy prefer to drive a big truck instead of a saloon because it is safer.

Regarding the used market I can easily understand that some full keel boats are so strong that can, after some tens of years, offer a better warranty of solidity than a fin keel boat with the same age, but each case is a case.

Regards

Paulo


----------



## BryceGTX

PCP said:


> I say that one is more stiff than the other? You have any doubt?
> 
> The stifness of a boat is directly related with the boat displacement and the sail area the boat can carry (SA/D). You can see that big difference yourself. Paulo


Yes, I definitely have a doubt that you know the racer is more stiff than the Benneteau Oceanis. Stiffness is a characteristic of the hull dimensions and weight distribution and has nothing to do with SA/D.

I am sure there are many readers scratching their heads at your post.

Specifically, stiffness is related to the moment of the area of the waterline and the volumetric displacement. It has nothing to do with sails.

You are inferring the stiffness from the SA/D. Problem I see is that the racer would tend to carry more dacron that the cruiser given the same stiffness. The way I see it, most good racers have a hull design that increases the stiffness dramatically with heel angle. This could even lead to a boat less stiff than the Oceanis at low heel angles.



PCP said:


> There are several ways of obtaining a seaworthy boat and mass and a relatively high CG is one of them, unfortunately one that gives slow sailboats.


My discussion is not about seaworthyness. That discussion has been hashed out in the multitude of threads about "Bluewater".

My discussion is specifically about rough water characteristics. And a higher CG by any stretch of the imagination most generally results in a poor rough water boat.

But ignoring that for a moment; again, you are assuming that everyone is willing to sacrifice everything for performance. Most cruisers are not.



PCP said:


> You should try to understand how that massif seaworthiness (that is a fact) is obtained in a boat that contradicts the ways it was obtained 50 years ago instead of, against the reality, assuming that boat cannot be seaworthy because it is not designed accordingly with the principles that 50 years ago were used to design seaworthy boats.


The principles of boat design have not changed in 50 years. Only the boat designs have changed in 50 years.

Again my discussion is not about seaworthy boats. And this thread is not about seaworthy boats.

My discussion is specifically about a charateristic of boats. That characteristic is pretty much what most cruisers are concerned with.

To put it into words that you might understand: Most people prefer that their masts stay pointed up and their keels stay pointed down.

To further this idea, people prefer that their masts stay pointed up even when the boat is going over waves.

Your two boats are boats that exhibit the above characteristic poorly. Rather, their relatively high hull siffness causes both boats to heel exactly with the waves. In this case I am relying on your clearly poor interpretation of stiffness.

Bryce


----------



## BryceGTX

PCP said:


> The question here is if the strength we can achieve with a fin keel boat is sufficient to make a safe sailboat (and if so we can have better sailing boats) or if fin keel boats are dangerous.
> 
> The huge number of fin keel boats without problems and the very low percentage of problems show that modern materials and building techniques can provide safe fin keel boats.
> 
> Paulo


I think you are missing barefootnavigator's point. Clearly, by any measure a 9 foot fin keel that is thinner and shorter will be much more subject to damage from a hit than a 2 foot keel that is both wider and longer. This is a characteristic of the dimensions that cannot be argued.

Presumably both boats have the same construction materials and techniques because they are built in the same years. Lets ignore racing boats for a moment as these guys have bottomless pocket books.

So in this discussion, you are relating how great this racer 40 is because it has a very long keel. Which as we know can create some quite large forces. And you say this is very good. However, earlier in this thread you are concerned about a boat tripping over its keel. This very long keel on this racer presents exactly the same scenario as your earlier discussion of the boat tripping over the keel given the same sea conditions. And I had just got finished talking about the same thing only a few posts back with Jeff discussing why this happens.

So which is it Paulo.. do we use a very deep keel to cause our boat to trip over its keel and more likely to break in a hit, or do we use a longer/wider keel (not deeper) that has neither problem.
Bryce


----------



## PCP

BryceGTX said:


> Yes, I definitely have a doubt that you know the racer is more stiff than the Benneteau Oceanis. Stiffness is a characteristic of the hull dimensions and weight distribution and has nothing to do with SA/D.
> 
> I am sure there are many readers scratching their heads at your post.
> 
> ....
> 
> Bryce


Jesus, I give up on you Bryce

You fail to acknowledge even the most obvious facts

So you have doubts that a 40 class racer is more stiff than a 40ft Oceanis?

The 40 class racer has much more hull form stability, being much beamier with a much flatter hull and the 40class boat has also a much bigger B/D not to mention that it has all ballast in a torpedo at the end of a 3 m draft while the Oceanis has only a 2 m draft and a keel with the weight more distributed.

How the hell do you think stiffness it is obtained in a sailboat?

I am out!

Hey guys, you can keep scratching your heads

Regards

Paulo


----------



## GBurton

PCP said:


> Jesus, I give up on you Bryce
> 
> You fail to acknowledge even the most obvious facts
> 
> So you have doubts that a 40 class racer is more stiff than a 40ft Oceanis?
> 
> The 40 class racer has much more hull form stability, being much beamier with a much flatter hull and the 40class boat has also a much bigger B/D not to mention that it has all ballast in a torpedo at the end of a 3 m draft while the Oceanis has only a 2 m draft and a keel with the weight more distributed.
> 
> How the hell do you think stiffness it is obtained in a sailboat?
> 
> I am out!
> 
> Hey guys, you can keep scratching your heads
> 
> Regards
> 
> Paulo


On the contrary Paulo, Bryce makes a lot of sense whilst you resort to personal attack.


----------



## PCP

GBurton said:


> On the contrary Paulo, Bryce makes a lot of sense whilst you resort to personal attack.





GBurton said:


> On the contrary Paulo, Bryce makes a lot of sense whilst you resort to personal attack.


Can you explain where is the personal attack?

Regarding sense do you mean do you also believe that an Oceanis 40 is more stiff (or as any comparison in what regards stiffness) than a 40class racer?

Or maybe you don't know the boats?

*Take a look at the huge amount of sail this boats can carry even with lots of wind and bad weather and see how they remain steady and resist heeling.
*

The 40 class boats are these boats:






That means the Oceanis 40 is (obviously) much less stiff than a 40class racer, resisting a lot less to the wind force that it is applied in its sails. With the same sail area the 40class carries, the Oceanis 40 would not be able to resist heeling and would capsize.

and since *"stiffness (is) the ability of the boat to resist the heeling force of the sails"* how can someone say than an Oceanis is less Stiff than a 40class racer?

It is obvious that the 40class boat can carry much more sail area and even so heel less than the Oceanis. This is not obvious to you?

That quote about stiffness is from a well known NA. I cannot copy the article but you can read it here. It is very interesting article:

Performance Cruising

More definitions about stiffness in a sailboat:

*stiff - A boat that resists heeling.*

Boat Mall, the online boat shop, sell or find your dreamboat, classified boat ads

Regards

Paulo


----------



## Familycruisers

Bilge keels are better than both, so there --


----------



## GBurton

Paulo, this open 60 does not appear to be very stiff. Perhaps it has something to do with the way it is being sailed?


----------



## PCP

GBurton said:


> Paulo, this open 60 does not appear to be very stiff. Perhaps it has something to do with the way it is being sailed?


I assume(and hope) you are kidding

The stiffness of a boat has not to do with the way the boat is sailed and an Open 60 is one of the stiffest boats you can have. Only because it is so stiff it can be sailed that way and remain steady on that position allowing that Alex to be on the keel of Hugo Boss with a Hugo Boss suit. cool











Regards

Paulo


----------



## GBurton

Whooooooosh....


----------



## BryceGTX

PCP said:


> Jesus, I give up on you Bryce
> 
> You fail to acknowledge even the most obvious facts
> 
> So you have doubts that a 40 class racer is more stiff than a 40ft Oceanis?
> 
> The 40 class racer has much more hull form stability, being much beamier with a much flatter hull and the 40class boat has also a much bigger B/D not to mention that it has all ballast in a torpedo at the end of a 3 m draft while the Oceanis has only a 2 m draft and a keel with the weight more distributed.
> 
> How the hell do you think stiffness it is obtained in a sailboat?
> 
> Paulo


Stffness is invariably created by hull design.. plain and simple. You can roll your eyes all you want, but it does not change that fact. However, for this discussion, not sure why we care.

Here are the facts. Modern wide bodied racers get their righting moment from wide hulls. They are lightened as much as possible to reduce hull resistance. This provide the best acceleration. Because they are lightened so much, their center of gravity is often higher than a good rough water boat.

The most obvious example of a high CG boat having a large righting moment is a catamaran. Clearly the righting moment is created by hull design, not mass. Wide racers use the exact same idea, only with a single hull.

For a modern racer, the keel mass only needs to be as heavy as required to provide a certain amount of moment to balance the standing rigging and to allow the boat to have a RM diagram that extends to a large heeling angle. The total weight is often defined by rules. So the goal is to reduce the hull weight to an absolute minimum and instead place any left over weight on the keel.

Your suggestion that the Class 40 boat is a good rough water boat undoubtably comes from racers whose goal is to go fast in spite of the weather.

Lets put a 65 year old couple on that POS racer and let them get unexpectedly caught in mid Atlantic like the big blow last year November?? north of Bermuda for 3 days. Since there is only two of them, they will not be able to sail through, so they will be forced to resort to stabilizing tactics. I bet they will have a radically different viewpoint than you on what a rough water boat is. Not everything is about performance.

As far as I am concerned neither of these boats are rough water boats. Picking one over the other is like asking which one will be less miserable in rough water.
Bryce


----------



## BryceGTX

PCP said:


> Just have a look at two boats, *with similar types of hulls*, about the same size, one with 4.5T and a substantial part of its weight down on a bulb at the end of a 3m draft, the other one with 9T with much more proportion of weight in its hull and 1.55m of draft. Both are well designed boats the*total RM would not be very different* (due to the much bigger mass of the heavier boat) and the lighter boat will be massively stiffer.
> 
> We are talking here about a 40 class racer and about an Oceanis 41.
> Paulo


Just for kicks, I decided to check your original premise. Contrary to what you say, these boats have radically different hulls. Not sure why you even posted this.

And contrary to what you say, they have radically different RM diagrams. The racers RM would be considerably higher by a wide margin. Not sure why you posted this.

Is the Racer 40 stiffer. Probably, but then again nothing you said originally was true.

The racer has 50% more hull moment only due to its increased width. I would have to look closer at the mass moment. This boat has an RM quite higher than the Oceanis. Again.. where did you come up with the idea these boats had similar RMs?
Bryce


----------



## PCP

BryceGTX said:


> ..
> And contrary to what you say, they have radically different RM diagrams. The racers RM would be considerably higher by a wide margin. ..
> 
> ......This boat has an RM double what the Oceanis has. Again.. where did you come up with the idea these boats had similar RMs?
> Bryce


Glad to see that you finally agree that the 40class boat is a lot stiffer.

Since it seems that we are agreeing, I have to answer to a honest question

Regarding RM the ones from the two boats would not be that different.

What would be *massively different is the GZ curve*, the arm length curve. For the RM curve *you have to multiply those values by the displacement of the boat and as the Oceanis weights about the double* that will make things more even. In the end it would not be a considerable difference.

Regards

Paulo


----------



## BryceGTX

PCP said:


> Glad to see that you finally agree that the 40class boat is a lot stiffer.
> 
> Since it seems that we are agreeing, I have to answer to a honest question
> 
> Regarding RM the ones from the two boats would not be that different.
> 
> What would be *massively different is the GS curve*, the arm length curve. For the RM curve *you have to multiply those values by the displacement of the boat and as the Oceanis weights about the double* that will make things more even. In the end it would not be a considerable difference.
> 
> Regards
> 
> Paulo


LOL.. you best quit while you are no so far behind.

I did not say definitively it was stiffer, could be. You seem to be confusing RM with stiffness which I can imagine would be a common mistake. They are quite different things. If you want to convince anyone of anything, just post the RM diagrams.

But ignoring that for a moment, you are comparing two boats that are miserable in rough water. So not sure that you are making a rational point.

You are just asking which boat will be more or less miserable. Now if I had to be on one of these boats in rough water with my wife, no doubt I would pick the Oceanis. And it is possibly less stiff which supports what I said earlier. However, I would pick it because it invariably would be more comfortable on a drouge and obviously, it is a better cruising boat.
Bryce


----------



## PCP

BryceGTX said:


> LOL.. you best quit while you are no so far behind.
> 
> I did not say definitively it was stiffer, could be. ...
> Bryce





BryceGTX said:


> ...
> 
> Is the Racer 40 stiffer. *Probably*,
> ...
> Bryce


Probably means that there is a big chance to be or it is a way not to say exactly that it is



BryceGTX said:


> Stffness is* invariably* created by hull design.. plain and simple. ...
> Bryce


So if on the same boat I would increase significantly the ballast, or put the same ballast a lot deeper (bigger draft) I would not get a more stiffer boat? and as "stiffness (is) the ability of the boat to resist the heeling force of the sails" it would not be a boat that heel less carrying the same amount of sail?

No matter how confusing your language you seem to fail to understand the most basic principles in what regards stability in what regards sailing and stiffness.

There are two ways of increasing stiffness in a sail boat: increasing beam and lowering the CG (increasing ballast or bigger draft). Increasing beam only increases stability at relatively low angles of heel, increasing CG has a lesser effect at low angles and increased effect with heel.

Best regards

Paulo


----------



## BryceGTX

PCP said:


> *40class racer is massively more stiff **and by your reasoning, since both boats share the same kind of hull, the Class40 should be less of a rough water boat.
> *


*



PCP said:



Probably means that there is a big chance to be or it is a way not to say exactly that it is

Click to expand...

I asked a number of times that you post the stability diagrams for the two boats so you might immediately see otherwise. I wanted to see specifically the boats you were comparing. Obviously, one boat is a very specific boat (Oceanis). The racer represents a whole class of boats with varying RM diagrams.

However, I wil post the representative RM diagrams to see if what you say makes sense.

The red plot is the RM diagram for the oceanis. The blue diagram is the RM of the racer. As we see, the racer has a much larger RM value that the Oceanis sooner in the RM diagram. And as you say, the RM has similar amplitude.

Now as we all know, stiffness is the derivative of the RM diagram. So at the top, I show Where each boat has the higer derivative. The Oceanis clearly has a higher stiffness over more of the RM diagram that the racer.

Usually a cruiser is more stiff near zero. The racer is more stiff at some heeling angle above a few degrees up to probably about 30 to 40 degrees. Afterwards, the oceanis is more stiff. Clearly these break points are different depending on who designed the racer.

Such RM differences are typical for racers and crusier. But again I ask, why would anyone think a racer is a rough water boat??

So remind me again.. which boat is more stiff? Better yet.. Massively more stiff???
Bryce*


----------



## BryceGTX

PCP said:


> No matter how confusing your language you seem to fail to understand the most basic principles in what regards stability in what regards sailing and stiffness.


It is clear by the previous post, the Oceanis is more stiff could be even *Massively more stiff*  than the racer over more of the RM diagram. But you say I am confusing stiffness????



PCP said:


> There are two ways of increasing stiffness in a sail boat: increasing beam and lowering the CG (increasing ballast or bigger draft). Increasing beam only increases stability at relatively low angles of heel, increasing CG has a lesser effect at low angles and increased effect with heel.


LOL.. you are mixing stiffness and RM. Careful.. you may get in trouble again.
Bryce


----------



## oldragbaggers

PorFin said:


> +1. We've got a full keel with a barn door rudder, and I'm here to tell you backing is ALWAYS an adventure. If there is absolutely no wind and no current, I can _usually_ know how the beast will track in reverse. Mostly it's all about using the throttle intermittently to balance prop walk with having the rudder pretty hard to starboard (the rudder imparts very little turning effort when in reverse.)
> 
> However, when conditions are not totally benign the old gal loves to make my life interesting. Doing the mental gymnastics thinking about the opposing forces keeps me on my toes, but usually I'm left with just getting her out into a fairway with enough maneuvering space to spin her until I get pointed in the right direction.
> 
> If there's a considerable cross wind or current, I've got to weigh the possibility of becoming a "bumper boat" against my desire/need to get underway.


You just described backing our Cape Dory 28 to a tee.


----------



## pvajko

*German Yacht Magazine Article on Full vs. Fin Keel*

The 25/26 issue of the German bi-weekly Yacht magazine has a very interesting article comparing a full keel (Vindö 40, 31ft, 1971), a moderate fin keel with skeg (Hallberg Rassy 29, 1981) and a modern fin keel boat (Sun Odyssey 30i, 2008).

They sailed the three boats together in 5 Bft wind and 3 to 5 feet waves to find out which is the most comfortable to sail under these conditions.

They had 3 crews rotating between the boats and all crews reported that the HR and the Vindö are not only more comfortable but the HR even sailed higher and faster than the Sun Odyssey.

(I'm a little disappointed, I expected a German magazine to use 3D accelerometers and data loggers and software to evaluate the boat movements and not just rely on crew opinion )

Let me cite the closing sentences of the article:
_*
"The most common argument used to justify the uncomfortable motion of modern cruising boats is that the typical customer (young families, older couples and charter crews) won't leave the marina in winds over 4 Beaufort anyway. For that, these boats are significantly faster in light winds than they predecessors.

The latter may be true. The first, however, should probably be reversed: maybe the reason people don't sail them in rough water is that these boats are too uncomfortable for that?"*_

_"Häufigstes Argument zur Rechtfertigung des unbequemen Seegangsverhaltens moderner Fahrtenyachten ist, dass sie von der angepeilten Klientel - jungen Familien, älteren Paaren und Chartercrews - bei Bedingungen jenseits der 4 Beaufort ohnehin nicht mehr bewegt würden. Da blieben die meisten lieber im Hafen. Dafür seien sie im unteren Windbereich deutlich schneller als ihre Vorgäger.

Letztgennantes Argument mag stimmen. Auf das andere kann jedoch auch der Umkehrschluss angewandt werden: Wird vielleicht nicht mehr bei Seegang hinausgefahren, weil die Yachten dafür zu unkomfortabel sind?"
_


----------



## bjung

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



pvajko said:


> The 25/26 issue of the German bi-weekly Yacht magazine has a very interesting article comparing a full keel (Vindö 40, 31ft, 1971), a moderate fin keel with skeg (Hallberg Rassy 29, 1981) and a modern fin keel boat (Sun Odyssey 30i, 2008).
> 
> They sailed the three boats together in 5 Bft wind and 3 to 5 feet waves to find out which is the most comfortable to sail under these conditions.
> 
> They had 3 crews rotating between the boats and all crews reported that the HR and the Vindö are not only more comfortable but the HR even sailed higher and faster than the Sun Odyssey.
> 
> (I'm a little disappointed, I expected a German magazine to use 3D accelerometers and data loggers and software to evaluate the boat movements and not just rely on crew opinion )
> 
> Let me cite the closing sentences of the article:
> _*
> "The most common argument used to justify the uncomfortable motion of modern cruising boats is that the typical customer (young families, older couples and charter crews) won't leave the marina in winds over 4 Beaufort anyway. For that, these boats are significantly faster in light winds than they predecessors.
> 
> The latter may be true. The first, however, should probably be reversed: maybe the reason people don't sail them in rough water is that these boats are too uncomfortable for that?"*_
> 
> _"Häufigstes Argument zur Rechtfertigung des unbequemen Seegangsverhaltens moderner Fahrtenyachten ist, dass sie von der angepeilten Klientel - jungen Familien, älteren Paaren und Chartercrews - bei Bedingungen jenseits der 4 Beaufort ohnehin nicht mehr bewegt würden. Da blieben die meisten lieber im Hafen. Dafür seien sie im unteren Windbereich deutlich schneller als ihre Vorgäger.
> 
> Letztgennantes Argument mag stimmen. Auf das andere kann jedoch auch der Umkehrschluss angewandt werden: Wird vielleicht nicht mehr bei Seegang hinausgefahren, weil die Yachten dafür zu unkomfortabel sind?"
> _


Here is the Video.In der Welle: Langkieler gegen Kurzkieler - Yacht TV - Segel Videos von Europas größtem Yacht Magazin
It is definetly an interresting article, but I am not sure we can make the deductions they made purely on keel shape, because these boats are very differrent in other regards, beam, hullshape, displacement, ballast ratio, etc.. However, one propably can safely assume that the SO 30i and a lot of current production boats are built for space below, rather than sailing.


----------



## PCP

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



pvajko said:


> The 25/26 issue of the German bi-weekly Yacht magazine has a very interesting article comparing a full keel (Vindö 40, 31ft, 1971), a moderate fin keel with skeg (Hallberg Rassy 29, 1981) and a modern fin keel boat (Sun Odyssey 30i, 2008).
> 
> They sailed the three boats together in 5 Bft wind and 3 to 5 feet waves to find out which is the most comfortable to sail under these conditions.
> 
> They had 3 crews rotating between the boats and all crews reported that the HR and the Vindö are not only more comfortable but the HR even sailed higher and faster than the Sun Odyssey.
> 
> (I'm a little disappointed, I expected a German magazine to use 3D accelerometers and data loggers and software to evaluate the boat movements and not just rely on crew opinion )
> 
> Let me cite the closing sentences of the article:
> _*
> "The most common argument used to justify the uncomfortable motion of modern cruising boats is that the typical customer (young families, older couples and charter crews) won't leave the marina in winds over 4 Beaufort anyway. For that, these boats are significantly faster in light winds than they predecessors.
> 
> The latter may be true. The first, however, should probably be reversed: maybe the reason people don't sail them in rough water is that these boats are too uncomfortable for that?"*_
> 
> _"Häufigstes Argument zur Rechtfertigung des unbequemen Seegangsverhaltens moderner Fahrtenyachten ist, dass sie von der angepeilten Klientel - jungen Familien, älteren Paaren und Chartercrews - bei Bedingungen jenseits der 4 Beaufort ohnehin nicht mehr bewegt würden. Da blieben die meisten lieber im Hafen. Dafür seien sie im unteren Windbereich deutlich schneller als ihre Vorgäger.
> 
> Letztgennantes Argument mag stimmen. Auf das andere kann jedoch auch der Umkehrschluss angewandt werden: Wird vielleicht nicht mehr bei Seegang hinausgefahren, weil die Yachten dafür zu unkomfortabel sind?"
> _


I have posted about that on the interesting sailboat thread.

The comparison was made on the conditions a heavy boat with a lot of rocker would be at his best and a modern boat at is worst. They also chose for the comparison a particularly tender boat. If they had chosen the slightly bigger jeanneau 33i (much more stiff) I am sure the results would be different, not regarding comfort but speed.

That different performance with lots if wind and short waves upwind is the weak point of many modern mass production cruisers like Hunter, Catalina, Oceanis or Dufour (just to mention some). To go really fast on those conditions you need a much stiffer performance cruiser like for instance a Xp or First. It would no be more comfortable, or at least it will have a completely different motion: A more ample one (pitch) on the heavier boat, a less ample but faster and less soft on the faster boat. The less comfortable motion has also to do with speed. More speed, less comfort.

Anyway that has nothing to do with the type of keel but with the type of boat: If you keep the hulls of the heavier boats and substitute the keels by modern ones, keeping the weight but increasing RM, you would have a similar motion but a faster boat and one able to go faster upwind. Off course, faster would mean also more uncomfortable (at more speed) but that is another story.

Regardimg this:

*"The most common argument used to justify the uncomfortable motion of modern cruising boats is that the typical customer (young families, older couples and charter crews) won't leave the marina in winds over 4 Beaufort anyway. For that, these boats are significantly faster in light winds than they predecessors."*

I guess that they forgot to mention two things, the first one is that they should have added to that sentence: *"won't leave the marina in winds over 4 Beaufort* *to sail upwind* *anyway"*

and like that, that's a fact.

The second one is that they should have mentioned also that the price of a boat has more to do with weight than with length (I mean normal boats made with the same materials), so boats like the HR or Vindo, even if with modern and more efficient keels, would be massively more expensive than a boat with the same lenght like the Jeanneau, as they are all the small heavy boats on the market. With that money a sailor could buy a much bigger boat that would be faster and more comfortable. Yes. That is really why the boats on the market are what they are. Neither the designers or the sailors are dumb

Regards

Paulo


----------



## pvajko

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



bjung said:


> I am not sure we can make the deductions they made purely on keel shape, because these boats are very different in other regards, beam, hullshape, displacement, ballast ratio, etc..


The title is full vs. fin keel and may be misleading, but the article has lots of information and detailed explanation on the hull shape as well.


----------



## pvajko

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



PCP said:


> a heavy boat with a lot of rocker would be at his best and a modern boat at is worst.


Don't know what do you mean by heavy, the Vindö is 5 tons, that's true, but the HR 29 is 4, the Sun Odyssey 3.9. That 100kg makes all the difference?


----------



## Brent Swain

Love my twin keels and I wouldn't want anything else, nor would most of my recent clients.


----------



## PCP

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



pvajko said:


> Don't know what do you mean by heavy, the Vindö is 5 tons, that's true, but the HR 29 is 4, the Sun Odyssey 3.9. That 100kg makes all the difference?


No, I guess not but then the HR 29 is a fin keel boat not a full keel boat.

In what regards the HR 29 the hull is just more adapted to sail upwind with waves and that has to do not only with a lot more rocker, a more narrow hull but mainly with a much bigger D/B ratio. The HR29 is a well designed boat, a stiff one. I don't like the SO 30 that is a boat with an unusual low B/D. That makes it tender upwind with waves and that's the main reason for its bad performance.

If you had against those boats, on those conditions, a modern stiff boat, the boat would be less comfortable but would be faster.

Have a good Christmas

Regards

Paulo


----------



## wolfenzee

Once the wind speed gets to the point where comfort would be an issue my boat is doing hull speed (9kts I am doing hull speed,6.5kt, under main and working jib). So unless you are talking about racing fin keels that can plane, a fin keel would not be any faster. 30' at 8ton it is smooth in nasty seas


----------



## PCP

wolfenzee said:


> .So unless you are talking about racing fin keels that can plane, a fin keel would not be any faster. 30' at 8ton it is smooth in nasty seas


there are no racing fin keels. Fact is that most modern performance cruisers and even some mainstream cruising mass production boats use similar keels to the ones that are used in racers just with a smaller draft.

Regards

Paulo


----------



## BryceGTX

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



PCP said:


> The comparison was made on the conditions a heavy boat with a lot of rocker would be at his best and a modern boat at is worst. They also chose for the comparison a particularly tender boat. If they had chosen the slightly bigger jeanneau 33i (much more stiff) I am sure the results would be different


Whoa.. a 30i is a particularly tender boat??? Clearly it is representative of a stiff production boat of the 30 foot size compared to the others. The test clearly shows the more comfortable boats are heavier boats with more mass righting moment.



PCP said:


> That different performance with lots if wind and short waves upwind is the weak point of many modern mass production cruisers like Hunter, Catalina, Oceanis or Dufour (just to mention some). To go really fast on those conditions you need a much stiffer performance cruiser like for instance a Xp or First. It would no be more comfortable, or at least it will have a completely different motion:.
> Paulo


No, clearly comfort is related to mass and associated hull/keel design.. I am continually amazed that this simple fact seems to escape you.

I also don't see Hunter and Catalina which traditionally have heavier boats equivalent to the Oceanis which tends to be lighter.

Sorry.. you are wrong.
Bryce


----------



## PCP

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



BryceGTX said:


> Whoa.. a 30i is a particularly tender boat??? Clearly it is representative of a stiff production boat of the 30 foot size compared to the others.
> .....
> Sorry.. you are wrong.
> Bryce


Sure, you are right as usual

The *Jeanneau 30* has a B/D ratio of only *24%*, the Jeanneau 33i has *32%*, the Benetau First 30 has *29%*, Dehler 29, *37%*, Dufour 335 has *28%*, Hanse 325 has *29%*, A31 has *40%*, the Elan 310 has *28%*, Delphia 31 has *33%*, Benteau Oceanis *25%*, Bavaria 33 *26%*.

Most of these boats have or more draft or more modern and efficient keels that will make the difference in RM even more meaningful. To my knowledge there are no other 29/33ft as tender in the market as the Jeanneau 30.

Regards

Paulo


----------



## wolfenzee

My 30' full keel has a B/D ratio of about 25% (3800lb ballast/15,000 disp)


----------



## blt2ski

My previous generation by 3 or 4 Jeanneau, has 2400 to 6500 lbs of boat. With a 5.5' draft.

At the end of the day, if the boat works for your purpose, keel design and where the ballast is set at works, away you go! enjoy your boat! I'll still take my Jeanneau over an equal Catalina with a lead keel, I may heel a bit more, but I am faster in all but light winds!

Marty


----------



## blt2ski

Wolf,

Curious, is your B/D only using the "lead" in you keel? if so, you probably have a higher % than that, as one "should" IMHO include the rest of the keel as ballast per say. A swag would then be 4500lbs/15K = 30%. As you really have what is a precursor to todays T keels, but do to materials and knowledge of some material strength, many things were designs heavier than need be. With what is probably a 5'long, 6"wide, 1'high chunk of lead at the bottom of your keel, it behaves like a heavier fin keel from a stability point of view.

my 01 on the subject.

Marty


----------



## PCP

wolfenzee said:


> My 30' full keel has a B/D ratio of about 25% (3800lb ballast/15,000 disp)


That is pretty low for a full keel and points to a tender boat. If you search and look at several full keelers you would see that the average is over 30%. They need more ballast because for the same dimension full keels had normally less draft.

what is the draft of your boat?

Regards

Paulo


----------



## wolfenzee

blt2ski said:


> My previous generation by 3 or 4 Jeanneau, has 2400 to 6500 lbs of boat. With a 5.5' draft.
> 
> At the end of the day, if the boat works for your purpose, keel design and where the ballast is set at works, away you go! enjoy your boat! I'll still take my Jeanneau over an equal Catalina with a lead keel, I may heel a bit more, but I am faster in all but light winds!
> 
> Marty


A light weight disp fin keel will do better than my boat in light air (<5kt), but not by much, alot of heavy disp full keels can't get out of their own way in light air, my boat has always surprised me in light air. It doesn't take much for me to get to hull speed, 10kt wind w/main and working jib = 6.5kt. My boat starts to excel over the lighter fin keels as the wind kicks up, and when things get dicey I would have anything else. My "obsolete/antiquated" rig works differently and behaves differently with performance weeks over the years is quite satisfying, aside from performance, she has a style and grace that just doesn't happen in production boats. I respect "to each his own" as should everyone.


----------



## Brent Swain

Bear in mind the buoyancy of a wide, full length keel.


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## wolfenzee

PCP said:


> That is pretty low for a full keel and points to a tender boat. If you search and look at several full keelers you would see that the average is over 30%. They need more ballast because for the same dimension full keels had normally less draft.
> 
> what is the draft of your boat?
> 
> Regards
> 
> Paulo


My draft is 5' original ballast was 3200lb then 800 more was added totaling 4000, disp is about 15,000 (27%) still a little tender. Original design called for 13,200 w/3200 ballast (24%), but construction method ended up with a much heavier boat (still riding on design water line). It doesn't take much to get the boat over to 30degree heel, but once there it doesn't want to go any further (builder named the boat "Roll N' Go"), I know, I've tried, it's better to discover your boats limits before they get shown to you.


----------



## Rockter

Get one of these (or similar)....






You can't beat a long keel in these conditions.
.


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## BryceGTX

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



PCP said:


> Sure, you are right as usual


Makes sense as I only post when you are wrong.



PCP said:


> The *Jeanneau 30* has a B/D ratio of only *24%*, the Jeanneau 33i has *32%*
> 
> Most of these boats have or more draft or more modern and efficient keels that will make the difference in RM even more meaningful. To my knowledge there are no other 29/33ft as tender in the market as the Jeanneau 30.
> 
> Regards
> 
> Paulo


B/D can only be used as a measure of stiffness when the hulls are identical and the weight is proportional the same. Clearly not the case here.

And what do we care about the other boats you listed? They have nothing to do with the discussion at hand.

And clearly RM only is a measure of stiffness when the RM diagrams are identical shape. Clearly not the case here.

I can't imagine why you bring up the 33, when this test compares 30 foot and under boats.

So basically, your discussion of B/D has no meaning here. I suggest you learn a bit about what stiffness means.
Bryce


----------



## PCP

*Re: German Yacht Magazine Article on Full vs. Fin Keel*

This was what was in question, this statement of yours:



BryceGTX said:


> Whoa.. *a 30i is a particularly tender boat??? Clearly it is representative of a stiff production boat of the 30 foot size compared to the others.
> Sorry.. you are wrong.*
> Bryce





PCP said:


> Sure, you are right as usual
> The *Jeanneau 30* has a B/D ratio of only *24%*, the Jeanneau 33i has *32%*, the Benetau First 30 has *29%*, Dehler 29, *37%*, Dufour 335 has *28%*, Hanse 325 has *29%*, A31 has *40%*, the Elan 310 has *28%*, Delphia 31 has *33%*, Benteau Oceanis *25%*, Bavaria 33 *26%*.
> 
> Most of these boats have or more draft or more modern and efficient keels that will make the difference in RM even more meaningful. To my knowledge there are no other 29/33ft as tender in the market as the Jeanneau 30.


and you say now about that:



BryceGTX said:


> Makes sense as I only post when you are wrong.
> 
> *B/D can only be used as a measure of stiffness when the hulls are identical and the weight is proportional the same. Clearly not the case here.*
> 
> ... I suggest you learn a bit about what stiffness means.
> Bryce


*Here you have the hull of the 30i:*










*Here you have the hull of the 33i*:










The Displ/lenght ratio is: 162.7 to 169.6

The very small difference in displacement/length has to do more with the much bigger B/D of the 33i then with any difference in the hull type or keel type. Both boats are even designed by the same NA.

Clearly it is the same kind of hull, the same kind of keel, the same kind of Displ/Lenght ratio.

*How difficult is the check the data before posting?*

Regards

Paulo


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## wolfenzee

Hull construction does have alot to do with it. My hull is 1" thick mahagony strip plank, glued and top nailed with 3" nails, screwed onto 2x3" double frames (which are bolted together with 3/8" through bolts) and 1/4" ceiling....to finish it off the builder also covered the boat with two layers of fiberglass. The weight is distributed alot more evenly. 
B/D ratio by itself doesn't mean alot whole lot, it is simply "An indication of a boats stiffness or it's ability to resist heeling", some boats actually perform better when heeled (mine does best at 25-30 degrees and it doesn't take much to get it there) and some of weekend cruisers get nervous if there boat goes beyond 10 degrees so there are boats designed accordingly. 
The height of the mast, sail area and beam all are necessary calculations here is a performance calculator for cruising boats: SloopIT - Boat performance calculator


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## BryceGTX

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



PCP said:


> This was what was in question, this statement of yours:
> 
> *Here you have the hull of the 30i:*
> 
> *Here you have the hull of the 33i*:
> 
> The Displ/lenght ratio is: 162.7 to 169.6
> 
> The very small difference in displacement/length has to do more with the much bigger B/D of the 33i then with any difference in the hull type or keel type. Both boats are even designed by the same NA.
> 
> Clearly it is the same kind of hull, the same kind of keel, the same kind of Displ/Lenght ratio.
> 
> *How difficult is the check the data before posting?*
> 
> Regards
> 
> Paulo


So I should check a 33 is bigger than a 30???? Who cares?



PCP said:


> They also chose for the comparison a particularly tender boat. If they had chosen the slightly bigger jeanneau 33i (much more stiff) I am sure the results would be different, not regarding comfort but speed.





> The 25/26 issue of the German bi-weekly Yacht magazine has a very interesting article comparing a full keel (Vindö 40, 31ft, 1971), a moderate fin keel with skeg (Hallberg Rassy 29, 1981) and a modern fin keel boat (Sun Odyssey 30i, 2008).


Paulo.. given that the three boats in question were 31ft, 29 ft and 30 foot.. why in the world would you suggest than anyone would compare these boats to a 33?

Who cares that a 33 is more stiff or faster or whatever.. clearly it is in a different class...
Bryce


----------



## PCP

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



BryceGTX said:


> So I should check a 33 is bigger than a 30???? Who cares?
> 
> Paulo.. given that the three boats in question were 31ft, 29 ft and 30 foot.. why in the world would you suggest than anyone would compare these boats to a 33?
> 
> Who cares that a 33 is more stiff or faster or whatever.. clearly it is in a different class...
> Bryce


Sometimes is difficult to communicate with you. I have said that the modern 30ft they had used for comparison (a Jeanneau 30) was particularly tender, I give as example the 33ft from jeanneau as a boat much more stiff, even from the same line and brand

You said that the Jeanneau 30 was a good example in what regards the average stiffness of modern 30fts and I showed that you were wrong, that in fact I cannot find one as tender and posted the B/D of almost all 30ft on the market.

If that comparison was made with a Dehler 29 or a A31 the results would be very different, not in what regards sea motion but in what regards upwind speed. The main reason of the poor performance of the Jeanneau 30i upwind has nothing to do with being a fin keel or a full keel but with the boat being tender, exceptionally tender.

The better performer upwind on that test was not from the full keel (Vindo 40) but the one of other fin keel, the smaller boat, the Halberg-Rassy 29.

Regards

Paulo


----------



## outbound

I've owned full keeled boats with encapsulated ballast, one off fin keeled with keel bolts, modified fin with bolts . It's been mentioned several times in this thread full keel boats have encapsulated ballast (not always true) which runs the risk of complete ruin in a hard grounding and bolt on keels do not. Given I just spent my kids inheritance on a high aspect bulbed fin keel boat with encapsulated ballast (yes they exist) is there any data to support these statements.?Is this just ancedotal. Would think just like a properly engineered spade rudder can be stronger than a skeg hung one -a properly engineered fin with encapsulated ballast should be as strong or stronger than keel bolted.To the point that the grounding would have to produce whole structure failure of the vessel regardless of encapsulated or bolted. ?Are Shannons and Outbounds lousy boats.
P.S.- right on Paulo -having lived with both beasts unless thin water precludes it's a fin that's a better choice- just like we don't see many gaff rigged schooners being made these days unless we are in Lundenburg and see more solents modern fin keel boats can tract better, sail better and are as safe or safer in bad weather if properly designed and constructed. One post was kind enough to have a link that allowed comparisions. 
please keep this thread going
Tx,


----------



## L124C

Faster said:


> If a full keel was really the absolute optimum for offshore sailing we'd still see the Suhali's on the Volvo Ocean Race. (and I imagine a few of those crew, crawling soaking wet into an equally wet berth might well wish they'd chosen that ride from time to time)


While most of your post was thoughtful and well said (as usual), I have to call you on this analogy. Few things are "absolute" in this world, and I don't think anyone has claimed that the advantage of a full keel is speed. Don't know what "Suhali's are, but I assume they had an ample keel. On any race boat (offshore or otherwise), I think the priority is going to be speed. Not - sea kindness (as you point out), tracking, safety, shallow draft and certainly not durability after running aground. I don't think the OP was asking about offshore racing.


----------



## jameswilson29

"Suhali" was the name of Robin Knox Johnson's boat that won the first solo nonstop round the world race.

It was a heavy, old-fashioned, full-keeled, Colin Archer design that survived the race where all others were eliminated due to material failures or insanity in the case of Donald Crowhurst. It averaged 4 knots per hour - the classic 4ksb.


----------



## Faster

L124C said:


> While most of your post was thoughtful and well said (as usual), I have to call you on this analogy. Few things are "absolute" in this world, and I don't think anyone has claimed that the advantage of a full keel is speed. Don't know what "Suhali's are, but I assume they had an ample keel. On any race boat (offshore or otherwise), I think the priority is going to be speed. Not - sea kindness (as you point out), tracking, safety, shallow draft and certainly not durability after running aground. I don't think the OP was asking about offshore racing.


Thanks.... and yes, that statement may well have been an exaggeration (although there are a few W32 posters here that might not think so...


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## PCP

L124C said:


> ... I don't think anyone has claimed that the advantage of a full keel is speed. Don't know what "Suhali's are, but I assume they had an ample keel. On any race boat (offshore or otherwise), I think the priority is going to be speed. Not - sea kindness (as you point out), tracking, safety, shallow draft and certainly not durability after running aground. I don't think the OP was asking about offshore racing.


Sea-kindness has not to do with the type of keel but with the hull design and boat weight (inertia). In what regards tracking a well design fin keel can be as good as a full keel and certainly they point better and provide less drag.

Regarding draft, for the ones that need it modern keels offer swing ballasted keels that are very similar in performance with fin keels and offer a smaller draft than full keels.

You call it performance I call it a better sailing boat (a boat that sails better) and that is not important only to racers but to all cruisers.

Regarding durability I don't see why a boat with a fin keel would be less durable than a boat with a full keel.

Regarding being more resistant to grounding I guess you are right even if each case is a case. Anyway take a look at this videos. Do you really think that you need more resistance than this? Take into consideration that is a very light performance production cruiser with a big draft (2.30m). Normally mainstream production cruisers are more heavily built and have less draft.











Skerries boat "Raging Bull" crashes into the rocks during a storm from Silverscreen Media on Vimeo.

Regards

Paulo


----------



## BryceGTX

*Re: German Yacht Magazine Article on Full vs. Fin Keel*



PCP said:


> I have said that the modern 30ft they had used for comparison (a Jeanneau 30) was particularly tender, I give as example the 33ft from jeanneau as a boat much more stiff, even from the same line and brand
> 
> You said that the Jeanneau 30 was a good example in what regards the average stiffness of modern 30fts and I showed that you were wrong, that in fact I cannot find one as tender and posted the B/D of almost all 30ft on the market.
> 
> Paulo


Clearly comparing a 33 foot to a 30 foot boat does not make sense. On the other hand, there are 30 footers with more beam that would result in considerably more stiffness.

The problem is that you consider stiffness to be a requirement for a good rough water boat.. clearly few agree with you. And this video shows why.

In spite of the fact, the Sun 30 is probably the stiffest of the three boats for the simple reason that it is a more modern flat hull. The other two will invariably be more v-shaped less stiff hulls.

The video pretty much states what this thread is about.. even if you do not agree with it.
Bryce


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## BryceGTX

PCP said:


> Sea-kindness has not to do with the type of keel but with the hull design and boat weight (inertia).
> Paulo


Really?? I think keel design is mostly what this thread is about and keel design has been shown to be important.

BTW.. weight and inertia are radically different things.
Bryce


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## wolfenzee

A friend of mine decided to compare his Calalina 30 to my boat, same LOA, same LWL....lots of other differance....the final results surprised him 
Captian Cicero 
Ballast to weight ratio 28%
Max hull speed 6.7
Displacement length ratio 428.57
Sail area disp' ratio 13.15
Capsize screening ratio 1.42
Motion comfort ratio 46.71

Catalina 30
Ballast to weight ratio 41.18%
Max hull speed 6.7
Displacement length ratio 291.43
Sail area disp' ratio 15.17
Capsize screening ratio 1.99
Motion comfort ratio 23.99

I used SloopIT - Boat performance calculator


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## blt2ski

Do not remember which number, be it capsize or comfort ratio, but was not one of them "hood" a naval architect that came up with that ratio. Later said it was good, but at the end of the day with some of the newer designs not as useful as with past designs. Not saying that that ratio should be thrown out per say, as it favors longer/skinnier designs vs some of the fatter hulled designs of today. Rather apparent that hull design will potentially make or break a design depending upon useage as to if it will or will not work for the end user. Not just fin vs full vs bilge vs CB or some combo there of!

The more I type, I believe it is the motion comfort ratio number. Even short will come out on the lower side of things than width. As a 30'L 10' wide boat will come out with a worst number than a 60' x 20', even tho the length.width ratio is equal. I am also recalling disp being part, maybe that needs to be equally doubled to get the same ratio, where is going up double in length, usually (typically) quadruples or equal the disp of the boat. That would be an interesting plug in numbers to see what or if one can get different equal length and beam to equal.... 

Marty


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## PCP

blt2ski said:


> Do not remember which number, be it capsize or comfort ratio, but was not one of them "hood" a naval architect that came up with that ratio. Later said it was good, but at the end of the day with some of the newer designs not as useful as with past designs. Not saying that that ratio should be thrown out per say, as it favors longer/skinnier designs vs some of the fatter hulled designs of today. Rather apparent that hull design will potentially make or break a design depending upon useage as to if it will or will not work for the end user. Not just fin vs full vs bilge vs CB or some combo there of!
> 
> The more I type, I believe it is the motion comfort ratio number. Even short will come out on the lower side of things than width. As a 30'L 10' wide boat will come out with a worst number than a 60' x 20', even tho the length.width ratio is equal. I am also recalling disp being part, maybe that needs to be equally doubled to get the same ratio, where is going up double in length, usually (typically) quadruples or equal the disp of the boat. That would be an interesting plug in numbers to see what or if one can get different equal length and beam to equal....
> 
> Marty


 Hi Marty,

Many years ago, having already an interest in boat design I bought a more complete and complicated performance boat calculator the kind wolfenzee used to compare those boats and also many years ago I trough it to garbage.

That type of calculators only works with old boats and even so they have to have a similar hull shape and type of keel. The Capsize ratio ratio is particularly misleading and the comfort ratio is pretty meaningless. Jeff posted a thread about motion comfort in modern boats and posted in it also a very good article about that.

http://www.sailnet.com/forums/sailb...n/37548-modern-hull-forms-motion-comfort.html

Regarding motion capsize ratio probably the best discussion about it is on other forum but the results from the discussion are quite clear. I do not even feel the necessity to discuss that on sailnet. I guess that almost all know that the ratio does not make any sense when applied to modern hulls and by modern I am talking about 35 year's old hulls, at least the good ones.

Capsize Ratio's - Cruisers & Sailing Forums

Regards

Paulo


----------



## wolfenzee

blt2ski said:


> Do not remember which number, be it capsize or comfort ratio, but was not one of them "hood" a naval architect that came up with that ratio. Later said it was good, but at the end of the day with some of the newer designs not as useful as with past designs. Not saying that that ratio should be thrown out per say, as it favors longer/skinnier designs vs some of the fatter hulled designs of today. Rather apparent that hull design will potentially make or break a design depending upon useage as to if it will or will not work for the end user. Not just fin vs full vs bilge vs CB or some combo there of!
> 
> The more I type, I believe it is the motion comfort ratio number. Even short will come out on the lower side of things than width. As a 30'L 10' wide boat will come out with a worst number than a 60' x 20', even tho the length.width ratio is equal. I am also recalling disp being part, maybe that needs to be equally doubled to get the same ratio, where is going up double in length, usually (typically) quadruples or equal the disp of the boat. That would be an interesting plug in numbers to see what or if one can get different equal length and beam to equal....
> 
> Marty


It was Ted Brewer that thought up the "comfort ratio" Ted Brewer Yacht Design this link actually explains what the numbers mean.
"COMFORT RATIO (CR): This is a ratio that I dreamed up, tongue-in-cheek, as a measure of motion comfort but it has been widely accepted and, indeed, does provide a reasonable comparison between yachts of similar type. It is based on the fact that the faster the motion the more upsetting it is to the average person....." Not all of the ratios in those calculators are actually valid....this one actually is.

A friend of mine with a nice wide Catalina figured because my boat was much narower and shallower it would be rougher....in actual comparison and calculator agreed with each other and proved him wrong (according to the calculator is is 46.7 vs 23.9).


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## Jeff_H

As I often point out when someone tries to cite the Capsize Screen Formula and the Motion Comfort Index in that vessel's defense or prosecution (and I am about to point out yet again and apologize yet again for cutting and pasting this from an earlier post of mine) these surrogate formulas tell almost nothing about how the reality of a boat's likelihood of capsize or its motion comfort. In fact they provide so little indication of a boat's behavior that to rely on them in any way borders on the dangerous. Due to their lack of reliability these formulas have fallen into almost total disuse and disrespect amoungst practicing yacht designers. 

Both of these formulas were developed at a time when boats were a lot more similar to each other than they are today. As such these formulas have limited utility in comparing boats other than those which are very similar in weight and buoyancy distribution to each other. Neither formula contains almost any of the real factors that control motion comfort, the likelihood of capsize, or seaworthiness. Neither formula contains such factors as the vertical center of gravity or buoyancy, neither contains weight or buoyancy distribution (of the hull both below and above the waterline), the extent to which the beam of the boat is carried fore and aft, and neither contains any data on dampening, all of which really are the major factors that control motion comfort or the likelihood of capsize. 

I typically give this example to explain just how useless and dangerously misleading these formulas can be. If we had two boats that were virtually identical except that one had a 1000 pound weight at the top of the mast. (Yes, I know that no one would install a 1000 lb weight at the top of the mast.) The boat with the weight up its mast would appear to be less prone to capsize under the capsize screen formula, and would appear to be more comfortable under the Motion Comfort ratio. Nothing would be further than the truth. 

And while this example would clearly appear to be so extreme as to be worthy of dismissal, in reality, if you had two boats, one with a very heavy interior, shoal draft, its beam carried towards the ends of the boat near the deck line, a heavy deck and cabin, perhaps with traditional teak decks and bulwarks, a very heavy rig, heavy deck hardware, a hard bottomed dingy stored on its cabin top, and the resultant comparatively small ballast ratio made up of low density ballast. And if we compare that to a boat that is lighter overall, but it has a deep draft keel, with a higher ballast ratio, the bulk of the ballast carried in a bulb, its maximum beam carried to a single point in the deck so that there was less deck area near the maximum beam, a lighter weight hull, deck and interior as well as a lighter, but taller rig, it would be easy to see that the second boat would potentially have less of a likelihood of being capsized, and it is likely that the second boat would roll and pitch through a smaller angle, and would probably have better dampening and so roll and pitch at a similar rate to the heavier boat, in other words offer a better motion comfort....And yet, under the Capsize Screen Formula and the Motion Comfort Index it would appear that the first boat would be less prone to capsize and have a better motion when obviously this would not be the case.

There are some better indicators of a vessel’s likelihood of capsize. The EU developed their own stability index called STIX, a series of formulas which considered a wide range of factors and provides a reasonable sense of how a boat might perform in extreme conditions. Unfortunately meaningful results require a lot more information than most folks have access to for any specific design. The Offshore Committee of US Sailing developed the following simplified formula for estimating the Angle of Vanishing Stability (Sometimes referred to as the ‘AVS’, ‘limit of positive stability’, ‘LPS’, or ‘Latent Stability Angle’ ):
Screening Stability Value ( SSV ) = ( Beam 2 ) / ( BR * HD * DV 1/3 )
Where; 
BR: Ballast Ratio ( Keel Weight / Total Weight )
HD: Hull Draft 
DV: The Displacement Volume in cubic meters. DV is entered as pounds of displacement on the webpage and converted to cubic meters by the formula: 
Displacement Volume in Cubic Meters = ( Weight in Pounds / 64 )*0.0283168
The Beam and Hull Draft in this formula are in meters. These values are entered in feet on the webpage and are converted to meters before SSV calculation.
Angle of Vanishing Stability approximately equals 110 + ( 400 / (SSV-10) )

It should be noted that the AVS is only one indicator in evaluating the likelihood of capsize, meaning it only predicts the point at which the vessel wants to turn turtle. It does not predict the amount of force that would be required to heel the vessel to that limit, nor does it predict how the shape of the boat might encourage wave action to roll the boat closer to the angle at which it no longer wants to return.


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## souljour2000

Jeff, be that as it may be...I think you forgot the newly-devised bouyancy/draft and light displacement cross-sectional quotient theorem emanating from some of the design-boards of Europe....
....here in the states naval architects have long had a simpler term for it...wait for it...




**** ....Pounding! ****


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## wolfenzee

A friend of mine with a Catalina 30 regularly points out the good points of his boat or the bad point of mine, how some particular thing just does't work or is wrong....he does this with tools and all sort sorts things...and in every case he is right....my boat does not fit HIS application it is completely wrong for HIM.....my boat is completely right for ME though. (same goes for the tools too). A fin keel boat is without a doubt the best design...for some people, while a full keel is the best design for others (and a horse and buggy or motor home or house in the suburbs are best for someone else). Because different people have different needs and wants you can't say which is best there. Also because of the huge variety of boats that fall under each category you can not compare performance (it's sort of like comparing US designed cars to European designed cars, taking the Chevette as an example of US and the Lotus as an example of European).;
To sum it all up the ideal boat for one person might be totally wrong for another.


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## souljour2000

**To sum it all up the ideal boat for one person might be totally wrong for another**


Couldn't agree more Wolf...and it's been said before on this lengthy thread..but bears repeating...but this IS a captivating thread for the ages and though me and others may tease him... I like all the technical angles that Jeff and other keen and knowledgeable proponents bring to the table as much they offer is very educational. and illustrative of many principles in play in a moving sailboat while in my case not always quickly understood...and as I learn more...and who knows..I may indeed someday understand that Jeff or others are right about the superiority of the newer wider lighter boats in most conditions...as compared to older designs...but would still not feel I have lost the debate...perhaps to some degree because demanding shorter-term racing applications seem to be the yardstick for many who espouse the newer thinking as regards boat performance...or not..
Either way I will likely remain skeptical of higher-tech modern theory ...despite the improvements and new thinking it has brought ...especially in materials... and will do so mostly while in the support of that block of sailors who must sail older boats out of necessity in light of the economy or other reasons many in the sport face, and must thus retain a certain real and extant confidence in these earlier craft they sail ...and for good reason...as many are indeed fine boats.
So "better" is, as often is the case, a very subjective word and I expect to remain sure that the truth about superior boats lies somewhere closer to Wolfenzee's above summation...or to the effect of "...different boats for different folks..."


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## wolfenzee

Someone mentioned pounding...it's one of those features that I missed out on with my heavy disp full keel


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## BryceGTX

Jeff_H said:


> And if we compare that to a boat that is lighter overall, but it has a deep draft keel, with a higher ballast ratio, the bulk of the ballast carried in a bulb, its maximum beam carried to a single point in the deck so that there was less deck area near the maximum beam, a lighter weight hull, deck and interior as well as a lighter, but taller rig, it would be easy to see that the second boat would potentially have less of a likelihood of being capsized, and it is likely that the second boat would roll and pitch through a smaller angle, and would probably have better dampening and so roll and pitch at a similar rate to the heavier boat, in other words offer a better motion comfort....


That is your opinion.. there are many of us that would argue forever against this because we have experience with light boats and heavy boats. I guarantee, if you do not pick the heavy boat over the light boat in rough water.. ask your wife.. she will set you straight in a heart beat.

You guys that think the bulb keel is the savior of all RM clearly seem to forget that the RM is determined by the TOTAL BOAT DISPLACEMENT acting at CG of the boat through the moment arm, not the bulb hanging off the end of the stalk.

The keel mass is picked to create a particular righting moment to counteract a heeling moment. This can be achived with any keel. And it just so happens, if you put more mass on the keel at a shallower draft, you get the added weight you need to create a more comfortable boat.
Bryce


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## souljour2000

Yesterday I was watching some Fox sports video coverage of the 2012 trans-atlantic race.. quebec to St. Malo (France).

A really wide Class 40 beat out the trimaran ...makes sense since the whole race was run in a tropical depression ...their route and the depressions route were the same..so they all ran in 40-knots plus the whole way across...great video of boats um...haulin some serious azz....for thousands of miles...
...crews were wasted by end of trip as you can imagine

The "monos" did not seem to be pounding much..just surfin hard..reallly hard..I was admittedly impressed at the speeds and stability....horses for courses...but the new designs are indeed quite impressive...
The Class 40 " Campagne de France" boat that won the race set a record when it had a um... 360 mile day...while averaging over 15 knots...also seems stability and pounding seems to be getting alot better as the designs are refined...

photo below taken by Pierre Bouras


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## joebeach

This has been an amazing thread, especially for a newbie such as myself (reading its entirely over the last few days). Many modern refinements to sailboat design appear to have changed significantly the playing field for ocean-going craft in recent decades. I have the following takeaways:

1 - fin keels are faster and more maneuverable than full keels, and that makes them desirable for many types of sailing and sailors
2 - modified fin/modified full keels and keel/centerboards are legitimate way-stations along the trail of compromise endemic to boat design
3 - newer high-performance, high-aspect fin keels and associated hull designs may be as safe as traditional low-aspect full keel boats even in rough seas, but the full keel designs may still provide better options (heaving to, laying ahull, drogues) for the non-professional sailor (e.g., a cruising couple) to handle and withstand rough seas and heavy weather
4 - the science and mathematics of the dynamic stability of boats in rough seas is complex and probably still not fully understood
5 - sailors have different risk tolerances, reasons for sailing, and personal preferences that strongly affect their choice of craft, and to a great degree these subjective choices are irreconcilable should be respected as such

There is something that Jeff_H wrote fairly early in this thread that struck a chord with me and provokes a question. He wrote:

"When it comes to cruising on the cheap, there are few decent choices left out there. Many of the boats which I might have recommended 10-15 years ago were rare enough even then that the few examples available have become worn out and so are no longer good candidates.

And I find it disconcerting when I see people advocating old, short waterline, short keel, attached rudder, cruiser- racers as being good offshore capable cruisers. One of the strengths of the type of boat that you advocate is that they have very long water lines relative to their lengths on deck. This helps with motion comfort and carrying capacity. Such is not the case with the CCA and IOR based cruiser-racers of the 1960's and 1970's that I often see advocated as offshore cruisers."

So - (A) what boats are there now available for offshore "cruising on the cheap," if any, and (B) what "CCA and IOR based racer-cruisers" should be avoided for that purpose?


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## outbound

Awesome thread- Been puzzling about this for last 30yrs. with more thought in last 5 as I needed to decide on my "last" boat. There are some basic physics which I don't see stressed in the posts.
Modern boats go faster. A modern racing mono hull commonly is above 10kts. Compare the wings of biplane to a jet. As speed goes up you need a flatter foil with less chord and higher aspect. For older boats moving at hull speed or below full or fin can be argued. For modern or even semi modern cruising mono hulls full keels fly in the face of basic physics. As one increases speed and decrease the horizonal length of the keel you may decrease directional stability. This may be further modified by sailing on the chine and the wide stern with little V of modern boats. This may raise the need for daggerboards and additonal complexity. Steering may require dual rudders adding yet more complexity. Many of us think we want a monohull that will take care of us not a multihull we need to take care of in a storm. That being the case many of us choose a high aspect fin with bulb and balance spade rudder of strong construction but don't go to the limits of a Boreal, class 40 or other boats requiring multiple levels of complexities to be sailed "correctly". 
There also has been little discussion of the "diagonals" and other features of hull shape on comfort. I been on several boats where the wide stern may have worked under sail but at anchor were noisy, skated around and unpleasant.


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## PCP

outbound said:


> .... Steering may require dual rudders adding yet more complexity. Many of us think we want a monohull that will take care of us not a multihull we need to take care of in a storm. That being the case many of us choose a high aspect fin with bulb and balance spade rudder of strong construction but don't go to the limits of a Boreal, class 40 or other boats requiring multiple levels of complexities to be sailed "correctly".
> There also has been little discussion of the "diagonals" and other features of hull shape on comfort. I been on several boats where the wide stern may have worked under sail but at anchor were noisy, skated around and unpleasant.


A Boreal is very easy to sail and very seaworthy.

http://www.voiliers-boreal.com/

Dual rudders come to stay. They did not only make possible the use of much less deep rudders as also provide a bigger safety margin not only because they are smaller (and less deep) and therefore subject to less stress but also because they are two and even without one is possible to sail the boat (slowly) back home. They are not only safer as they also provide better control of the boat, specially in what regards beamy boats. It is a need on those, but even on boats with moderate beam they increase control and directional stability.

Regarding beam and safety it is better not to forget that tank testing showed that there was a relation between the beam of a boat and the breaking wave needed to roll it. That's why multihulls are much more difficult to capsize by a breaking wave than monohulls (and the opposite regarding wind).

The trick with modern boats is to increase the capsize resistance (and the boat power) without diminishing the reserve stability, providing a good AVS and an inverted stability several times smaller than the positive stability. That is, joining the good stability characteristics of multihulls with the good stability characteristics of monohulls (reserve stability and possibility to re-right the boat).

For that beamy boats have to have a very low CG. That's why you have seen on the last years, with the increase of beam a correspondent increase of draft and the proliferation of torpedo keels with all ballast at the bottom of the keel. Draft is also a way of increasing directional stability.

Of course, not all beamy boats are alike and I would suggest that before buying one a good look at the stability curve is a must, to see if the reserve stability, a good AVS and a proportional smaller inverted stability are part of the deal.

Regards

Paulo


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## wolfenzee

Marketing relies on people thinking"If I take features found on racing boat and put them on a cruising boat it will make it faster"....not sopping to think that all of those racing attributes make boats harder and more complicated to sail as well as more expensive. In a cruising boat you should look for simple efficiency. If a boat takes work and/or is tiring to the crew at sea that can be dangerous....fatigue is one of the most dangerous things at sea.


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## Lou452

Still my favorite thread. Can I ask about the Contessa 32 ? A long fin keel ? Good day, Lou


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## wolfenzee

I like this thread, but it is also an example of how people generalize. My boat was designed by William Atkin, who's designs were also used in the West Sail (sometimes called a "West Snail"). Sitting side by side on the hard they look noticeably similar, but the West Snail appears "pudgy" and in comparison, my boat is downright "sexy". My boat has a transom and if the lines were continued to a double end would be the same size my 30' has a 25'lwl and the West Sail 32 has a 27'lwl, but the beam is only 80% of the West Sail. 
My full keel is fast and does maneuver well. My point being that two very similar boats can be very different in performance.


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## PCP

Lou452 said:


> Still my favorite thread. Can I ask about the Contessa 32 ? A long fin keel ? Good day, Lou


Contessa 32 are fantastic boats that even by today parameters have a good performance upwind, specially in bad weather.

I will reply another way:

This is Babe, a famous S&S design and a great boat:



















The boat was almost a S&S icon so S&S decided to produce the boat again with the same basic dimensions:










Do you notice any difference

Regards

Paulo


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## Lou452

I will show how little I know in hopes of learning Yes the rudder and keel have changed a lot. the bulb on the bottom of the keel and how much deeper the rudder. Twin rudders seem to be up and comming? The full keel is less in demand. I will just assume the Contessa 32 is very good in rough seas ? Her history after the 1979 Fastnet leads me to think this way. It could be she was with a great crew. 
I hear so much about sea motion and heaving-to and how a fin will not be able to. I am trying as new sailor to sort out time proven boats and look to design transition between cutting edge and traditional this is where my dollar and building skill level will bring the best return. 
How does one judge skill vs the (the boat taking care of lack of skill) 
It will be some time before I move up in boat size the jump this year is from a flying junior at 13' to a Catalina-22 So I have no fin/full keel experience
I so much enjoy this thread Thanks PCP and Wolf Good day, Lou


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## wolfenzee

As my boat was designed 75 year ago there are alot of aspects of hull and rig design that are considered to be "obsolete" "antiquated" and "ineffiecient" (they must be ineffiecent because they don't use them anymore). But even so the boat is fast, points well, handles nicely on all points of sail etc....it's just a matter of vintage (newer must be better and older must be bad)....that is not true.

Another thing people keep forgetting...the original intention of this thread was to ask about the difference in comfort between a full keel and fin keel in blue water conditions, but has evolved into a debate about performance....lumping all fin keels in one catagory and all full keels in another, which is incredibly inaccurate.


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## PCP

wolfenzee said:


> ...
> 
> Another thing people keep forgetting...the original intention of this thread was to ask about the difference in comfort between a full keel and fin keel in blue water conditions, but has evolved into a debate about performance.......


Where do you get that these thread was about comfort? this was the first post and the original question:



utchuckd said:


> Can somebody pro/con a full vs. fin keel for a newbie (will learn to sail on said boat) and taking it thru the Caribbean? ...


Performance in a sailboat means basically how well a sailboat sails. Speed and sailing ability are two of the most important factors. Don't you think that it is to be considered regarding the pros and cons?

Regarding motion it has essentially to do not to fin keel or full keel but with Displacement/Length. It is true that generally the full keeler are heavier but not always true. Some full keel boat are also relatively light and some fin keel boats are heavy.

Anyway regarding motion it was already well established in other threads about the subject that some prefer the slow but deep pitching of an heavy boat to the sharper but less accentuated movements of a lighter boat and vice verse.

Regards

Paulo


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## outbound

so at the end of the day it's

Whatever floats your boat ( grin).


Still think the Wolf is right there are special boats that are drawn in every vintage where the magic of balancing performance,comfort, beauty and safety are achieved. Unfortunately you generally don't know if you have such a vessel until you have owned it for some time and have put through all it's paces. At that point Paulo is looking at the next major advance.


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## PCP

Outbund I have owned a boat that today would have 86 years and whose design come from centuries ago. I understand the pleasures of vintage boats and the pleasure of sailing them. But those pleasures have nothing to do with the pleasures of sailing in a better sailboat, in a sense it just sails better, rather with the pleasure of simple things and enjoying the sailing as it was done for centuries, in a very simple way.

For truly enjoying that pleasure, the pleasure of simple things and to be in accordance with the boat one should sail with the minimum necessary, that is a Compass, a sighting compass and binoculars and preferably with just a small outboard or if one is good enough, without an engine at all.

I understand well those pleasures because I lived them.

But if one wants to cruise in the summer several thousands of miles (there are so many things to see, so many places to be) and want to do it sailing the best is to have a boat that can sails easily to 7.5K and that in good conditions can go at 8/10K, a boat that needs only 4K wind to make an acceptable speed and use a plotter, a radar and all the good stuff that fits well with that kind of boat.

For that it is better a modern boat, that in some cases it can even look a classic but has a modern under-body, for instance one like this:






Different pleasures, different boats and sometime the same people enjoying both.


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## Lou452

outbound said:


> so at the end of the day it's
> 
> Whatever floats your boat ( grin).
> 
> Still think the Wolf is right there are special boats that are drawn in every vintage where the magic of balancing performance,comfort, beauty and safety are achieved. Unfortunately you generally don't know if you have such a vessel until you have owned it for some time and have put through all it's paces. At that point Paulo is looking at the next major advance.


Yes but time and money are in the game. It would be nice to get it right on the first try. The magic balance. The main use of a boat rules the day. I say once agian I like this thread. I will have to make a choice some day. Good day, Lou


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## PCP

Lou452 said:


> Yes but time and money are in the game. It would be nice to get it right on the first try. The magic balance. The main use of a boat rules the day. I say once agian I like this thread. I will have to make a choice some day. Good day, Lou


Yes, but in what regards an old used boat the the type of keel may have not a big play on that choice. it is more important the type of boat you want (and that may not necessarily have to do with the keel unless it is a shallow draft center-boarder). There are some old keel boats that are faster and point better than some fin keel boats. It all depends on the money you have and the choices and deals you can find.

First you have to see what is your budget and then you need to see how and for what you are going to use the boat, in what waters (swallow waters, protected waters, coastal, offshore occasionally, extensively offshore), for how many people, to live aboard or to cruise in the summer and with that criteria there are here guys that know very well the American used boat market and that can point you on the right direction regarding the boats you should look for and I don't think the type keel would have a big relevance.

Trying to know if it is going to be a fin keel, a modified fin keel or a full keel is starting on the wrong end of your search, in what regards a considerably old used sailboat.

Regards

Paulo


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## wolfenzee

Lou452 said:


> Yes but time and money are in the game. It would be nice to get it right on the first try. The magic balance. The main use of a boat rules the day. I say once agian I like this thread. I will have to make a choice some day. Good day, Lou


I did get it right the first try, as far as money purcase price was $17,500...the boat was strip plank finished with fiberglass (later replace with fiberglass using epoxy resin)...so I don't have any of the problems related to wood boats. Previous owners (as well as the designer) knew what they were doing so the rig was tweaked for performance. My life's knowledge of sailing has helped me to tweak it more. Even though I have been sailing all my life, this is my first boat I didn't have much money and didn't look around much.....just stumbled into it and got it right the first time.


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## dorymate1

A lot of very complex answers to a very simple question. Fin keels that are bolted on can fall off or be knocked part way off and leak. Full keels and encapsulated keels with rudders behind skegs will make better long range criusers. Will be better @ bouncing in & out of unfamiliar gunk holes. If you want to beat me there however go for the fin. I'll eventually show up with a pump for you.


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## Lou452

Thanks once more for the advice. I can see you need to know what the plan of use is before you can buy the right boat.
For now I have the right boats for me. The FJ was a step up from the sunfish It will still get in the small shallow lakes two meters 6-feet deep 1/2 hour away. Two lakes close by I can go after work. The other boat is a swing keel Catalina-22 I can take it to the (big lake) two hours away. I can spend the night and dream about fin vs full keel. Like many in the USA. I dream of the Keys and the Virgin Islands, This means a gunk hole boat. Then with more know how we will have to see if we want to go on a voyage. 
First I need to learn to sail proficiently and navigate. Right here inland in Ky sailing is a challenge. Learning about boats is a lot of fun. Good day, Lou


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## outbound

Comments are interesting
Dory mate- My new boat has a 6 1/2' high aspect fin keel. It is laid up as part of the hull. Bottom is filled with lead. Then two formed pieces of lead are through bolted through the fin and in to each other at the bottom. Then the entire bulb is heavily glassed over. The structure is further supported by a grid inside the hull. In short going at hull speed or above given how overbuilt the keel and hull are IT AIN"T GOING ANYWHERE. The bow may go under water and I may go flying but I'm not worried about the keel falling off. Similarly the balanced spade rudder aint going anywhere. Massively over built.I've seen alot of boats where the rudder was holding the skeg on.Or the shoe bearing on a full keel boat was just for looks. A lot of the old saws are ridiculous. A poorly made boat is poorly made and the contrapositve is equally true. Full keel / fin keel has nothing to do with it. I previously had a full keel boat. Made in China. Given the way the KEELBOLTS were done on that boat I did worry and ended up re working them. Have been on encapsulated ballast boats where the ballast was working inside the cavity. Scared the crap out of me. Had no sleep and blue eyes by the end of that trip.

Paulo-Friend owns a company that sells high performance multihulls. To get my wife into cruising wanted her to see you could get there fast. She was a liveaboard on a motorboat as a child for awhile. I thought she would not like life on a slant or island time. He gave me a tri for a week.First day pulled up the rags. Rgging was singing so loud is was hard to talk even yelling and the tiller was buzzing into your hand as the high speed cause rudder cavitation to make it necessary to switch hands as they got numb. Trimmed her up and approached warp speed. I had a big grin but she started to cry. Sailed the rest of the week with just the main and rarely a scrap of jib for balance.

Have come to believe there is a comfort to be one step behind cutting edge. There's a reason sailors in general and people like me spending their kids inheritance are conservative. There's a reason the recent multiple million dollar one offs coming out of Maine and North Carolina have single rudders. One is even a ketch.
Boreal makes a great boat. When it came down to 3 boats it was in the mix. Couldn't get past having the anchor chain in the middle of the boat. Decided I rather have all my fuel and water there to improve gyradius and not have the stink and clink. Could not get past the European galley. (Although he has redone that since.) Didn't want to attend to electrolysis in the harbors I frequent where stray current is a given. Gotten to an age where it still upsets me to see a boat sailed poorly but want a boat that's easy to sail well. Broad light boat made of unobtainium sails on top of the water not in it. Sure it's fast (p.s.- my boat is no slow poke) but how are you going to feel about it 10-15 years down the road. Hope to stick around and see how it goes.

sorry about venting at such great length. Boy did it feel good


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## PCP

dorymate1 said:


> ... Fin keels that are bolted on can fall off or be knocked part way off and leak..... If you want to beat me there however go for the fin. I'll eventually show up with a pump for you.


Jesus


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## PCP

outbound said:


> ..
> Paulo-Friend owns a company that sells high performance multihulls. To get my wife into cruising wanted her to see you could get there fast. She was a liveaboard on a motorboat as a child for awhile. I thought she would not like life on a slant or island time. He gave me a tri for a week.First day pulled up the rags. Rgging was singing so loud is was hard to talk even yelling and the tiller was buzzing into your hand as the high speed cause rudder cavitation to make it necessary to switch hands as they got numb. Trimmed her up and approached warp speed. I had a big grin but she started to cry. Sailed the rest of the week with just the main and rarely a scrap of jib for balance.
> 
> Have come to believe there is a comfort to be one step behind cutting edge. There's a reason sailors in general and people like me spending their kids inheritance are conservative. There's a reason the recent multiple million dollar one offs coming out of Maine and North Carolina have single rudders. One is even a ketch.
> Boreal makes a great boat. When it came down to 3 boats it was in the mix. Couldn't get past having the anchor chain in the middle of the boat. Decided I rather have all my fuel and water there to improve gyradius and not have the stink and clink. Could not get past the European galley. (Although he has redone that since.) Didn't want to attend to electrolysis in the harbors I frequent where stray current is a given. Gotten to an age where it still upsets me to see a boat sailed poorly but want a boat that's easy to sail well. Broad light boat made of unobtainium sails on top of the water not in it. Sure it's fast (p.s.- my boat is no slow poke) but how are you going to feel about it 10-15 years down the road. Hope to stick around and see how it goes.
> 
> sorry about venting at such great length. Boy did it feel good


Regarding fast Trimarans comparing with monohulls, they have less interior space but they are way faster. Comfort on a boat is most of the time a function of speed. As a 70 year older trimaran sailor said to a friend of mine regarding comfort: "I can go slower but you cannot go faster". It is all related about what you want on a sailboat and the importance that was to you sailing fun. You said that you were grinning while sailing the tri: That's about that and be able to cruise while grinning

Regarding that story about holding the tiller, cruising trimarans and even solo racing ones are designed to go on autopilot as any other boat and will have no problem with that. They are very stable on a course.

Regarding aluminium boats and electrolysis that only happens to boats made by amateurs that don't understand the specific needs of the boat electrical set up. The French have thousands of shipyard made Aluminium boats (for 40 years long) and have no problems with that.

Regarding rudders and big yachts. I would say that sailboat design is more advanced in Europe than in the US, if we forget about Farr that is not an American. Given an example how US boats are made in what regards something that is a recent development is not relevant. Here many big yachts are already made with twin rudders and more will come. They offer a lot of advantages, mechanical, regarding efficiency and improved safety. I have no doubt that they come to stay and you are going to see an increase of use in mass produced boats.

Regards

Paulo


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## outbound

Paolo- I have every respect for you and your knowledge base. There is not a piece of Dacron in any of my sails( except the trysail and stormjib). All my running rigging is "no stretch". My blocks are soft shackles. But that doesn't mean I would ever want a boat with hard sails and a hinge in the middle or that goes so fast a windvane won't work on it or with appendages so prone to picking up all the junk now in our oceans that I take comfort in having another one. I can live with 6'6" and don't want a Swan/Baltic with it's keel on hydralics. Neither do I want a monhull or multihull whose perfomance will be ruined by the extra weight in stuff we collect when cruising. I like carrying the extra water/fuel/central heat/air/washerdryer/third anchor and rode/spares for everything etc.Similarly a boat made of exotics then baked in a huge oven doesn't interest me. I want a boat any decent yard can maintain and fix. Not just a few at great expense. I'm not a Luddite but know sooner or later I or my crew will be inattentive or something will break (rudder sensor on the Autopilot, lighting and all electronics go down etc.) or GIRBs will be misread. Then I want a boat that will accommendate our human frailities and stupidity and still get me to a safe harbor. I also know Bill Crealock was right. The pleasure of the voyage should at least equal the pleasure of the arrival. There's a point where you are right physically but wrong metaphysically- the boat goes faster- but at what cost to the wallet, time in maintenance, experience of comfort, complexity of systems and sense of safety. Thank you- I'll stay in the front of the pack but too often the pace settor doesn't win the race.


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## PCP

outbound said:


> Paolo- I have every respect for you and your knowledge base. *There is not a piece of Dacron in any of my sails*( except the trysail and stormjib). All my running rigging is "no stretch". My blocks are soft shackles. But that doesn't mean I would ever want a boat with hard sails and a hinge in the middle or that goes so fast a windvane won't work on it or with appendages so prone to picking up all the junk now in our oceans that I take comfort in having another one. I can live with 6'6" and don't want a Swan/Baltic with it's keel on hydralics. Neither do I want a monhull or multihull whose perfomance will be ruined by the extra weight in stuff we collect when cruising. I like carrying the extra water/fuel/central heat/air/washerdryer/third anchor and rode/spares for everything etc.Similarly a boat made of exotics then baked in a huge oven doesn't interest me. I want a boat any decent yard can maintain and fix. Not just a few at great expense. I'm not a Luddite but know sooner or later I or my crew will be inattentive and something will break (rudder sensor on the Autopilot, lighting and all electronics go down etc.) or GIRBs will be misread. Then I want a boat that will accommendate our human frailities and stupidity and still get me to a safe harbor. I also know Bill Crealock was right. The pleasure of the voyage should at least equal the pleasure of the arrival. There's a point where you are right physically but wrong metaphysically- the boat goes faster- but at what cost to the wallet, time in maintenance, experience of comfort, complexity of systems and sense of safety. Thank you- I'll stay in the front of the pack but too often the pace settor doesn't win the race.


Well, as I said, different boats for different sailors. For instance, I, that actually sail about 100 days a year on a sunny climate, don't want any laminated sails, that means I have to live with them (that's what I have in my boat now) but as soon as I can get I would change to top woven sails and that means high quality dracon.

That does not mean that laminated sails are not good for cruising, even sailing 100 days a year in the sun. They certainly provide a better performance and if one can change them each 2 years they would be very appropriated. That is not my case. I need sails that last at least 6 years *on those conditions *and that means dracon sails. If I had the extra money for more expensive sails and to change them each 2 years, I would take a different option. Each case is a case and what is god for one may not be to another.

You seem to make the assumption that modern boats are less safer than older boats and even if each case is a case, globally it is quite the contrary.What is certainly true is that modern boats are faster and sail better than old boats, so I quite don't get your point. It seems that you consider all modern boats as radical and race boats.

They are for all tastes and the good ones in each "taste" represents the state of the art in what regards design and sailing ability. For instance the twin rudders and chines (the way they are used) are an innovation that comes from racing research but all boats can benefit with that and today many cruisers, including voyage boats have them. That just makes them better sailboats without any other disadvantage and in the case of the rudders with further mechanical and safety advantages. Same thing with the transom design and beam being pulled aft. They increase boat control downwind and therefore make the boats safer and more easy to go downwind on autopilot.

Regards

Paulo


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## dorymate1

Out bound sounds like your keel is on there. But suggest you walk around those New England yards and see just how many of those fin keels are jammed up into the hull @ the trailing edge.


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## outbound

Dory- once again it depends on the quality of the initial construction. Suggest you look at the construction of many modern boats. Paolo is right -they have learned with time. When the expense is paid in design time, materials and labor modern boats are stronger and safer then ill constructed older vessels. I see you work in a very distinguished yard. Think about the boats you have seen fail. Suspect most are coastal crusiers that would not meet the CE A classification the boats have that Paolo is talking about. Even with CE A there are poorly engineered boats. ?Have you seen any Morris, Passport, HR, Nautor, Hlylas, Baltic,Rustler, Outbound, Malo, etc. where that's happened?
Paulo- My point which you yourself said in this and other threads is
In the quest for speed monohulls have gotten broader , lighter and deeper. As this trend continues it is more dificult to find an ultra modern boat that is not unduelly sensitive to weight brought on board, pleasant to sail and live on and easy to maintain. You are right beyond comfort quoients and other parameters at a certain point speed becomes the enemy of the total experience for the cruiser. As the N.A.s move forward that speed point becomes greater but there is a point where the trade off is unacceptable to most cruisers.. I could ride a Duc or Benelli but rather ride a WIng. I go much further in a day. The crouch rockets are faster and have orders of magnitude greater technology ( slipper cutches, ultra ligh billet and components) than the Goldwing. I could ride a Harley but rather ride a Wing. I'm not a luddite ad realize simple physics says a water cooled engine can outperform an aircooled one just like fin does better than full when done right. I like to have breakfast in one state lunch in another dinner in a third and still have the energy to snuggle the wife that night. That's my point. There is a segment of the cruising public where the latest and greatest just doesn't make sense for how they use their boats neither do old school designs.. The offerings for the segment of long term cruisers has gotten smaller and way more expensive.


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## Tranquilo

OK, dumb question, but it won't be my first or last... is a winged keel, and fin keel one in the same?


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## PCP

dorymate1 said:


> Out bound sounds like your keel is on there. But suggest you walk around those New England yards and see just how many of those fin keels are jammed up into the hull @ the trailing edge.


Do you have any evidence that the loss of the keel is a problem on the boats that use fin keels, even mass production ones?

Regards

Paulo


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## PCP

Tranquilo said:


> OK, dumb question, but it won't be my first or last... is a winged keel, and fin keel one in the same?


In the way they are attached to the hull yes. We can say that a winged keel is a modified fin keel.

Regards

Paulo


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## fallard

Another consideration might be a centerboarder, which is typically a hybrid, in effect.

Open water isn't a concern, but there are places where you might appreciate shallower draft than a traditional fin keel may offer. 

I would also second the motion by Faster that maneuverability in tight quarters is a drawback for the full or modified full keel boats. I've had plenty of experience with charters in this regard--mostly with Island Packets (modified full keel), but also with Beneteaus, Jenneaus, Wasquiez, Sabre in the fin keel genre. 

My own boat is a swing keel (fin) that is very maneuverable when the keel is down in close quarters. With an elliptical keel (not a high aspect ratio fin) my boat does well on all points of sail and is particularly weatherly. My boat is also a lot more fun to sail than a full keel boat because of its weatherliness and responsiveness.


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## outbound

Believe the properly designed centerboarder is a joy. Another way to adjust point of lateral resistance and of reducng draft at will are blessings. Still even with well executed designs have had some bad experiences. Irregular noise as the boat rolls in quartering seas on a trip back from Bermuda kept the crew from sleeping soundly ( Boat was a Hinckley). Jammed from gravel some how while crossing from Southwest Harbor to P town (boat was a Seguin if I remember - still don't understand how that happened - boat was nowheres near shoal water at anytime-was told needed a haul to clear). Regardless of how well done it's difficult to get a elliptical keel to have as effective hydrodynamics as a dedicated fin ( chord will vary as deployed and usually low aspect) and of course a bulb is a more effective lever arm than even a weighted board and internal ballast. Paulo mentions the Boreal and course there are the Southerlies and Ovnis making good use of this technique at present. Never had the pleasure of owning one but sure have had frustating days helping friends maintain them and their trunk/pendant and pin.Wish you joy of her Faster. Agree your decision is a excellent one on the east coast but looking at noon to noons thought to go a different way.


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## PCP

outbound said:


> Paulo mentions the Boreal and course there are the *Southerlies* and Ovnis making good use of this technique at present...


Southerlies are different. They don't have all the ballast on the swing keel but have a lot of ballast on it.

An then you have the most recent evolution, boats with a swing keel that can go till 3.0m with all the ballast on the keel. These ones have the advantages of boats with fin ballasted keels and the advantages of centerboarders. There are two members with two of these (fast) cruising boats, one with a Pogo 12,50 other with a Wauquiez Opium 39, both very satisfied with their boats, and it seems to me that more are inclined that way.

Regards

Paulo


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## Faster

fallard said:


> .....
> My own boat is a swing keel (fin) that is very maneuverable when the keel is down in close quarters. With an elliptical keel (not a high aspect ratio fin) my boat does well on all points of sail and is particularly weatherly. My boat is also a lot more fun to sail than a full keel boat because of its weatherliness and responsiveness.


fallard, I see you've got a Clearwater... always liked that boat/concept. That's actually 2 SNers (CapnRon47? I think) with that boat - kinda neat because they're not that common.



outbound said:


> Believe the properly designed centerboarder is a joy. Another way to adjust point of lateral resistance and of reducng draft at will are blessings.......


Interesting, though, that ErikLYC, a new owner of a brand new centerboard boat, tells us his keel is only usable/structurally stable in the fully deployed position, which takes away that 'adjustable CLR' feature.



outbound said:


> .Wish you joy of her Faster. .


Thanks but that's not me!!


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## Jeff_H

Tranquilo said:


> OK, dumb question, but it won't be my first or last... is a winged keel, and fin keel one in the same?


No they are not the same. A wing keel is a type of bulb which minimally is supposed to act as a end plate and in extreme cases work as a wing when the boat is heeled. By traditional definition. A fin keel is any keel with a bottom less than 50% less than the length of the boat . In more modern usage, it's a keel in which does not have an attached rudder.


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## chris_gee

Some brief comments on the Contessa 32 since it has come up. Yes in effect the keel is in between, it has a skeg hung rudder and overhangs. It is an excellent sea boat, and sails well. It likes a bit of heel and can throw up a bit of spray which is easily overcome by a couple of strakes or rubbing rail on the bow.
It is relatively narrow so is less fast downwind than one with the beam carried aft but is more stable. The downside is less internal volume so one sure would not be trying to fit 6 in more like 2 or 3 max on a passage. However that is true for most boats of that length, particularly when you think of storage extra sails etc. 
Being relatively narrow plus having easily accessible handholds makes it safer in a seaway versus being tossed from side to side.
It might be said to be a bit harder to dock than a fin keel but with a bit of practice it is not difficult.
A number of factors interact in choosing a boat, money, comfort, crew numbers, prevailing weather, ease of handling, intended use. Personally I rank the security of having a good sea boat highly. Sure it has to sail well but speed for a non-racer is not the dominant factor.


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## flandria

OK. Good stuff given so far. One point to keep in mind; if you decide to go with a fin keel I suggest you do NOT get a wing keel, just to get a more shallow draft. Since you will run aground at some point in time, the wing keel severely limits your options on getting yourself back afloat. (Yes, I have wing keel now, haven't been in trouble, but would not again get a boat with such a keel). The comments about the manoeuvrability of a fin keel in close quarters, compared to full keel, are not to be ignored. You'll thing of them whenever you visiting a marina (which will be unknown territory in many cases) - both when coming in (forward, let's assume) and leaving (backing out).

Best of luck with your eventual purchase!


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## outbound

Fallard I deeply apologize to you and Faster. Think neither should be confused with each other but neither should hopefully be offended when an slow witted dyslexic like me does it.


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## PCP

Faster said:


> ...
> 
> Interesting, though, that ErikLYC, a new owner of a brand new centerboard boat, tells us his keel is only usable/structurally stable in the fully deployed position, which takes away that 'adjustable CLR' feature.


That is because Eric's boat is a Pogo 12.50, one of those that has a swing keel with all the ballast on the keel.

That creates different problems than on non ballast centerboard in what regards lateral forces. The keel has to be on the proper place to not move latterly face to the big forces on the head of the keel when the boat is heeled.

Eric also says that once in place even with waves and bad weather the keel does not have any movement. I guess that would not be possible with the keel half way, without being locked in the place.

Regards

Paulo


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## fallard

outbound said:


> Believe the properly designed centerboarder is a joy. Another way to adjust point of lateral resistance and of reducng draft at will are blessings. Still even with well executed designs have had some bad experiences. Irregular noise as the boat rolls in quartering seas on a trip back from Bermuda kept the crew from sleeping soundly ( Boat was a Hinckley). Jammed from gravel some how while crossing from Southwest Harbor to P town (boat was a Seguin if I remember - still don't understand how that happened - boat was nowheres near shoal water at anytime-was told needed a haul to clear). Regardless of how well done it's difficult to get a elliptical keel to have as effective hydrodynamics as a dedicated fin ( chord will vary as deployed and usually low aspect) and of course a bulb is a more effective lever arm than even a weighted board and internal ballast. Paulo mentions the Boreal and course there are the Southerlies and Ovnis making good use of this technique at present. Never had the pleasure of owning one but sure have had frustating days helping friends maintain them and their trunk/pendant and pin.Wish you joy of her Faster. Agree your decision is a excellent one on the east coast but looking at noon to noons thought to go a different way.


Several comments:

1. The Sequin 40 (if that's what is was) was designed by Craig Walters and looks like a bigger version of my Clearwater 35, also a Walters design. The Clearwater 35 has 2500# of lead ballast inside the leading edge of the NACA shaped keel, according to Barrett Holby, the builder. (An additional 2500# of lead is glassed into the rather slack bilge.) i would estimate that my swing keel is pushing 3000#. It's hard to imagine jamming the keel in its trunk due to gravel or mud, as can be the case with a conventional centerboard. I am assuming the Sequin 40 has a larger version of my ballasted keel, so its hard to imagine jamming it.

2. The Sequin 40 and Clearwater 35 are not true centerboarders. the bottom is whaleback-shaped and there is no stub keel , which allows them to be beached like a Southerly. The lack of a keel means my draft is 1' 10" with everything up (including the rudder). You could sail my boat like a centerboarder by varying the amount of keel down, but that leaves the trunk slot open and would produce turbulent flow. When the keel is all the way down, the trunk slot is closed. If I am in deep enough water, and can live with a 5' 11" draft, I leave the keel all the way down. BTW, the PHRF rater had my displacement at 12,500#, despite what the spec sheet below says.










3. The elliptical keel is a compromise. Aside from the difference in waterline length, some folks compared the Clearwater 35 (on paper) to the J-35, which has a more hydrodynamically-efficient fin keel. When the PHRF folks got through and there was an opportunity to compare them on the water, it was quite clear that the fin keel made for a faster boat--that and a ton less weight, longer LWL, and 20% more sail area for the J-35.

4. My offshore experience is limited, but we made the 600 mi. from Ft. Pierce, FL, to Beaufort, NC, in 72 hours, sailing all the way until within sight of Emerald Isle, when the wind died down. We went offshore to get the Gulf Stream boost, but that's still good time, and the boat motion was easy. So, I don't think our speed compared to LWL needs any excuses. Also, we won our very first race (cruising category) in a field of 13 or so other boats, including a Cardinal 46 that has participated in the Newport Bermuda race. We won it in actual as well as corrected time, perhaps because we outpointed every boat in the fleet when it mattered. Unfortunately our racing career went downhill after that!

5. Our maintenance issues with the swing keel have been minimal. We replaced the 1.5" dia, pin after noticing pitting corrosion at the seals. The original appeared to be 304 SS, whereas the replacement is 316 SS and is going on 13 years with no problems. I've replaced the nylon pennant once, on a precautionary basis. The retractable rudder was more troublesome until we replaced the original aluminum rudder trunk with a composite structure to eliminate binding. Overall, maintaining this retractable system has not been much of a problem once we fixed the items mentioned.

One last comment, another keel type to consider is the retractable, weighted daggerboard that is used in the Hake designs. You've got an efficient foil shape, ballast bulb to keep the CG low, and you also have shallow draft when you need it.


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## fallard

outbound said:


> Fallard I deeply apologize to you and Faster. Think neither should be confused with each other but neither should hopefully be offended when an slow witted dyslexic like me does it.


outbound: Absolutely no offense taken. Faster seems like a cool guy, so the confusion is actually flattering.


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## outbound

Fallard- beautiful vessel. You're obviously right. My memories of events 25+ years ago are faulty. Boy getting to apologize alot to you today.Didn't some of Hoods play the same trick. Using both the canoe body and centerboard in harmony to achieve weatherliness and with slack bilges a very pleasant motion.


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## Faster

fallard said:


> outbound: Absolutely no offense taken. Faster seems like a cool guy, so the confusion is actually flattering.


Ditto, and back at you fallard!


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## fallard

outbound said:


> Fallard- beautiful vessel. You're obviously right. My memories of events 25+ years ago are faulty. Boy getting to apologize alot to you today.Didn't some of Hoods play the same trick. Using both the canoe body and centerboard in harmony to achieve weatherliness and with slack bilges a very pleasant motion.


One of the candidates when I was searching for a boat in the '95 timeframe was the Bristol 35.5, a Ted Hood Design. I had actually sailed one during a 5 day 'guys' cruise in the Great Lakes. The 35.5 is heavier than my Clearwater by over a ton, but has sail area proportional to displacement and has almost the same beam. However, it has a fairly effective, shallow, modified full keel and can be sailed without the centerboard down, except for beating, if you want to be lazy. It's a solid boat, but the pennant system for the CB is "interesting"--not nearly as straightforward as you'd like. The shallow keel requires twice as much water as my Clearwater and, consequently, the 35.5 would not do well to stay at my shallow water dock (~4' draft and 2.5' at MLW).

The one feature feature that does stand out is how tender the 35.5 is compared to my Clearwater. My boat obviously has more form stability and may have been fairly well-designed to achieve a weight discipline in that regard. As the admiral says, heeling over much more than 15 degrees isn't making us go any faster. I recollect that the 35.5 would be at 20 degrees before reaching that point, which makes it harder to move our senior bones around.

That said, if my Clearwater (the last 35 built) hadn't become available I might be sailing a Bristol something or other designed by Hood.


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## wolfenzee

outbound said:


> Paolo- I have every respect for you and your knowledge base. There is not a piece of Dacron in any of my sails( except the trysail and stormjib). All my running rigging is "no stretch". My blocks are soft shackles. But that doesn't mean I would ever want a boat with hard sails and a hinge in the middle or that goes so fast a windvane won't work on it or with appendages so prone to picking up all the junk now in our oceans that I take comfort in having another one. I can live with 6'6" and don't want a Swan/Baltic with it's keel on hydralics. Neither do I want a monhull or multihull whose perfomance will be ruined by the extra weight in stuff we collect when cruising. I like carrying the extra water/fuel/central heat/air/washerdryer/third anchor and rode/spares for everything etc.Similarly a boat made of exotics then baked in a huge oven doesn't interest me. I want a boat any decent yard can maintain and fix. Not just a few at great expense. I'm not a Luddite but know sooner or later I or my crew will be inattentive or something will break (rudder sensor on the Autopilot, lighting and all electronics go down etc.) or GIRBs will be misread. Then I want a boat that will accommendate our human frailities and stupidity and still get me to a safe harbor. I also know Bill Crealock was right. The pleasure of the voyage should at least equal the pleasure of the arrival. There's a point where you are right physically but wrong metaphysically- the boat goes faster- but at what cost to the wallet, time in maintenance, experience of comfort, complexity of systems and sense of safety. Thank you- I'll stay in the front of the pack but too often the pace settor doesn't win the race.


The boat I have has a very flexible 47' 3-piece laminated Sitka Spruce mast with a low tension rig, using relatively stretchy 1/4" 7x19 wire(6 shrouds, 3 stays and running backs)....this allows for significant mast bend and sail shape adjustment (designed this way 75 years ago)......if I put rod rigging and hard sails on her it would break the boat.


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## outbound

Another keel that always appealed to me was the work of Henry Scheel. I think best put to use on the Cheribini s. Narrow as a knife. 44- a ketch 48 -a stays'l schooner but both full keelers could go to weather like a witch.Well past hull speed. Looks to be a wet boat - but never sailed one so don't know. Bet she would have a solid ride. Put together right and drop dead gorgeous. There were two 44's in my prior harbor(Marion). Would stop even a speedfreak's heart to see them zipping around Buzzards Bay. Believe one of Lee Cheribini's descendents still builds them at the same yard in N.J. Now all glass ( deck used to be laminated wood).They also built some pretty motorboats. If I had a $1m+ and the bucks to maintaiin one it would be a kick to have one. Small inside but two could live on her.


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## Lou452

chris_gee said:


> Some brief comments on the Contessa 32 since it has come up. Yes in effect the keel is in between, it has a skeg hung rudder and overhangs. It is an excellent sea boat, and sails well. It likes a bit of heel and can throw up a bit of spray which is easily overcome by a couple of strakes or rubbing rail on the bow.
> It is relatively narrow so is less fast downwind than one with the beam carried aft but is more stable. The downside is less internal volume so one sure would not be trying to fit 6 in more like 2 or 3 max on a passage. However that is true for most boats of that length, particularly when you think of storage extra sails etc.
> Being relatively narrow plus having easily accessible handholds makes it safer in a seaway versus being tossed from side to side.
> It might be said to be a bit harder to dock than a fin keel but with a bit of practice it is not difficult.
> A number of factors interact in choosing a boat, money, comfort, crew numbers, prevailing weather, ease of handling, intended use. Personally I rank the security of having a good sea boat highly. Sure it has to sail well but speed for a non-racer is not the dominant factor.


 I Thank you for the insight. Regards, Lou


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## Lou452

Ok Wolf and Paulo I am reading some books that I can understand most of the tech stuff I will not pretend I get it all with the stability charts and the sea motion comfort charts Looks good but I am just the average Joe. One book I just is finished is John Vigor : Twenty Small Saliboats to take you anywhere. Reading now Beth Leonard : Voyagers hand book. Next on my list is Lin Pardy, Larry Pardey : Storm Tactics Handbook 
What seems to be an issue is heaving to and coming back up if capsized. I have found so far the books look to favor full keels narrow beams ? Fin keels do not look after themself or forgive the sailer that is beyond his endurance limit needing sleep food and warmth ? Does a fin keel need more skill and crew to be safe? 
I also took note that most of the boats in said books are boats from the 1960s 70s This thread takes aim at this old vs new but lets review. 
This thread is a class room for me.
I will not be a big name racer. My skill is low level but growing as with a lot of new hands. I do think going up wind is very important. I see myself always short on crew members. I will be in a used boat. Like most sailors I would like a boat that is safe, fast comfortable and has a shallow draft at a low cost. The word here will be a compromize. 
Your thoughts are read more than once so post away my friends. Thanks you, Lou


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## wolfenzee

I don't race, never have never will....I can go very nicely in light air and close to the wind.....but what is important is when the weather gets dicey, I don't find really nasty weather as tireing as with a squirrley light wieght racing (or cruiser/racer that emulates a racer).....don't have to reef as soon (40kt breeze is down right fun).
I grew up on the Chesapeake so don't consider 5' shallow draft....but when I look around a fin keel boats, a couple feet makes a big differance.


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## killarney_sailor

Lou452 said:


> What seems to be an issue is heaving to and coming back up if capsized. I have found so far the books look to favor full keels narrow beams ? Fin keels do not look after themself or forgive the sailer that is beyond his endurance limit needing sleep food and warmth ? Does a fin keel need more skill and crew to be safe?
> Lou


You bring up three separate issues each of which could be discussed at length., 
1. Heaving-to -- it is relatively easy to heave-to with most boats. The tricky bit is heave-to with little or no forereaching. We heave to from time to time but typically fore-reach at 1 to 1.5 knots which moves us out of the slick that you create by sliding to leeward. The whole idea in the Pardeys' book of using a parachute sea anchor at an acute angle to the bow is to stop the forereaching. We have all that gear and even had it rigged on the cabin sole behind the table on the way from Mauritius to South Africa last year but did not even think about using it. BTW, all that gear is not cheap, for our boat probably close to $2500.
2. Capsize recovery -- Everything being equal (and it rarely is) a narrower boat recovers better than a wider boat. Most full keel boats are narrower, often much narrower, than most fin keel boats and hence should recover more quickly. But, if beam is equal, a fin keel with a bulb should recover better since the righting moment is greater (again everything being equal).
3. Comfort - To my mind, comfort has two parts. One is typical heel angle. I sailed on a friend's Alberg 37 and really did not enjoy it since we were so far over on our ear the whole time. I guess you get used to it but it was not for me. Our Bristol basically rarely heels to 20 degrees even when it is honking. The other consideration is how the boat moves in the waves. Heavier boats tend to move in a more controlled way which I find less tiring.

A final boat about comfort and safety. If you can make a passage in 10 days rather than 12 days that means there are two days when you don't have to worry about safety and comfort.


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## PCP

killarney_sailor said:


> ...
> 2. Capsize recovery -- Everything being equal (and it rarely is) a narrower boat recovers better than a wider boat. ..
> .....


Yes, but everything being equal (and it rarely is) a beamier boat is harder to capsize than a a narrower boat.

Regards

Paulo


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## wolfenzee

Slocum's boat SPRAY (a beamy boat).....had a "point of vanishing stability" of only 90degrees.....I have a narrow boat, but according to calculations, the point of vanishing stability is pretty extreme...in the other way.
As far as difficulty in capsizing, a wave can capsize just about anything. What is important is how fast (if at all) the boat will come back up.


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## PCP

wolfenzee said:


> Slocum's boat SPRAY (a beamy boat).....had a "point of vanishing stability" of only 90degrees.....I have a narrow boat, but according to calculations, the point of vanishing stability is pretty extreme...in the other way.
> As far as difficulty in capsizing, a wave can capsize just about anything. What is important is how fast (if at all) the boat will come back up.


Yes, a huge breaking wave can capsize anything but there are a proportionality between beam and the size of a wave needed to capsize a boat. A smaller breaking wave can be enough to capsize a narrow boat but not enough to capsize a beamy boat.

Regarding vanishing stability a beamy boat has not necessarily an AVS worse than a narrow boat. The Avs has nothing to do with beam but with how deep the CG is. Being an old design I don't think your boat will have a very big AVS, I mean it has not a big draft and the weigh is not all on a bulb on the bottom as in a modern boat. There are many modern beamy boats with AVS around 130º but probably that is not more important than the force that they are making to right itself up at 90 0r even 100º. After all it is way more frequent a knock down then a complete roll and at that position the boat is vulnerable: You want it up again as fast as possible. A small wave that hit the boat at that position can capsize the boat.

Regarding what you say it is more important ( *"What is important is how fast -if at all- the boat will come back up"*) I guess that what is more important, providing the boat has an AVS superior to 110º is the proportion between the positive and the negative part of a stability curve. Meaning the proportion that exists between the energy needed to capsize a boat and the energy required to right it up from inverted position. Saying it in another way, the proportion between the size of a wave capable to capsize the boat and the size of a wave capable to re-right the boat again from the inverted position.

Regards

Paulo


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## outbound

Would offer when it gets really nasty best point of sail maybe dead downwind under barepoles with Jordan series drogue or the like deployed off stern with helm fixed amidships,companionway closed and everyone down below. In this set up even extremely deep draft high aspect bulbed fin keeled boat do just fine. Crew is down below either on sole amidships or in quaterberths ( wherever is most comfy). Lying ahull or heaving to are not believed to be as safe by many authors. Have heaved to to have lunch ( can be done on virtual all fin keel boat if a little forereaching allowed) but do not consider it the ultimate storm tactic. Running with series drogue will work for beamy,narrow,full,fin or just about any boat. With sufficient number of drogue cones sufficient sea room for drift is obtained. Current open transom sugar scoops will shed water quicker in the event of being pooped. Agree it is a faulty thinking to presume a good modern boat is any more uncomfortable or unsafe than old boats derived from Norwegian coast guard double enders and the like. Have owned boats built for single handed trans Atlantic races and very traditional boats. When done right both can be safe and comfy in a seaway. Personally, have chosen a moderate beam, by modern standards somewhat heavy bulbed fin keel boat as my "last boat". It's behavior in all settings comforts me. Others make other decisions and they all may be very correct for how they are going to use the vessel.


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## wolfenzee

according to the ratio calculators (which I don't particularly trust) the angle of vanishing stability on my boat is 183degrees (which means 177 degrees on the other side, in other words there is no point where the angle of stability vanishes).... if someone has an accurate calculator and/or can figure the AVS I would be glad to give all the specs of my boat. My boat likes to heel around 30degrees and performs very well at that heel. Because it is better ti find the limits of your boat rather than be shown them, I decided to have some fun...in 15kts of wind with main and 180 genny (800-900sqft combined) I sailed for 3 hours at a 40 degree heel, doing hull speed with cap rail under 3" of water. If a gust of wind were to push the boat over to 45 degrees it would immediately swing up into the wind. The base of my rudder is 5' down....the ideal size of the rudder is said to ne 15% of of the waterline length....as the original rig on my boat had a nasty weather helm the designer chose to make that 25%.


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## mitiempo

wolfenzee said:


> according to the ratio calculators (which I don't particularly trust) the angle of vanishing stability on my boat is 183degrees (which means 177 degrees on the other side, in other words there is no point where the angle of stability vanishes).... if someone has an accurate calculator and/or can figure the AVS I would be glad to give all the specs of my boat. My boat likes to heel around 30degrees and performs very well at that heel. Because it is better ti find the limits of your boat rather than be shown them, I decided to have some fun...in 15kts of wind with main and 180 genny (800-900sqft combined) I sailed for 3 hours at a 40 degree heel, doing hull speed with cap rail under 3" of water. If a gust of wind were to push the boat over to 45 degrees it would immediately swing up into the wind. The base of my rudder is 5' down....the ideal size of the rudder is said to ne 15% of of the waterline length....as the original rig on my boat had a nasty weather helm the designer chose to make that 25%.


I would be curious what numbers you used to come to this conclusion.


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## PCP

The angle of vanishing stability is not a ratio. I don't see how that can be found by a calculator without full measures and all the weights of boat parts. What calculator are you talking about?


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## wolfenzee

According to the US Sailing calculator http://www.sailingcourse.com/keelboat/design_winds.htm my AVS is 193.64

http://www.sailtrain.co.uk/stability/vanishing_stability.htm and http://www.radford-yacht.com/stablty1.html both explain the AVS
According to the RADFORD "Safety of Small Commercial Sailing Vessels Code of practice"(see table below and/or link), the 110 degree AVS that someone stated was typical of fin keels would not even be safe in Catagory 2 (up to 60 miles from a safe haven)









Historically the older style boats had a much higher AVS even though thier narrower beam. Typical sailboats produced from the early 70's on have LPS's (limit of positive stability = AVS) in the 100-120 degree range. "Designs typical of the 30's and 40's (e.g. many Alden designs) have LPS in the 160 degree range. from "http://dan.pfeiffer.net/boat/ratios.htm

The actual formula is: AVS = 110 + ( 400 / (SV-10) )
SV is the screening value and is calculated by:
SV = B2 / (R x T x V1/3)
Expanding SV in the first equation gives:
AVS = 110 + ( 400 / (B2 / (R x T x V1/3))-10) )

B = beam of the hull (no rub rail) in meters
R = ballast ratio
T = hull draft at B/8 from centerline in meters
V = displacement volume in cubed meters

It's not so much as a wide boat being more stable right side up, but upside down....I wide boat is not going to want to right as quickly as a narrow boat.


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## wolfenzee

The calculator called for draft (not including keel) but the formula called for draft at beam/b away from center line. Which when figured in on my boat would make my AVS 167.7degrees....alot more realistic than 193.

calculator used: http://www.sailingcourse.com/keelboat/cal__avs.htm

numbers used were beam: 8.75'
total weight: 15,000lb
draft at hull B/8 from centerline: 2.5'
ballast & keel weight: 4400lb
(4000lb ballast and approx keel wieght 400 figured on 31lb/cf for fir)


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## PCP

wolfenzee said:


> According to the US Sailing calculator Sailboat Design and Stability my AVS is 193.64
> 
> The actual formula is: AVS = 110 + ( 400 / (SV-10) )
> SV is the screening value and is calculated by:
> SV = B2 / (R x T x V1/3)
> Expanding SV in the first equation gives:
> AVS = 110 + ( 400 / (B2 / (R x T x V1/3))-10) )
> 
> B = beam of the hull (no rub rail) in meters
> R = ballast ratio
> T = hull draft at B/8 from centerline in meters
> V = displacement volume in cubed meters


That is what I thought. That formula, at best, works for a certain kind of boat typical of the 80's (Fin boats with non bulbed keels) and even so gives errors superior to 15º. It gives not meaningful results to old boats like yours or modern boats with deep draft and a bulb.

As I have said one of the most important factors regarding the determination of AVS is the position of the CG. That formula in what regards that has only into account the B/D. it is evident that regarding boats with the same weight a boat with 40% of B/D, distributed uniformly by a a long keel with 1.4m provides a lot less righting moment than 25% of B/D ratio in a bulb at 3.0m (for instance on a cruising Pogo 12.50). Regarding that formula the Pogo is regarded as a boat with a much higher CG when it is the opposite and by far.

For finding the AVS it is needed to find the center of buoyancy, the center of gravity and the meta-center. You can only do this with careful calculations regarding the shape of the hull and the weight of all boat. I don't mean the displacement but the weigh of all parts of the boat, including ballast and their relative position.

You can do that also with inclining experiences to determine RM an adequate computer program That is made all the time in what regards serious racing by specialists, to be able to rate the boats in ORCI.

Simplistic formulas like that one or the capsizing ratio does not deserve any credibility, specially in what regards very old or modern boats.



wolfenzee said:


> ...the 110 degree AVS that someone stated was typical of fin keels...


It seems to me you are mistaken. I don't remember anyone stating that. I would have noticed because that it is not true.



wolfenzee said:


> It's not so much as a wide boat being more stable right side up, but upside down....I wide boat is not going to want to right as quickly as a narrow boat.


Sure, it is needed more force to re-right a beamy boat than a narrow one and the opposite is also true, it is needed more force to capsize a beamy boat than a narrow one.

A perfect example of a shape with a 180º AVS is a cylinder, a tree trunk for example. Very easy to "re-right" and very easy to roll. nobody wants a boat like that. what is more important, providing the AVS is enough to right the boat easily from 90º, is the proportion between the energy needed to capsize it and to re-right it. If the energy to capsize the boat is 4 times bigger than the energy to re-right it, it means that if a boat can be capsized by a 3m breaking wave, it only need the energy of a wave with 0.75m to be re-righted.

A sea condition capable of forming 3 m breaking waves will have plenty of 0.75m waves that will put it back on its feet very quickly.

Now imagine a boat with 180º AVS but that needs only a 1.5m breaking wave to capsize it. A situation with 2.0m breaking waves would capsize that boat easely while the other one would have not any problem. Sure, it will come up again...without a mast and with an interior in complete disarray.

Do you really think an easier boat to capsize is better, just because it has a bigger AVS?

Of course we are only looking at it in what regards static stability. In what regards dynamic stability a really beamy boat with a small submersed area (including the keel area) will have advantages, being able to convert more wave energy in a kinetic movement instead of a rolling movement. The best example of this situation are multihulls. Centerboarders and boats with narrow keels come next.



wolfenzee said:


> According to the RADFORD "Safety of Small Commercial Sailing Vessels Code of practice"(see table below and/or link), the 110 degree AVS that someone stated was typical of fin keels would not even be safe in Catagory 2 (up to 60 miles from a safe haven)


Safety of Small Commercial Sailing Vessels Code of practice is not a Radford document but one that was made by the wolfson unit to the British government more than 20 years ago.

Here you have the actual full document that don't use that table but makes the AVS demands increase with size:

"Safety of Small Commercial Sailing Vessels Code of practice":

http://www.dft.gov.uk/mca/blue.pdf

That regards commercial sailing vessels, not private boats and that's a huge difference.

Basically what they don't want is small sailingboats being used as training boats in offshore situations. If we consider a 50ft boat the AVS requirements are of about 122º. That is not far from the average. Many modern mass production boats have more than that.

Anyway, as all the rules it has flaws and on this case one of them is using only AVS to access boat stability. In that regards the RCD, that is a more recent document and has been upgraded more times, is much more effective, I mean in the ways the stability is evaluated: They use not only AVS but much more data taken from stability curves, including max load and min load curves.

Regarding a sailboat not being safe offshore with an AVS of arouind 110º and *"would not even be safe in..up to 60 miles from a safe haven"*, may I remind you that a Sabre 402 has only 114 and that an OVNI 43 had about 110º? The OVNI 43 was the boat chosen (after having many other boats and several circumnavigations) by Jimmy Cornell for his circumnavigations and extreme navigation in high latitudes and one that he recommends to everybody.

Again, as I have said, the AVS is important but providing it is enough to right the boat easily from a knock down, there are many other important factors in what regards stability and seaworthiness to consider.

Even if I would prefer that the OVNI or the Sabre had an AVS around 120º I would fell safer going offshore on one of those boats than on your's. Not that I would have any problem in going offshore in your boat, but I would feel more secure in any of the other two: They have a superior safety margin.

I Understand your love for old boats (that I share too) but I find a bit odd that you keep thinking that XIX century designed boats are safer than modern designed sailboats.

Regards

Paulo


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## wolfenzee

AVS refers to a boats righting ability.....there is another, sometimes called a "capsize screening ratio" which addresses how easily a boat capsizes, a good AVS doesn't mean a bad capsize ratio SloopIT - Boat performance calculator. The capsize ratio of my boat is 1.42....which is considered to be very good (2 or higher is not considered safe at sea).

William Atkin was famous for designing safe ocean cruising boats, the design of mine was commissioned with the intent of using it for ocean cruising. Of the 40-50,000nm (alot of which were ocean miles) the only comment regarding it's performance at sea was "It's a good sea boat" (from the owner that had here for 15 years and sailed everywhere from Mexico to Alaska on my boat and all over the world on others). I would take my boat to sea ahead of 95% of the boats in the harbor, I truly feel safe in my boat.


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## wolfenzee

Modern day sailboats try and emulate racing boats while being as spacious and/or comfortable as possible in their accommodations...while at the same time keeping production costs down. Speed is the main performance consideration....safety in "blue water conditions" is not factored into design as much as being byproduct of design. Boats of the sort I have were designed specifically with ocean cruising in mind, not trying to behave and/or look like a racer, not trying to be comfortable for the weekend sailor, not designed around what the marketing industry is trying to make popular.
My boat was designed around work boats of the time (lines are similar to a Gloucester fishing schooner). Just because a boat is of a modern day design doesn't automatically make it better, just because elements of rig are no longer used, doesn't make them inferior. I am not talking down modern boats just because they are new, but rather defending mine (there is nothing wrong with it just because it is old)....My boat was designed 75 years ago by one of the leading designers of ocean cruising yachts of the time (his designs are used in new "blue water boats" to this day), it was commissioned specifically as a single handed ocean cruiser with more of an emphasis of performance than accommodations (boats built for the American market seem to try and squeeze as many bunks in them as possible)


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## outbound

Wolf your boat is a magnificant design. No one in their right mind would say otherwise. Both a gas operated semi auto 30.06 and a muzzleloader bring down deer. To an collector/hunter both have appeal. The deer is just as dead so he feels the same about both as well. Still, the physics of the ocean and weather remain the same and folks will always strive to find a better solution to deal with it. You are right as regards many production boats but realize they are aimed at a different segment of the boating public then your boat is and was when it was constructed. Compare apples to apples and for the same segment you refer to there are boats still being made which incorporate the genius of subsequent generations. Some are the equal to your vessel and the audience who buys them probably know what a gem you own.


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## outbound

Pease note my boat was designed to cross oceans, interior set up for 2 to comfortably live aboard ( will sleep 7 with no hot bunking) and one to sail. Same for the same size Morris', HR s etc. Yes a lot of creature comforts and some improvement in the expected days work have been added. Isn't that to the good. I hope I or who ever sails my boat in 75y from now to be able to feel about it the way you feel about yours. Now that's a successful design.


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## wolfenzee

outbound said:


> Wolf your boat is a magnificant design. No one in their right mind would say otherwise. Both a gas operated semi auto 30.06 and a muzzleloader bring down deer. To an collector/hunter both have appeal. The deer is just as dead so he feels the same about both as well. Still, the physics of the ocean and weather remain the same and folks will always strive to find a better solution to deal with it. You are right as regards many production boats but realize they are aimed at a different segment of the boating public then your boat is and was when it was constructed. Compare apples to apples and for the same segment you refer to there are boats still being made which incorporate the genius of subsequent generations. Some are the equal to your vessel and the audience who buys them probably know what a gem you own.


There are alot of boats in this town that are "historically correct" andor are fine examples of an older style of boat.(down to dead eyes and kerosene running lights)but other than looking pretty for the "wooden boat snobs" (the sort of people that would keep a classic car in a garage under a dust cover and only take it out on sunny days) they suck on just about everything across the board. My boat isn't just a "quaint old boat", the designer, builder and every one of it's owners has made improvements for the purpose of functionality and/or performance with out trying to be "historically correct"....in an e-mail to Pat Atkin about what was done, she responded "Oh, you have a "modified Atkin". Even though it might not be as William Atkin had designed it, he would have approved of the alterations.

The Sharps rifles were made in the mid to late 1800s and were known for long distance accuracy.
The rifles used by the Imperial Russian Army (late 1800s)were also known for accuracy.

Not sure exactly what you would compare mine to (am not up on antique rifles) something that is a bit on the heavy side, but solidly constructed and good performer. Some boats may fall under the category of a blunderbuss...both old and new (like the Island Packet)


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## outbound

go black power hunting on occassion. Materials used /designs are varied.
Can pick up modern black power gun using synthetic stock, power pre formed in measured cyclinders, pre formed 50cal sabots. - get my deer. Good gun, easy to use, easy to aim,well designed and accuate.
Close friend let me have use of true Tenn. long rifle. ( ancient thing but well kept) Beautifully made but heavy to carry and a little more effort to charge and mantain.. Still good rifle- well designed, easy to aim, and accurate- get my deer.
Which is better?- Not a germaine question. Totally depends on what criteria the answerer brings to his response.
Are there features of the "modern" black power gun that represent advances- Yes.
Is the hex barrel "old" gun a thing of beauty,durability and marvel of function- Yes
Do both work- yes

Are there modern black power weapons that are junk- yes
Are there "old" guns that are junk- yes

Agree merit has nothing to do with age. But intelligent people have looked and thought about our tools- be they boats, guns, cars, or hammers. Not to acknowledge advances is cut yourself off from another source of wonder and enjoyment. Paulo has a running thread which I read often with great enjoyment. But those boats don't meet my needs or aesethesics. I think some of current advances would actually decrease my enjoyment of my boat. However, There have clearly been advances in our undestanding of fluid dynamics, cad/cam programs and computer design have aided our N.A.s . Still think trick is to incorporate current knowledge tempered by real world experience. I went with a 13 y.o. design. I talked with multiple owners back to hull 2 ( I'm hull 50). Boat is "modern". Each one has new "features" as technology advances. Boat is "proven" and not cutting edge. I think boat filled the nitch that Valiant once did. I looked at many V50's before I blew the money on this one. Does that mean the sun shines less strong and wind less on the V50- no. Does that mean the V50 is not something I woul sail accross the pond and think is a great design I would be very proud to own-no. Does that mean the O46 doesn't have many advances incorperated in it's design and execution compared to a V50- no.


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## PCP

outbound said:


> ...
> Agree merit has nothing to do with age. But intelligent people have looked and thought about our tools- be they boats, guns, cars, or hammers. Not to acknowledge advances is cut yourself off from another source of wonder and enjoyment.
> 
> Paulo has a running thread which I read often with great enjoyment. But those boats don't meet my needs or aesethesics. I think some of current advances would actually decrease my enjoyment of my boat. However, There have clearly been advances in our undestanding of fluid dynamics, cad/cam programs and computer design have aided our N.A.s . Still think trick is to incorporate current knowledge tempered by real world experience. ....


I don't understand your point. In my thread I cover all sort of boats, including bluewater and voyage boats. Yes they are modern and represent the best there is on the market and that means the best sailboats available ever, depending for what they are designed for.

Regarding experience, most of the designers of the new generation (well, they are not young anymore) were simultaneously sailors and I don't mean occasional sailors but circumnavigation and solo navigators that made transats, most of the time with boats designed by them. After that they kept sailing but most of all build many boast for others that were doing the same, accumulating experience all the time. Boats like the OVNI are being built over a previous circumnavigation experience and being improved for the last 30 years based in the experience fruit of countless circumnavigations (I know a guy that had done 3 on the same boat) and brought back by clients: Is this not experience enough?

Most shipyards in Europe have produced hundreds, some many thousands of boats, always learning with previous experience, always improving based on solid acquired knowledge: this is not experience enough?

I really don't understand what you mean. The edge technologies you talk about are only edge from a point of view 15 years old. Nobody uses new unproved technologies on cruising boats, they are tested first for many years in racing boats that circumnavigate and cross oceans with a solo sailors in conditions and during a period of time that surpass the live and demands of any cruising boat. Only then are they used on cruising boats and are used because they are better and more efficient materials, extensively tested.

The fact that the designers that use those materials on race boats are the same that years later, if they prove to be a better option, design cruising boats gives an added security in what regards safety from the design point of view: They know exactly what they are doing and are not using cruising boats has a testing ground. Just making better cruising boats based in experience acquired in racing boats with better materials and a more efficient design.

Regards

Paulo


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## wolfenzee

When I replaced my rigging last spring I asked the local rigging shop for advice and was told. "Hold on a sec....I think within this little box...you are outside this box....I'm sorry I can't help you". I have a fine rig, very efficient, just different....my point being that just because any aspect of a boat doesn't fall with in the tight little "box" that is modern day yachts.....doesn't mean it isn't a good boat. Alot of really kewl stuff has been replaced for the sake of something new....new does not necessarily mean better.

If I were ro get a fin keel I would get a Scanmar 40.....though there were only 20 built about 15 years ago. I worked for the US importer (gave me a chance to get to know the boat and boats from that manufacturer intimately) and at the time they went for $130K....if can find one now they would be located in Europe and cost about £70,000 ($110,000).....A really nice boat though.








Specs: http://www.yachtworld.com/core/listing/boatMergedDetails.jsp?boat_id=2355227&ybw=&units=Feet&currency=USD&access=Public&listing_id=42024&url=

If I had the money I would have a boat built with the same lines as mine but 40-50%bigger, rigged as a schooner w/aft cabin, also strip planked.


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## outbound

Paulo- I'm not disagreeing .Think you are picking a fight where no fight exists. Once I decided I wanted a new boat and was willing/able to pay for it short list was a one off making use of many very recent construction and design parameters, the Boreal which some would think is a fast and possibly more forgiving evolution of the ONVI and the Outbound. Think Carl and Phil (had)have considerable real world experience.Still, as you look at boats old or new - you need to decide what makes sense for you. I wanted internal ballast, bulbed fin keel, solid glass hull, excellent turn of speed with safety and comfort in all conditions that would work for 2 as liveaboards. Dragged my wife through countless boatyards,spoke with countless owners and yard workers and saw many boat shows over the course of years.Have 35 years messing with boats. Looked at NA portfolios. Read multiple books about "favorable and unfavorable" features. Tried to educated myself about available contruction materials and techniques Did the due diligence to extent possible. Did research on service life, cost and availability of repair, + efficacy of repair. Decided what I wanted from the old and new. The Outbound will be my boat until I die lord willing. I'm not a European with the resources to buy a new boat every few years. To the extent possible knowing this was going to happen once wanted the comfort of other peoples experiences. I don't buy cars in their first model year either. Want others to work out the bugs. My boat's internior bears some basic resemblance to earlier versions but is quite different. Many coponents are different as Phil dligently learns from what hasn't worked in this design and what new changes will make this vessel the best it can be. You don't get that same evolutionary change with new molds and tooling. You may disagree with my decision or the Wolf's but to assume these decisions are not driven by intelligence and made on the basis of fanciful notions or resistance to change is absurd. PSC has just produced a multimillion buck Ketch with a single rudder-?Is that client unaware of what's out there for design or has he chosen those features old and new which make sense for him. Covey Island still makes makes excellent boats using modern wood construction but Gannon and Benjaman's boats are still coveted. Why do you have trouble understanding I learn from your thread and appreciate the advances but reserve the right to pick and choose what I think makes sense for me. I have a friend who likes Morris. Again old and new features. Some wish for a Shannon- new design but old school strength in no nonsense construction. The PSC, Morris, Shannon, new HR aft cockpits , Outbounds 46/52 are boats being built now. None are twin rudders/ hard chine boats.I understand the logic but it's not for me. To assume the CLIENTS ( not the N.As) don't have real world experience of their limitations ( time, money,physical health, use etc.) and don't know what they want is offensive. I do think that some of the boats on your thread are great boats. But I don't know which ones they are. I do believe I have a great boat.


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## PCP

outbound said:


> Paulo- I'm not disagreeing .Think you are picking a fight where no fight exists. ...
> 
> I don't buy cars in their first model year either. Want others to work out the bugs. ....
> 
> You may disagree with my decision or the Wolf's but to assume these decisions are not driven by intelligence and made on the basis of fanciful notions or resistance to change is absurd. ...
> 
> Why do you have trouble understanding I learn from your thread and appreciate the advances but reserve the right to pick and choose what I think makes sense for me. ...
> 
> ..To assume the CLIENTS ( not the N.As) don't have real world experience of their limitations ( time, money,physical health, use etc.) and don't know what they want is offensive. I do think that some of the boats on your thread are great boats. But I don't know which ones they are. I do believe I have a great boat.


I am not picking a fight with nobody, Wolf's boat is great if we consider the pleasure of owning a classical or traditional boat, in what regards to maintain alive a tradition and all that kind of stuff. I really appreciate that (i even like that) but thinking that in what regards form/function and the ability to perform a given task, in this case coastal cruising with some offshore cruising, a XIX century design is better or close to what can offer a XXI century sailboat designed to perform the same tasks, makes no sense and It is only in what regards that that I don't agree with Wolfe. His boat is beautiful and a great design, it is not his boat that is in question but his thought that all modern boats, even the ones designed for a similar function are functionally worse then their boat, not by a subjective pleasure satisfaction (of owning a museum piece) but in real objective parameters like seaworthiness, speed and interior comfort and space.

Regarding you it is about the same thing, not regarding a centuries old design, but regarding a 15 year's old design regarding new designs:



outbound said:


> Paulo has a running thread which I read often with great enjoyment. But those boats don't meet my needs ... Still think trick is to incorporate current knowledge tempered by real world experience. ....


and the thought that a 15 year old design can be better than all boats the market was now to offer. I don't mean subjectively (about aesthetics or irrational dislikes) but objectivity in what regards form /function. Whatever the use you do to your boat I am quite sure the market has to offer better simply because 12 or 13 years is a huge time in what regards boat development and design. I don't mean about money or value (regarding a used boat) that is not what is at stake here, just pure performance in the several items.

With cars it is the same. It makes no sense to say that a same type of car was better 12 years ago than it is now. You say you don't buy new cars for having time for the bugs to be found out. I never had a problem with that regarding cars but I can respect that, but then we are talking about you buying the same model with one or two years, not an older model with 12 years. The new model has already suffered probably 3 big stage improvements over the older model and will out perform it in many ways.

I consider the Outbound a great boat. That is not what is in question but you saying that today market has nothing better to offer (for the satisfying the same functions) regarding an almost 15 year's old design.

Regarding NA to be divorced from the client's experience that does not make sense. Clients like you or any other client knows what they want (even if they have different needs and want different types of boats). If a NA does not offer what they want the Shipyards that uses his designs will go Bankrupt.

On the very competitive European market they have to be very attentive to the client needs and fulfill them. Another thing is to consider that a client know more about technology and design than them and the right way to offer the best solution to a given need. In what regards that the Europeans are more humble and don't question the superior knowledge of the Nas, that is based on solid science, technical knowledge of the different materials, extensive experience and the feedback brought back by hundreds, or thousands of boat owners.

Regards

Paulo


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## outbound

Paulo with all due respect I guess we will just have to agree to disagree. Our perspectives are different. What I'm saying is there are boats being designed now with basically the same parameters as my boat that do not incorporate the features you skillfully demonstrate concerning canue shape, chines, torpedo bulbs with bulb in part in front of fin etc.Construction techniques and materials are different. But at the end of the day what the owner is able to do, how he/she is going to use the boat and in what environment the boat is used impact on what boat he wants to build. For me a triple track boat increases the odds I'm going to pick up lobster pots or need a diver, solid glass means I can get an excellent repair ( god forbid) most anywhere, weight means more comfort to me and less sensitivity to loading, resale value is secure etc. All I'm saying is what's best for me even in your rational world may not be the "best" by your parameters and I'm writing the check. In your an ideal world you would have the resources to replace your boat annually and make use of all advances. In my world I will pick and choose what advances I want to make use of in view of what makes sense for me. I am not saying they are not advances but do expect Phil to use these molds for years to come as this boat makes sense to me and many others.


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## wolfenzee

I never said "all boats....".actually the opposite, I have continued to point out how people generalize too much. There are those who have "museum piece" boats, which they keep "historically correct" (or at least their interpretation), kept shiny and pretty (and run for cover when anything over 10kts kicks up)....they take them to boat shows sailing on sunny days. My boat was designed 75 years ago, but is not a "museum piece"...the building process included techniques that didn't exist when it was designed (which were improved on later on). The boat was designed as carvel plank, but was built as strip plank, glued and covered with fiberglass (later replaced with fiberglass using epoxy resin), there was alot of lamination and fiberglass work in the construction....not "historically correct". AS well as rig tweaks that differ from the designer's original plan.

As far as the age of the boat.....in SAILNET polls "What age is your boat" 82%+are over 20years old while 4% are 1-4years old. There is no reason to buy a factory new boat.....for the cost you can find something far better and have money left over (A used SWAN costs less than a new Catalina ). Buying a new boat just because you can afford one is a waste of money. Of course what keeps the marine industry alive is people who have more money than they have time and/or sense...people who should spend more of thier time sailing.


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## PCP

outbound said:


> Paulo with all due respect I guess we will just have to agree to disagree....


Not a problem with that, The world would have no fun if everybody thought the same way

Regards

Paulo


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## wolfenzee

A boat is a very individual and personal reflection of who someone is...everything in life is a compromise, it's just more obvious in boats. Back to the thread, fin keels and full keels both have there advantages and there is a boat out there that best reflects your needs, wants and desires. I was able to find a boat that best reflected my personality and sailing plans..blue water capability, grace and performance...my main compromise was space (she is a tight little ship)


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## Classic30

wolfenzee said:


> I never said "all boats....".actually the opposite, I have continued to point out how people generalize too much. There are those who have "museum piece" boats, which they keep "historically correct" (or at least their interpretation), kept shiny and pretty (and run for cover when anything over 10kts kicks up)....they take them to boat shows sailing on sunny days. My boat was designed 75 years ago, but is not a "museum piece"...the building process included techniques that didn't exist when it was designed (which were improved on later on). The boat was designed as carvel plank, but was built as strip plank, glued and covered with fiberglass (later replaced with fiberglass using epoxy resin), there was alot of lamination and fiberglass work in the construction....not "historically correct". AS well as rig tweaks that differ from the designer's original plan.


I guess most people don't realise technology goes both ways:

Most visitors do not notice, but of the large list, a few inventions "historically correct museum piece" boats have benefited from include:
* Plastic ropes (looks like hemp but isn't - but lasts 100 times longer in the sun)
* "Canvas look" terylene sails (lasts longer than Egyptian Cotton): A tiny aside here is that I know of only two Tall Ships world-wide using traditional sailcloth and neither of those travel the world.. Go ahead, prove me wrong 
* Dyneema rigging (looks like gal wire but is heaps stronger, lighter and easier to maintain)
* Modern paints, glues and varnishes..

..and there are 'old' things once forgotten being rediscovered by the new breed of yacht designers - including square-cut mainsails, bowsprits, plumb bows and the importance of hull balance..


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## fallard

There has been more heat than light in the back and forth on this post, but it's still an interesting discussion. I particularly liked that discussion about solid glass vs. cored construction, like solid glass in inherently superior. 

I wonder how Boston Whaler ever made it! There have been numerous cases of a "stress skin" hull being properly repaired. I guess if you are going to end up on the rocks you may want to last a few more minutes before you break up? 

Most of my boats have had solid glass hulls, but my bigger (35') boat has a balsa-cored hull and has made it for 23 years without a problem. The stiffness of the hull is appreciated--no "oil-canning"--and the resultant weight savings make for part of the reason that the boat has a lively response. I''ve been in some really nasty stuff without a worry that the boat would suffer structurally. 

That said, to each his own! If someone wants to buy a new boat, more power to them. That means there may be a bargain for me in the future (if it's a quality boat).


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## wolfenzee

"Technically" I guess my boat would be composite construction (strip plank glued and covered w/fiberglass using epoxy resin), even though the strip plank was solid enough with out the glass. Strip plank/fiberglass is a nice combination if done as part of the building process. Wood that is glassed over after the fact is inviting disaster. The use of laminates in all the spars made for stronger spars. The only "old fashion" materiel I use is bronze, but that is because of advantages iit has I will not go into.


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## PCP

Hartley18 said:


> I guess most people don't realise technology goes both ways:
> 
> Most visitors do not notice, but of the large list, a few inventions "historically correct museum piece" boats have benefited from include:
> * Plastic ropes (looks like hemp but isn't - but lasts 100 times longer in the sun)
> * "Canvas look" terylene sails (lasts longer than Egyptian Cotton): A tiny aside here is that I know of only two Tall Ships world-wide using traditional sailcloth and neither of those travel the world.. Go ahead, prove me wrong
> * Dyneema rigging (looks like gal wire but is heaps stronger, lighter and easier to maintain)
> * Modern paints, glues and varnishes..
> 
> ....


Have a Ford T built in Carbon with am aluminium engine and titanium suspension and it will still be a Ford T. A better one for sure but nothing to do with a modern design, even if those are more modestly built in what regards materials.



fallard said:


> .. I particularly liked that discussion about solid glass vs. cored construction, like solid glass in inherently superior.
> 
> I wonder how Boston Whaler ever made it! There have been numerous cases of a "stress skin" hull being properly repaired. I guess if you are going to end up on the rocks you may want to last a few more minutes before you break up?
> 
> Most of my boats have had solid glass hulls, but my bigger (35') boat has a balsa-cored hull and has made it for 23 years without a problem. The stiffness of the hull is appreciated--no "oil-canning"--and the resultant weight savings make for part of the reason that the boat has a lively response. I''ve been in some really nasty stuff without a worry that the boat would suffer structurally.


Going on with the car analogy: Cars from the 60't 70's amd 80's were much more solid built and heavier. Hit another car without too much speed, or any other thing and you will get probably only a bit of bent tin. Modern cars are incredibly lighter, stiffer by design, waste a lot less fuel and are much faster...but hit another car or a tree and even if it is not at a great speed the car is toast or it will be in need of a big reparation.

Cars and boats are not made to hit things and the advantages of the lighter and stiffer boats will be much more than the ones regarding a slightly superior impact resistance...and even about that I am not sure...I would say that the non cored ones are definitively easy to repair and need less care in what regards making modifications (put screws in it) and that's the main advantage.

The advantages of cored boats are so many that today even conservative builders like HR use cored boats. The vast majority of new non cored boats are like that for price reasons and nothing else.

If you plan to sail in uncharted waters where hitting objects is a big concern than the Aluminium is the material to go and not a non cored fiberglass boat that offer at best only a slight impact resistance but are less stiff and a lot heavier.

Regards

Paulo


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## outbound

Prior Outbounds have had balsa cored decks. Have had bad experiences with balsa in past. Asked decks be divynicell cored. - Done. Pleasure of having a semi custom built the way you want it.


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## hannah2

Just read "full or Fin Keel" from end to start. A lot of interesting posts and many of them are great for the debate. I see both sides on fin and full having owned both. I can't wait to talk about the bad things along with the good things of the new boat and I will in time. I think this debate would be far better if everyone talked about what they have found not so good in their boats design. Lets everyone take to the couch and and tell your story to the shrinks about the design problems you see in your boat.

Our last boat a Mason 44, a cut away full keel boat sailed all over the world which made one circumnavigation, two Atlantic crossings and one trip through the pacific.. 

Things I didn't like about her. Went to weather lousy, would stall at times even when not pointed high going to weather. Why? Just not enough water line and she would hobby horse often when the wrong series of waves went under her. I'm talking 2 to 3 meter waves at lets say at 6 seconds and 60 degree point of sail. It was hard to make head way and easier to heave to or run. But in some situations you have to try and sail into a front. Running the engine under sail helped but did not solve the problem entirely. CCA boats just do not have enough waterline. Still a great offshore boat.

Cheers


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## outbound

Still disappointed you can't get a boat like a cheribini for under a MILLION bucks. Understand narrow - less room inside
Internal ballasted sheel keel- more engineering and expense.

But high aspect fin- have to deal with draft restrictions
Full or cut away- don't point as well, more wetted surface ( parasitic drag) downwind
centerboard- more complexity, harder to get adequate righting arm.
Never owned a centerboard but have all of the rest.
Wonder if a cheribini like boat of 36-40' without the extensive wood work and detail would sell enough to make a production run cost effective in today's market.


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## wolfenzee

What bugs me is people think full keels, ALL full keels automatically don't point very well. My boat with main and working jib gets 35degrees off the wind...but closer as a cutter rig. This isn't pinching it, but moving along comfortably. My boat is a high aspect w/a large fore triangle (J measurement=47% length of the boat) either or both of those would make for good pointing ability.
My keel isn't a "cut away" but isn't a "long full keel".......the deepest point of my keel is the base of the rudder post (maybe that great big huge rudder is why my boat isn't hard to get across the wind, another thin attributed to ALL full keels)


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## hannah2

Didn't know there was any boat that will sail to weather at 35 degrees in open ocean where there is 2 meter or better slop. Even the Mason 44 could sail to 35 degrees in front of Port Townsend or the Hood Canal, but never under ocean conditions, there sure is a big difference. Now that we know there is one boat out there that can sail at 35 degrees in open ocean does anyone else know of more?

We sailed our Mason in a conservative manner even in a following sea. But if we had left too much sail up I know that a full cutaway would have wanted to round up when sailing down an ocean swell. Out of the boats we know of that have been knocked down it was because the skipper had too much sail up and the design of the boat could not handle it and therefor rounded up. 

I'm looking forward in the new boat to see how she handles more sail with the centerboard up and the leeward dagger board down in a following sea and a broad reach. So far the reports are good but until I've done it myself it is just hear say.


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## outbound

Hannah- sounds like you have a great boat. Was back and forth between the Boreal and Outbound. Talked it through repetitively with the admiral + hope we made a good decision and hope you did too. Looking at blogs of owners of both boats ( I'm not to good reading english let alone french) seems we will both be OK. Agree with you the spread sheets don't matter -it's what's your noon to noon and how you feel doing it. How is your galley arranged?
On some full keel boats I have had,especially the double enders, didn't like the way they would squat when running and long bowsprits make picking up mooring more difficult as you need a bridle.


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## wolfenzee

To get to know my boat better I put up too much sail to see what I could learn........firstly it takes alot to get the boat over to 40 (from it's preferred 30 degrees) and keep it there......it would round up when it got over to 45 degree.
Because of the weight of my boat it isn't affected as much by 2'chop as would a light weight fin keel (someone mentioned the "pounding" fin keels were known for earlier in this thread). There is alot of flare at the bow with the original intention of keeping the cockpit dry, the extra buoyancy there would case problems if the boat did not have a decent amount of chain in the chain locker (some lighter boats are designed with the intention of rode/chain combinations)....I have heard it refereed to as "saucy". Going into 15' waves at about 4kts under power, the cockpit remained relatively.


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## wolfenzee

If I were to go with a "production boat" that fit my personal style I would probably pick a Han Christian, for a fin keel I have already mentioned I would choose the Scanmar 40


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## outbound

Think pounding is more a reflection of the entry of the boat throught the water and it's dynamics. Both the Boreal and the Outbound make every effort in design to have favorable gyradius ( weight in center of boat). Both have fine entries. Neither will pound. Appendages are very different. Similarly Cheribinis due to extremely fine entry and narrow hull were known to not pound. Boreal is light,somewhat Outbound heavier, Cheribini much heavier. Due to design all will be very comfortable boats. Agree Outbound in part makes use of it's weight to improve ride but that it not the major determinant in my understanding.
Weight in a cruising boat is an interesting thing. You spend huge money getting rid of weight. Then put heavy fuel, water,stores,anchor chain in it. Did a Bermuda on a tri. Captain/owner was concerned about the weight we had in our bags as we carried our kit aboard. He was absolutely right in the setting of a race.


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## PCP

hannah2 said:


> Didn't know there was any boat that will sail to weather at 35 degrees in open ocean where there is 2 meter or better slop. Even the Mason 44 could sail to 35 degrees in front of Port Townsend or the Hood Canal, but never under ocean conditions, there sure is a big difference. Now that we know there is one boat out there that can sail at 35 degrees in open ocean does anyone else know of more?
> ...


 A modern performance cruiser, if it is specially good going upwind can do that providing it has enough wind. Last year I had a very enjoyable sail between Islands making 6.5K against 1.5/2.0 m short period waves with 18K apparent wind pointing at 27/28º. In the Atlantic, even with bigger waves, but with normal ocean waves (and not those nasty ones you have in the Med) I would be pointing probably the same but doing 7/7.5K.

Hannah, sailing a modern performance cruiser has its advantages...as well as its disadvantages. Pointing and speed are the advantages. A more limited carrying load capacity a smaller tankage and a bigger draft the disadvantages.

Regards

Paulo


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## hannah2

outbound said:


> Hannah- sounds like you have a great boat. Was back and forth between the Boreal and Outbound. Talked it through repetitively with the admiral + hope we made a good decision and hope you did too. Looking at blogs of owners of both boats ( I'm not to good reading english let alone french) seems we will both be OK. Agree with you the spread sheets don't matter -it's what's your noon to noon and how you feel doing it. How is your galley arranged?
> On some full keel boats I have had,especially the double enders, didn't like the way they would squat when running and long bowsprits make picking up mooring more difficult as you need a bridle.


Outbound, Glad to hear you found the boat you and the admiral really want to sail. It is so important that the both of you are happy with the purchase. We spend a lot of money on our dreams and to know you made a purchase that both can live with even though there can be some things that are not perfect when you get to know that boat. But the selection is a moment of satisfaction for both crew members. You have a beautiful boat and one we would have considered if we had not had such a desire for the aluminum center boarder.

We decided on our new boat choice for many reasons. Both being 60 we wanted to have a new experience in our years of sailing, sort of feeling new energy in what we love to do. This will be our last purchase of a serious boat. We think we made the right choice for us but until I sail her seriously I won't know if it will fit us as we envision. Good thing is if we are uncomfortable with her I already have buyers for her at more than we payed for her, few boats are that way but the small market for a boat like ours is very strong. There are sailors out there who want to do things far more adventurous than we do who want a boat such as the Boreal. But we are excited about sailing a modern designed boat such as ours, we are experienced sailors of long distant cruising and look forward to the benefits that boats like our offer. We were convinced of this after our last cruise through the S. Pacific and seeing all the French aluminum centerboards going every where one can imagine and always happy with their product.

I noticed you mentioned that you thought the centerboard boat may be a bit more difficult to sail, I think that is what you were saying. I thought the same also at first but after sailing the companies boat and talking first hand with other Boreal owners who are going everywhere I think it is an easy boat to sail in all conditions. Guess we will be finding out soon. We are looking forward to doing a hard month or so of sea trials and enjoying the learning process of a different designed boat than what we have always sailed. A big part of our next adventure is the boat itself.

Oh, on the galley. We know it is not what we are used too. We have always cooked well on passage and will change our ways to the European style of cooking good meals before passage and putting them away for rough weather. Boreal has bent over backwards in making a more secure galley for us and we appreciate the effort.

Good luck with the new boat, enjoy the adventure.


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## blt2ski

Hmmmmm, so if building an old boat out of newer space age materials is still making it an old boat design......Why the hell are folks building the old "J-Boat" from the early 1900 America's cup boats?!?!?!?!? Or has the rules of the J-class boats changed such that they can? I thought the basic design, specs etc were kept the same, but hulls made of aluminum, carbon spars, laminate sails etc, but still needing to come in using the original design specs of that class. 

I did see a full'ish keel boat today, boy was that a deep sucker! 6-7' on a mid 30' boat. Meanwhile a bit earlier a DuFour 34(e) was put in the water that has a blinking shoal keel! Shallower than my 28' boat. Has a blinken gift rating to boot! I can still beat it boat for boat, when it should be a good minute a mile faster than me! But that is another story.

Marty


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## Oregonian

Paulo,
You claim to have sailed at 6.5k in apparent winds of 18k @ 28degrees. That equals an angle of about 43 degrees and 13k of True wind. 
CONGRATULATIONS: That is the same as an 80 year old Full keel, heavy displacement, 36' William Atkin design. 
What did you say your boat was?


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## outbound

Hannah2- You folks are much more experienced than my wife and I. Life should always be a learning curve. I don't know if ultimately the Boreal would be more difficult to sail. We felt at this time it might be too big a mouthful to easily swallow whereas the Outbound is a fast, very comfortable boat with less variables to deal with. It's speed,size, equipment, design puts it at the edge of our comfort zone as regards ? too much to handle. It's the largest boat I will ever own and first I would have no concerns about sailing "around the clock". Similar to the Boreal there is a small active market for them. Very few are listed as they are sold before listing occurs. Compared to you we are newbies. Decided to ride a Mercedes not a Lambo for our first big trip down the road. We too are in our 60's. Looking forward to all powered winches,dutchman,every lead aft but still in a boat that we can handle if everything breaks. Keel wet and stick dry- all the best to you and yours


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## PCP

Oregonian said:


> Paulo,
> You claim to have sailed at 6.5k in apparent winds of 18k @ 28degrees. That equals an angle of about 43 degrees and 13k of True wind.
> CONGRATULATIONS: That is the same as an 80 year old Full keel, heavy displacement, 36' William Atkin design.
> What did you say your boat was?


Do yo mean that the hundred year old designed William Atkin's make 35º *true wind* against 2.0m short waves?

Believe in what you want. I would take for an ignorant any person that think that the performance of an old designed full keeler that was not even a race boat in its days can be remotely compared with the performance of any modern performance cruising sailboat. If the boat is specially good upwind the deference will be huge in pointing ability.

Anyway I had said 27/28º. If we consider 27 (the boat was oscillating between 25 and 29 to pass the waves powerfully without losing speed) that is properly a more correct value you will have a true wind speed of 12.6K to a True wind angle of 40.6º. Even if the apparent angle was 28º it would give a true wind of 42º. I have sailed enough boats, including performance boats to know that is a very good performance given the sea condition. My boat is particularly good upwind, it is a modern performance cruiser with 2.25m of draft and Kevlar racing sails.

My previous boat, a 2002 Bavaria 36 was able to do over a plotted coursed course and angle of about 45 degrees (in normal Ocean conditions, not on the ones that I was talking about). I know for experience that the Bavaria 36 pointed better about 5º degrees of what an Oceanis 395 can do.

An Oceanis 395, the one with the deep draft, will outperform by many degrees an hundred years old Wilian Atkin's designed 36ft. My current boat outperform the Bavaria 36 (with long keel and premium sails) by about 8 to 5 degrees, much more in difficult conditions like the ones I was describing.

But of course, anyone is free to think what he wants. Look for a recent thread about pointing ability and plotted courses and you will come back to reality.

Regards

Paulo


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## PCP

outbound said:


> ...It's the largest boat I will ever own and first I would have no concerns about sailing "around the clock". Similar to the Boreal there is a small active market for them. Very few are listed as they are sold before listing occurs. Compared to you we are newbies....


If we come to car analogy your's would be a good sedan designed 10 years ago. Hannas's boat would be a modern four well drive with a powerful engine. I don't think that the performance of the Boreal (except downwind) would be better than the one from the Outbound (as few four will drives will out perform 10 years old good sedan). The difference regarding the Boreal will concern a bigger flexibility, a much stronger hull to impact and the possibility to explore much more safely remote places, due not only by that difference in resistance but also due to its very reduced draft and the possibility of beaching the boat.

Face to bad weather the boat can take refuge at 5 m of the shore where the wind and waves will be much lesser while other boat as to stay 100m away, exposed to much stronger winds and swell. That's why that comparison with a powerful 4 wheel drive makes sense.

Regards

Paulo


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## wolfenzee

A good comparison to 4-wheel drive is people who have 4-wheel drive think they can go anywhere, until they discover otherwise. Most people don't realize the true power and fury nature is capable of.


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## outbound

Paulo- again we will agree to disagree. Would note builder has several orders for Outbound 46s to be built after mine. I've tried to explain to you why this hard fact is true. Boat is much more expensive than buying used.Usually none on used market. Final price about the same as Hannah's excellent boat. Can you explain why repetitively people are making a decision you think is illogical? Of the ones I have been in contact with Outbound owners are educated,forward thinking people not put off by new technologies or designs.


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## hannah2

wolfenzee said:


> A good comparison to 4-wheel drive is people who have 4-wheel drive think they can go anywhere, until they discover otherwise. Most people don't realize the true power and fury nature is capable of.


uke

Wuffy,

You are so out of touch with the 4 wheel cruising world. We are not talking about Most people here! I can tell you that sailors buying expedition boats know what they are doing and have far more experience than most people including you and me. You are always negative in any post you make and always defending your beautiful boat when you don't need to. We know your boat is one of the greatest ever designed. That being said you need to know its limitations and like any of our boats it has limitations, learn them.

Who cares if most people don't realize the true power and fury nature is capable of. I think PCP was trying to compare differences in boat designs. Not about most people, he didn't mention people at all . But seeing you were talking most people, I can promise you that the few who buy 4 wheel boats and high performance cruising boats fully understand the power of nature as they have been seriously sailing a long time. They understand how their boat handles in serious weather and the risks of maybe having to sail in that weather. They also understand they they can't go anywhere only fools think they can go anywhere at any time.

You need to know that 99% of those who are out sailing long distance and know what they are doing far more than you or me do not come to the internet sites. Maybe some day if you ever do set sail you will understand.

You have a great boat but honestly I would rather hear what troubles you about your boat, that way we all can learn something.

Shed boys don't whine.

Cheers


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## PCP

outbound said:


> Paulo- again we will agree to disagree. Would note builder has several orders for Outbound 46s to be built after mine. I've tried to explain to you why this hard fact is true. Boat is much more expensive than buying used.Usually none on used market. Final price about the same as Hannah's excellent boat. Can you explain why repetitively people are making a decision you think is illogical? Of the ones I have been in contact with Outbound owners are educated,forward thinking people not put off by new technologies or designs.


 I like the Outbound. I don't think it is illogical to buy that boat that I consider a very good one. I didn't know that you had bought it new. The only thing I said is that that design is 12 years old and that in my opinion you can notice that.

Comparing with the European market the American market is a smaller and there are a lot less competition in what regards for instance boats like the Outbound. In Europe a brand, even one with expensive boats like HR, Malo, Najad or Southerly could not have the same model for 12 years without updating the hull and keel according with the latest design developments. Costumers would stop to buy that boat to buy more modern ones from the competition. Six years is pretty much the limit for almost all. More than that and the designs become out dated.

That is what I said and I did not wanted to imply by any means that your boat is not a great boat.

Regards

Paulo


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## outbound

Paulo- OK agree different markets also different environments. Still, believe for reasons mentioned before this boat makes more sense for me. Coming from China or France makes little difference to me in New England. Design 1y,15 y or 150y old doesn't matter to me. Only question is this the best boat for the use I am going to put it to.
Wuff- Hannah and Paulo have different knowledge bases and more experience than either of us. I think it wise to respect their opinions. I do agree with you that being driven by the market or desire to have "new and improved" when it doesn't fit your needs does not make sense. I know as a liveaboard we will not be circumspect about weight. We will eventually screw something up and need repairs, things will wear out, we like hot showers (even plumbed for washer/dryer) and AC in the heat, a furnace in the cold we like an easily run boat we understand and is beautiful in ours eyes, we like to cook but cleaning not so much ,we will never do the Southern Ocean, have no interest in high latitude sailing but will catch weather-extreme at times. The new boat is aimed at the market of two people living aboard for extended times and traveling country to country. It allows long term guests but optimizes that type of two person creature comfort cruising without sacrificing much if anything in speed nor seaworthiness. My discussion with Paulo is not about if newer boats are better but what better means. It's in this issue we disagree.


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## hannah2

Outbound,

I like what you said about the market being driven by the desire to have newest and most improved but what we need is what fits our needs. But one thing I noticed in Europe is that sailors are really into sailboats far more than we are here. They have gone sailboat crazy and they have an astounding love about being on the water. They will sail a barn door if they have too, it's just crazy over there. 

Now I'm sure some Europeans are just into new is cool and do not know a square knot from a weather fax. But so many Europeans are really into sailing well and buy their boat for the reasons that fit their needs. Those needs are different than ours in lots of little ways but in the end they sail to the same places as we do. I agree with Paulo that the European market is very sound for new designed boats. Look at the companies having a hard time in Europe and they are the ones more traditional design. If our market in N. America ever becomes strong again it will have to do what Paulo talks about, change designs as quick as new and better ideas come out to make it. Now that said I do not believe that everything new is better and mistakes will be made. 

I love it that the market over there includes good sound sailboats at a price lots of folks can spend. We desperately need that in N. America or else we are not going to have any thing left to buy used or new. 

Let us hope that more people understand what their needs are in a boat and get what they really need. I get a little nervous with our new boat on that note. 

Hope I wasn't too hard on Wuffy but heck I want to know what he really thinks of his boat, the good and the not so good. 

Cheers


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## Faster

Not exactly on-topic but one of the things I like most about Paulo's Interesting boats thread is the exposure to the European market and the different mindset over there.

As a result my 'dream boat' - ie no financial restraints - would in all likelihood be from across the pond..

Hannah.. assume you're going to sail the boat out from Europe when you take delivery? Will she end up back in the PNW?


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## outbound

Was sad to see Malo go down. H - Love your spirit. Looked at a bunch of european boats including yours and some from N.Z./Oz. But the hard work was being honest with myself,accepting all the input from my loved ones, people who work on boats, other sailors and the industry types and thinking about the totality of this purchase not just how the boat moves through the water. Still totally convinced I made the right choice for the Admiral and me.
Hey- if we ever get together - Race ya


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## wolfenzee

hannah2 said:


> uke
> 
> Wuffy,
> 
> You are so out of touch with the 4 wheel cruising world. We are not talking about Most people here! I can tell you that sailors buying expedition boats know what they are doing and have far more experience than most people including you and me. You are always negative in any post you make and always defending your beautiful boat when you don't need to. We know your boat is one of the greatest ever designed. That being said you need to know its limitations and like any of our boats it has limitations, learn them.
> 
> Who cares if most people don't realize the true power and fury nature is capable of. I think PCP was trying to compare differences in boat designs. Not about most people, he didn't mention people at all . But seeing you were talking most people, I can promise you that the few who buy 4 wheel boats and high performance cruising boats fully understand the power of nature as they have been seriously sailing a long time. They understand how their boat handles in serious weather and the risks of maybe having to sail in that weather. They also understand they they can't go anywhere only fools think they can go anywhere at any time.
> 
> You need to know that 99% of those who are out sailing long distance and know what they are doing far more than you or me do not come to the internet sites. Maybe some day if you ever do set sail you will understand.
> 
> You have a great boat but honestly I would rather hear what troubles you about your boat, that way we all can learn something.
> 
> Shed boys don't whine.
> 
> Cheers


I have found myself defending my boat against the people with the "latest, greatest, newest thing on the market is the only way to g" mindset....this thread is about hull design, I have no troubles related with my hull design. Some people might be uncomfortable with the way this boat likes to heel, but that is part of the design. I have yet to "put her through her paces" at sea, though the individual boat and other boats of the same design have racked up and impressive amount of sea miles....I have yet to.....I was told to get everything tuned and ready....then take her out and "beat the snot out of her".....in other words take the boat to it's limits and learn what it can and can't do.

As far as my comment about the 4 wheeling world, I am not commenting on the equipment used but rather the mentality of the people that use it.


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## Classic30

blt2ski said:


> Hmmmmm, so if building an old boat out of newer space age materials is still making it an old boat design......Why the hell are folks building the old "J-Boat" from the early 1900 America's cup boats?!?!?!?!? Or has the rules of the J-class boats changed such that they can? I thought the basic design, specs etc were kept the same, but hulls made of aluminum, carbon spars, laminate sails etc, but still needing to come in using the original design specs of that class.


Good question, Marty. You forgot to mention that building an old J-Boat like this can't be done without a lot more $$$ than you'd need to buy an Oyster!!... 

The answer is that some of these old Class *designs* were almost perfection in themselves (thinking J-Boats, 22-square-metres, 6-metres, Flying Fifteens, Dragons, etc.) and being such incredible fun to race meant that enough have survived over the years in various parts of the world to keep the Class alive. Clever people in the Class Associations then tweak the rules enough to allow advances in materials to be used in construction whilst maintaining the original design (complete with known flaws in some cases!) intact.

If you're curious, have a look around the CIM website.

Even though boat-speed and handling is roughly the same in the same wind conditions, it's a very, very different sailing experience racing to windward in an over-canvassed heavyweight Gentleman's Yacht one day and a lightweight Plastic Fantastic the next - particularly in a stiff breeze. Personal taste.. that's why people spend their fortunes doing it.

Paulo should try it one day.


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## PCP

outbound said:


> Was sad to see Malo go down. ..


What do you mean?

Regards

Paulo


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## outbound

thought I read one of the scandanavian yards was in bankruptcy. guess I got it wrong.- my bad


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## hannah2

Faster said:


> Not exactly on-topic but one of the things I like most about Paulo's Interesting boats thread is the exposure to the European market and the different mindset over there.
> 
> As a result my 'dream boat' - ie no financial restraints - would in all likelihood be from across the pond..
> 
> Hannah.. assume you're going to sail the boat out from Europe when you take delivery? Will she end up back in the PNW?


The interesting boat thread has to be one of the greatest threads on sailing of all time. Eventually I think N. Americans will look to the European market more if they want a new boat. And with the quality of the N. American used market aging and the amount of work required to bring a boat up to where it needs to be it is starting to get slim pickings out there. I'm not talking about 3000 dollar boats but the boats that most want now in the 40 foot range. A lot of them are 20, 30 to 40 years old and getting very tired. The new boat market I believe will pick up not because the economy is picking up but because a lot of people who want to do some serious sailing be it day, coastal or long range cruising will have to take a serious look at all the options available. That's what may have happened in Europe maybe they ran out of good used boats and turned in the other direction. Paulo would know more on that. If N. Americans do start to look to Europe in numbers it can only be good for the new boat market here. Designers and boat building companies here will be encouraged to start up some newer designs and build them. I hope that anyway and I hope they will build quality if it happens.

Faster, I don't know if the new boat will make it back to the North West. We have talked about it as an option but we talk lots of ideas for the next 5 years. But we are taking it one day at a time. If we have plans it will be to leave Europe when the crossing season starts to the carib then through the Canal and back to the Pacific as fast as we need to go. We would like to get up to the Carolines this trip and maybe from there we would decide to head North then East back to the PNW. It would be fun to sail into the Straits after five years away. But who knows, we are really interested in the rivers of Borneo and PNG and maybe from there to S. Africa. We have even talked about hanging out in Europe for a year or if we get through the Panama Canal and have had enough we could bash up to the Sea of Cortez which we love and just becoming Cortez bums like many do. If we were 40 I'd be heading for the high lats, no I guess not! I love the warm sea and the tropical beautiful women.  Someone else can have the polar bears.


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## blt2ski

hannah, Jeanneau and Beneteau are building a number of the 30-40' boats in South Carolina. Although it might be north carolina! do not remember totally off the top of my head. The smaller sizes are not worth the cost to hip across that atlantic. I believe another European company is building stock Mini 6.5 boats in Texas, as again, a 22' boat is not worth the cost to ship across per say. Altho not sure how the Flying tiger 10m was getting shipped across the pacific to here.....none the less one is looking at 10-20K to ship boats from Europe to here in the nw etc. Hence why a number of years ago, beneteau started up the plant in SC, WHen things got slow, Jeanneau joined the plant so both could be better setup to compete here. 36' Jeanneaus the price did close to 20K less for a US built one than one built in Europe. The only thing built here per say is the hull and deck. The wood parts are still made in Europe, but shipped here on pallets and installed. 

But I do agree, I do not really see any US companies that are building anything high tech per say. C&C and Tartan kinda sorta was for a bit......the new 101 looks promising. Santa Cruz has not taken off with any of those newer models that are nice and reasonably fast. Even the New York YC when they had a boat built for them, went with Swan! THere were a few that went after the project, including one NA setup, but even at half the cost did not get the contract! 

In the end, I will prefer a fin over a full'ish keel. ALtho if I could somehow afford an old 12M, would settle for a 6M.......something about one of them.......But for general cruising and sailing, My Jeanneau works fine, altho wish I had a newer version!

marty


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## hannah2

blt2ski, Yes we have a half dozen or so builders and I guess that is better than none at all. When you look at Europe though I see more than that just in the north of France. Maybe Paulo knows how many sailboat companies building boats from 10 meters up in Europe. Most of those companies seem to do well in a crowded market.
I don't think the Europeans have more money than we have at hand and the population base is close to ours. N. Americans love to sail too so I can't understand why our market is so bad. Maybe it is because we have lost our imagination or just isolated, I don't know, I wish I did know the answers. 

When I read the blogs on these sailing forums the folks from N. America are still thinking old design for the most part. Old designs work very well in many cases, I've sailed them for 40 years. But I think we are going to have to get the bug and see what the rest of the world is seeing that we are not. If N. Americans can find out what the Europeans see in the new designs maybe we will get excited enough for adventure capitalists to front the money for new designs and new companies building more outstanding boats here in the new world. I like what they are doing over on Attainable Adventure Cruising in putting together a great seaworthy boat as more of an entry into long distance sailing for $200,000 USA. At least someone is trying hard and if they make it all come true I hope they build them in N. America.


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## blt2ski

Hannah,

Same thing with cars and trucks to a degree, their is the North American market, then there is the REST of the world market. neither is the same overall. You can get a toyota celica last I heard with 4-5 engine options, NONE of which are available here in the NA. Smaller cars wither turbo diesels that get twice the mpg of the NA gas rigs! Or rigs with twice the HP as we have here with better mpg's.......

Boats are kind of the same design build quality if you will to a degree. It an us against them kind of world......now if we can get folks to go metric.......maybe.........

marty


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## jorgenl

outbound said:


> thought I read one of the scandanavian yards was in bankruptcy. guess I got it wrong.- my bad


Najad has filed for bankruptcy


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## PCP

outbound said:


> thought I read one of the scandanavian yards was in bankruptcy. guess I got it wrong.- my bad


Just got the wrong shipyard It is Najad. It has been bought since then but they are not out of trouble. They had a very good time before the crisis and increased the size of its operation making the shipyard bigger and hired more people. Bad timing.... the crisis struck immediately after that.

Besides this is a classic case of what I was telling you about a need to continuously keep improving the boats in a very competitive market: Najad are great boats but their rate of innovation and up grade of the boats was just not keeping up with the competition ( HR, X yachts cruising line and Malo) and clients started to disappear). The problem is not quality or the interior it is sail performance and the ones that think that does not count even on luxury cruisers are wrong, at least in Europe.

The guys that bought that, a motor company did not done what was needed: Or firing 2/3 of the staff and have a very small firm making high quality conservative boats, for a very small clientele or investing massively in one or two new new up to date models and keep the staff competing for the main market in the Luxury cruisers segment.

I guess they didn't have the means for the second one and labor laws in Sweden prevented the first one.

Regards

Paulo


----------



## PCP

blt2ski said:


> ....
> But I do agree, I do not really see any US companies that are building anything high tech per say.....
> 
> marty


Marty I guess you forgot J boats the American boat that is more sold in Europe than in the US

For some of the most interesting models they just make them in France. I mean not in the US and France but only in France. If you want a J122, one of my preferred boats, they just ship you one from France

Also I guess we can consider Corsair trimarans hig-tech boats. The only problem with Corsair is that they are in the US. I guess that they should do the same as J boats and move to Europe, at least for the bigger boats. I am sure the sales would increase substantially.

The problem in the US is the market I mean the proportion between motor boats and sail boats. Guys that have money buy in America a hugely bigger proportion of motor boats compared with sailboats.

Some years ago I had a look at all Boat show data in what concerning the percentage of sailboats compared with motorboats and the difference between Europe and US was huge not 2 times less, maybe 10 times less. That is the real problem. You need money, lots of it flowing to have a flourishing market. You need that the guys that have the money to change his boat anytime a more faster or nicer boat comes to the market start to buy sailing boats instead of motorboats or fast cars.

Without that you will not have a competitive market. imagine what would happen to the American automobile market if many didn't change for a new ride after 3 or 4 years and started to maintain and recover 20, 30 and 40 years old cars. Imagine all those huge car junkyards empty and all those cars circulating. Can you imagine what would happen to the competitiveness of the American car Industry face to others where they ditch older cars on a junkyard and keep buying new cars? I mean regarding means for innovating and researching?

I guess that is the American problem in what regards sailboats competitiveness: General interest in sailing.

Compare interest in sailing in US and France and you will understand why sailboat industry is so big in France and why the market is so competitive. Not only in France. The interest in Sailing in Italy and North of Europe is also big. Look at a small country like Denmark and look at the huge production of high quality top sail boats: X yachts, Dragonfly, Luffe, Nordship, Nordborg and I am sure there are much more small companies that I don't know about. Imagine that on a country with a bit more than 5 million people and you get the general picture.

Regards

Paulo


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## outbound

Beyond the boat another problem for US buyers is the totality of trying to spec a semi custom boat built in another country, coordinating sale of prior boat, importation,warrenty work, insurance,financing and service after sale etc. Large production builders like B+J have this worked out but smaller builders-not so much. Making multiple varied innovations to accomendate my 6' and wife's 4'10" as well as sourcing from around the world was easy with Phil.Walking through the "soft costs" and making use of cheap money with investment returns much higher than loan money was easy working with people here. Don't think that will be the case until the infra structure for boat building beyond just the molds and tooling in the US is once again established. Valiant had a 35y run with boats that were little changed in basic design in large part because they did it once and did it right. This occurred at a time of massive innovation in N.A.s thinking and the US market was hot.


----------



## blt2ski

Paulo,

I would agree that J-Boats is probably building a reasonable high tech newish boat. Even still, when you look at the new models, it is J-boat. Look at Elan and Beneteau for two, and they have boats that cruise, then some race, and a couple do both to a degree. X-Yacht is getting into this mold now that they are getting bigger per say too. 

Most of the J's I see around puget sound any how, are the what I would call more full bore racers, 105's for example. There is still sorta a J30 class still racing, lots of 24's, just enough 109's to make a 1d race every two yrs or so. I ca say the same for the b 36.7......C&C 115......mybe all of 7 or 8 in the whole of the salish sea.

But I would say most buy PB's here. As the wind will be light enough, or yo have to fight currents, that to get anywhere, you motor a lot! I know of one fellow that has been racing his 40' IOR style boat for 20 some odd years, he is looking to get a mid 40' sticker to cruise in! makes better time to and from etc. He can get a nice set up one for less money with more space than an equal sailboat. altho it doe cost way mre to operate........

marty


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## daledog

Depends on where you sail. If I was doing an ocean passage I'd want a full keel, a fin in heavy seas is much more apt to be squirrelly. If you are not on open seas a fin is much more maneuverable. I had a Cal 9.2 that turned on a dime. But in big following seas one must be really be diligent at the helm. It's a great deal of work. The above 3/4 keel and skeg hung rudders are a good compromise. I plan on blue water cruising, Bermuda...ocean crossings. My choice for that is full...


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## outbound

would note boat like Hannah's with dagger boards aft are said to track wonderfully in following sea. My new boat given hull shape aft and rudder design also is known to track and surf without issue. Properly designed bulbed fins and modern centerboards with daggerboards seem to have this issue solved. Ability to point and made good days run in light/moderate air remain failings of most full keeled boats. Keeping boat comfortable at or beyond hull speed remain favorable attributes of outbound,boreal and modern crop of euro boats.


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## PCP

blt2ski said:


> Paulo,
> 
> I would agree that J-Boats is probably building a reasonable high tech newish boat. Even still, when you look at the new models, it is J-boat. Look at Elan and Beneteau for two, and they have boats that cruise, then some race, and a couple do both to a degree. X-Yacht is getting into this mold now that they are getting bigger per say too.
> 
> ...
> marty


The J122 is a performance cruiser that can race while the J111 and J105 are more of a racer.

The only reason that prevents J boats to make what Xyachts do, with a full line of racers, performance cruisers and cruisers is ....MARKET, I guess. Simply there is not a big enough market for more expensive and fast sailboats in America.

Some time back I talked with the Salona guys regarding the American market. They said to me that they were more interested in the Asian market that was a lot more interesting. They had only sold a boat to America but several to Asia and Australia.

The owner of that American Salona 37 is a member of this forum. He says wonders about his boat and even so they only managed to sell one

Regards

Paulo


----------



## hannah2

daledog said:


> Depends on where you sail. If I was doing an ocean passage I'd want a full keel, a fin in heavy seas is much more apt to be squirrelly. If you are not on open seas a fin is much more maneuverable. I had a Cal 9.2 that turned on a dime. But in big following seas one must be really be diligent at the helm. It's a great deal of work. The above 3/4 keel and skeg hung rudders are a good compromise. I plan on blue water cruising, Bermuda...ocean crossings. My choice for that is full...


Daledog, Many of us here in N. America thought the same as you and most still do about the full keel/fin keel in heavy seas etc. But like outbound said those ideas are outdated. The new designed boats being built over in Europe have solved those problems for open ocean crossing. And we here in N. America still remain clueless that for the last 10 years on the other side of the pond they have been enjoying wonderfully built boats that behave better in many ways than our traditional boats on all points of sail in big water as well as small water.

Boy if you have not read the "interesting boat" post take a look at it there is lot of good stuff in it.

cheers


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## Lou452

Are the race boats of the past ready to become a cruiser? Will J-111 and J-105 be converted or junked? What do you see as options for sailors that are in the Nth / Sth America? Good day, Lou


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## PCP

Regarding J boats there is many times a big confusion and with a certain reason:

The boats have a similar look and contrary to other brands that somehow identify by the name racers and performance cruisers( like for instance Xyachts that have XR, XP and XC), J boats don't do it, they just are J boats, racers and performance cruisers alike.

But if you look at the interiors it is easy to separate racers from performance cruisers:

J105



















J111



















J109




























J122




























J133



















So, yes, you can cruise in a J105 or J111 but even if they have the minimum indispensable (they are offshore racers) you can only do that in a spartan kind of way.

The J109, J122 and J133 even if they were utilized mainly for racing have a good cruising interior, can cruise comfortably like that and they can be easily improved with added tankage and some minor improvements. They are a great base for a great a seaworthy and fast performance cruiser and with some luck they can even have been rigged already that way.


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## mergens

I have a Crealock designed Dana 24. It has what can be considered a full keel, but with the foremost section cutt away. Despite their small size,these boats are exceptional for their ocean going capability.

I,ve sailed sevaral fin keel designs in deliveries and have noted their less than stellar behavior when beating into head seas. The relatively flat hull shape forward makes hard slams rather than slicing through the seas. Big shakes and slams are indications of stress and have got to be more fatiguing structurally


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## Lou452

Forgive me for getting off topic Finn vs full. One of the advantages I see to the modern fin keel boat is not using wood. Why do they take a J- boat sparten as it is and put wood inside? Will this not increase the amount of work needed to maintain the boat? The EU from what I am looking at likes to use more wood below decks ? The craft work and detail is very good. I would like plastic fiber glass and limited SS. 
My dad had a wood boat. Winter for me as kid was spent on my back sanding. I do not want to sand , stain, varnish, paint any more wood unless the pay rate is great. Good day, Lou


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## blt2ski

Lou,

Generally speaking, the interior wood is not an issue from a maintenance standpoint. I re varnished all the interior of my boat 4 yrs ago, that was the first coats of varnish since it was new 20 yrs before. now outside on deck etc......oh yeah, any wood will need some work every year or two or three depending upon the type, how you want it to look etc.

marty


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## Oregonian

Daledog, since your posting I have observe a number of ridiculous comments concerning ocean going boats. Your reference was a cal 9.2. A 30 footer. I know exactly what you are referring to as I have a lot of experience with this and many other similar sized boats. The most ridiculous of the comments? Hannah2 said “The new designs being built in Europe have solved those problems for open ocean crossings” Another by Outbound, “ability to point and make a good days run in light/moderate air remain failings of most full keeled boats. PCP? Too numerous to bother with. ON THE SMALLER BOATS that are used for long distance sustained cruising, the problems created by the ocean have not been solved by any of the new boat designs. As the boat gets lighter, it gets less comfortable – Do not take this lightly. As the boat becomes heavier with the 3000# of stuff you need, the boat becomes much slower. In fact, it will become slower than the boat that was designed heavier in the first place. A heavier full keeled boat is sailed differently in light air than a lighter fin keeled boat. It can get the job done just as well. For anyone on this forum or elsewhere to imply that a full keel boat cannot point as well in the ocean as an equally ladened fin keeled boat, in the smaller sizes, is either very inexperienced, ignorant, or pushing some other agenda.
At the very least, the comments made by Paulo and some of the others, fall into the Gross Exaggeration category. Pointing angles and speed of the smaller, heavily ladened sailing boats has improved Very little in the past 80 years. For the most part, if some boat is doing something better than another then it is also doing something worse than another. There is simply no over-riding benefit to crossing an ocean, Down wind or Upwind, in light wind, or heavy air, on a fin keeled, or light weight, ocean voyaging, live-aboard, cruising sailboat.


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## outbound

Oregonian- You make some comments which have merit and some which do not. My new boat has a solid glass hull and 28,000 displacement. Most of that weight is in the center of the boat with 200g of fuel and 200g of water under the saloon sole. It flies but is no light weight flier. The design request was for fast cruising with the assumption extra weight in the form of stores and machinery would be put aboard. It will and has massively outperformed older full keeled designs in myriad open ocean crossings. It is more comfortable in every way as c/w older full keeled designs. However, you are right a boat is a complex system and moderation so no flaws are extreme requires limiting the benefits of other design elements.Schumacher added weight (and expense) in the engineering of the design so that in all critical areas the working loads are meer fractions of the load to failure. Paulo and Hannah 2 are right that there have been significant performance benefits in the last 10yrs. but I believe some come at a cost of liveability of the boat.Use of modern materials and engineering ( scrimp infusion techniques,carbon,spectra etc.) have not resulted in decrease in strength or safety. Boreal mailed me a cd and we communicated through the net. I was psyched to take the trip to france and investigate futher. I had no issue at any level with the boat but when my wife said "I can't live on that boat" unfortunately it was off the list. She saw multiple Outbounds with multiple different interior plans. She went sailing on one. On the drive back- I love it, it's beautiful,rides so nice,I feel so safe,everything is where it needs to be. Done
One could say a bristol channel cutter at 28' or my beloved PSC34(not full keeled) make sense as proven small "blue water" boats but in the 35-50' range for open water full keeled boats no longer make sense.


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## PCP

Oregonian said:


> Daledog, since your posting I have observe a number of ridiculous comments concerning ocean going boats. ...
> 
> The most ridiculous of the comments? Hannah2 said "The new designs being built in Europe have solved those problems for open ocean crossings"
> 
> Another by Outbound, "ability to point and make a good days run in light/moderate air remain failings of most full keeled boats.
> 
> PCP? Too numerous to bother with. ON THE SMALLER BOATS that are used for long distance sustained cruising, the problems created by the ocean have not been solved by any of the new boat designs. ...
> 
> For anyone on this forum or elsewhere to imply that a full keel boat cannot point as well in the ocean as an equally ladened fin keeled boat, in the smaller sizes, is either very inexperienced, ignorant, or pushing some other agenda.
> 
> ....
> There is simply no over-riding benefit to crossing an ocean, Down wind or Upwind, in light wind, or heavy air, on a fin keeled, or light weight, ocean voyaging, live-aboard, cruising sailboat.


Jesus you seem pretty convinced at what you are saying. The fact that nobody with enough money to buy a new cruising sailboat is having one, the fact that no NA is proposing a new designed full keeler, the fact that no production shipyard is offering any does not makes you suspicious of your certitudes?

Certainly you think that guys that circumnavigated like Hannah or even more experienced sailors that once had full keelers for bluewater cruising and today chose fin keelers are hugely mistaken in their choices and don't know the advantages of a type of boat over another.

Certainly you think that all the companies that make offshore boats that once proposed to their clients full keels, then modified fin keels and now fin keels don't know what they are doing and the same with their clients that are just mislead by devious propaganda from guys like me, a master conspirator.

There is out there a vast conspiracy against full keel boats a conspiracy that one day will be fully exposed by guys like you

You talk generically but give a stronger incidence on smaller boats. Yes, a smaller heavy boat, full keel or not, it will be more seaworthy than a light boat of the same size. But who wants a cramped slow heavy small boat if by the same price it can have the same seaworthiness in a much bigger light sailboat that it will be much faster, as comfortable with a much bigger interior space? (size matters to sea motion as well weight to price).

That is what discovered Northshore one of the last to make small heavy blue-water cruisers before given up and turn to more modern bluewater cruisers. Northshore discovered that soon enough to survive, all the other that persisted bankrupted. This does not tell you nothing, besides the conspiracy theory?

Regards

Paulo


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## Jeff_H

I have read many of Oregonian's posts in the past few years. Clearly he is very experienced and fully understands the strengths and weaknesses of full keels. Based on his comments, he knows his boat, and has learned how to work around most of its liabilities to a level which is acceptable to him. In these discussions, he frames his arguments in a way that is consistent with his wants and needs in a boat. I admire all of that. 

But in these kinds of discussion often the gaps between the presented points of view come down to how each person frames the argument. So for example, in Oregonian's post above, he rightly points out that offshore capable distance cruisers need to carry a lot more 'stuff' than a coastal cruiser, and that the amount of excess carrying capacity is generally proportionate to the displacement of the boat. He is correct in saying that a lighter boat will have a more limited excess carrying capacity, and to some extent, certainly when considering heave, a lighter boat will have a less comfortable motion. So, by setting up the discussion the way he does, if comparing boats of the same length on deck and similar waterline length, the boat of the heavier dry displacement would in theory have greater excess carrying capacity and a more comfortable motion.

But here is the short-coming of framing the argument in that manner. If we compare two boats of equal displacment, the modern design will be comparatively much longer (perhaps 20-40percent) on deck and waterline than a so-called traditional heavy displacement cruiser. And so if we were compare a modern design to a traditional design of equal displacement, the modern boat's longer water plane, better dampening, higher roll moments of inertia carried lower, greater stability and consequently, greater sail carry capacity will result in a boat which offers better seaworthiness, motion comfort, stability, excess carrying capacity, ease of handling, performance in all conditions, at a similar initial cost. But all that comes with the liabilities of higher slip and hauling costs, and deeper draft. 

In other words, in my mond, neither side is wrong as each poster is framing the question. 

Respectfully,
Jeff


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## GBurton

PCP said:


> Jesus you seem pretty convinced at what you are saying. The fact that nobody with enough money to buy a new cruising sailboat is having one, the fact that no NA is proposing a new designed full keeler, the fact that no production shipyard is offering any does not makes you suspicious of your certitudes?
> 
> Certainly you think that guys that circumnavigated like Hannah or even more experienced sailors that once had full keelers for bluewater cruising and today chose fin keelers are hugely mistaken in their choices and don't know the advantages of a type of boat over another.
> 
> Certainly you think that all the companies that make offshore boats that once proposed to their clients full keels, then modified fin keels and now fin keels don't know what they are doing and the same with their clients that are just mislead by devious propaganda from guys like me, a master conspirator.
> 
> There is out there a vast conspiracy against full keel boats a conspiracy that one day will be fully exposed by guys like you
> 
> *You talk generically but give a stronger incidence on smaller boats. Yes, a smaller heavy boat, full keel or not, it will be more seaworthy than a light boat of the same size. But who wants a cramped slow heavy small boat if by the same price it can have the same seaworthiness in a much bigger light sailboat that it will be much faster, as comfortable with a much bigger interior space? (size matters to sea motion as well weight to price).*
> 
> That is what discovered Northshore one of the last to make small heavy blue-water cruisers before given up and turn to more modern bluewater cruisers. Northshore discovered that soon enough to survive, all the other that persisted bankrupted. This does not tell you nothing, besides the conspiracy theory?
> 
> Regards
> 
> Paulo


Paulo, maybe something is being lost in the translation here...I think where you cross the line is when you make untrue statements about other boats, some of us are trying to tell you is that we have a different opinion. Many of us don't need to be convinced by you as to what boat we like, because we have already found out through experience what we like.


----------



## PCP

GBurton said:


> Paulo, maybe something is being lost in the translation here...I think where you cross the line is when you make untrue statements about other boats, some of us are trying to tell you is that we have a different opinion. Many of us don't need to be convinced by you as to what boat we like, because we have already found out through experience what we like.


Liking as nothing to do with a boat performance. I like traditional boats (full keel boats) and classic boats. They sail with a lot of character but if we look at performance as a sailboat (and I am talking about global performance, not only speed) they simply don't perform as well as modern fin keel boats. That is why NA don't design full keel boat anymore, whatever the use the boat is going to have, except if it is a replica of an old boat.

Please quote me regarding those untrue statements. You should not say that somebody say untrue things without referring exactly those things.

Regards

Paulo


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## Argyle38

PCP said:


> Liking as nothing to do with a boat performance. I like traditional boats (full keel boats) and classic boats. They sail with a lot of character but if we look at performance as a sailboat (and I am talking about global performance, not only speed) they simply don't perform as well as modern fin keel boats. That is why NA don't design full keel boat anymore, whatever the use the boat is going to have, except if it is a replica of an old boat.
> 
> Please quote me regarding those untrue statements. You should not say that somebody say untrue things without referring exactly those things.
> 
> Regards
> 
> Paulo


Being the "performance" is a subjective term, I would say liking a boat has a lot to do with performance, as defined by the boat owner.


----------



## PCP

Jeff_H said:


> ...
> But in these kinds of discussion often the gaps between the presented points of view come down to how each person frames the argument. So for example, in Oregonian's post above, he rightly points out that offshore capable distance cruisers need to carry a lot more 'stuff' than a coastal cruiser, and that the amount of excess carrying capacity is generally proportionate to the displacement of the boat. He is correct in saying that a lighter boat will have a more limited excess carrying capacity, and to some extent, certainly when considering heave, a lighter boat will have a less comfortable motion. So, by setting up the discussion the way he does, if comparing boats of the same length on deck and similar waterline length, the boat of the heavier dry displacement would in theory have greater excess carrying capacity and a more comfortable motion.
> 
> ...
> Respectfully,
> Jeff


Yes, of course you are right but displacement of a sailboat has not to do with Long keel boats neither with Fin keel boats. Keels are what we are discussing not displacement. That is true that full keel boats tend to be more heavy than fin keel boats but that is not always true, neither necessarily true.

There are full keel boasts relatively light and fin keel boat heavy. What I am saying is that a fin keel is more efficient than a full keel, not discussing light displacement versus heavy displacement. And I am not saying either that there are not well designed full keel boats and badly designed fin keel boats.

Take for instance the Vancouver 36, a fin keel boat that succeeded to the 34ft Vancouver (the 34 was basically a bigger 32 and the design is 30 year's old).

The 34:










and the 36:




























When Taylor, from Camper & Nicholsons updated the design of The Vancouver 34, making it a 36 footer, altering the full keel to a fin keel and providing the boat with a more efficient hull, he didn't want to make a different type of boat. The type of boat is the same: a relatively heavy small blue water boat. He just wanted to make a better and more efficient sailingboat with the same basic characteristics. Regarding weight the fin keel boat is even proportionally heavier even considering that the 36 is two ft longer( 6.350kg to 9.260kg).

I am quite sure that if he designed a new updated version now, even if he maintained the weight, the shape of the of keel and ruder would be different and more efficient. Boat design is improving all the time and that has nothing to do with heavy or light boats or the type of boat (use) but with efficiency in what regards sailing in what concerns different boat uses.

Weight is a negative factor in what regards sail efficiency but when we want to make a small boat more seaworthy weight continues to be an important factor. For almost all it makes sense to have a bigger boat with the same weight of the smaller one with an increased stability and speed for about the same price but as you say each case is a case and one can prefer to have an heavier smaller boat for economic reasons linked with maintenance and marina prices. However the market shows that those sailors are very few and that kind of boat is almost nonexistent, I mean small heavy cruisers with offshore capacity on the new boat market.

Regards

Paulo


----------



## outbound

Paulo- just curious what do you think of Morris, Waterline,the more recent Shannons , the new PSC ketch. These are fairly substantial boats. There is a reason that even at a given LOA some folks still prefer a heavier, more substantial boat.This does not relate to construction method, length of boat or expense. Hope you would agree is it easier to get a performance multihull to go faster but for many they just don't make sense and they build anfd buy monohulls. Similarly, as a total experience performance as you define it is not the only parameter that goes in to the boat purchase. I find some features- especially the interiors of euro rockets ugly and not satisfying as regards ergonomics, expected aesethic enjoyment in fuure years and ease of maintenance. Te interior of my boat fo me is a warm, inviting place that will serve me and my wife into our 80s. We give up little or nothing in meaningful performance ( you have seen the polars and they remain outstanding). I agree with you the bulbed fin keel is a major advance. But some will say I don't want more than 6.5' in draft. Idon't want bulb extending in front of the fin. I don't want twin rudders. I do want my boat overbuilt and functional for me. That's why you see people with far more resources than me still buildng one offs you would deem conservative. You asked about aluminium in the past . If I had the resources I would die and go to heaven owning a K+M. Once again a design of well over a decade old.


----------



## outbound

Paulo- just went to the K+M website. They have two Bestewind 50s under construction. Can I tell you my birthday(GRIN)? Be you're best friend. Please..........

with respect and regards- just pulling your leg.


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## PCP

outbound said:


> Paulo- just curious what do you think of Morris, Waterline,the more recent Shannons , the new PSC ketch. These are fairly substantial boats. There is a reason that even at a given LOA some folks still prefer a heavier, more substantial boat.This does not relate to construction method, length of boat or expense.


Sure, an heavier boat has nothing to do with full or fin keel or up-to-date hydrodynamics. In fact I prefer the design of the Outbound 44 to any of those boats. Some are really outdated like the Shannons and Pacific Seacraft other are slightly outdated like the Morris or the Waterline and I don't mean the interior but hull and keel design. In fact the only ones that are modern are the Classic line of Morris, that have modern under-bodies. That does not mean that they are not high quality boats with great interiors, all of them, in fact I can only judge then by the photos and reputation that is generally very high (as the prices).

Regarding the Outbound my opinion is that it is a remarkable good design for one 13 years old. I like the interior that seems to be of high quality, if a bit classic for my taste, the boat is not heavy and it has a decent sail area for that kind of boat. I am quite sure that if Carl Schumacher was still around he would be the first to want to update his design. The ballast effect could be maximized (only 30% is on the bulb) providing a more stiff boat and even if in what regards rocker the boat seems very modern, the shape of the hull shows some age and the beam could be brought more aft. Nothing big, but small improvements that would make for a better boat. I like the boat moderated beam. All in all, as I have said already, the Oubound 44 is a great boat.



outbound said:


> Hope you would agree is it easier to get a performance multihull to go faster but for many they just don't make sense and they build anfd buy monohulls.


Of course.



outbound said:


> Similarly, as a total experience performance as you define it is not the only parameter that goes in to the boat purchase.


Just to be clear, it is not as I define it. When I talk about performance here I am not talking just about speed, but pointing ability, stability downwind, sailing with less (or more heel), sea motion comfort, light wind performance, strong wind performance, reserve stability....all the factors that makes a sailboat a good sailboat in what regards its basic function: to sail and to sail well and safely. Different types of boats (for different uses) have different valuations in what regards the relative importance of these parameters.

We can also consider that the other function of a cruising boat is to provide a home, so we can also talk about performance in a way the boat satisfies better or worse the main requisites: Quantity and quality of the space, functionality, storage, tankage and so on. Again, different types of boats value these qualities more or less in what regards the sailing potential and most of the times these qualities (interior comfort) are detrimental to sail potential.



outbound said:


> I find some features- especially the interiors of euro rockets ugly and not satisfying as regards ergonomics, expected aesethic enjoyment in fuure years and ease of maintenance. Te interior of my boat fo me is a warm, inviting place that will serve me and my wife into our 80s. We give up little or nothing in meaningful performance ( you have seen the polars and they remain outstanding).


And then it is me that make generalizations
If you want to compare, compare your boats with what is comparable in terms of price and in what regards that we are talking about boats that have probably a slightly better performance, at least some, but I would not call them rockets and the quality of design and finish is as good as the one in your boat. We are talking about HR, Najad, XC Yachts or the likes.



outbound said:


> I agree with you the bulbed fin keel is a major advance. But some will say I don't want more than 6.5' in draft. Idon't want bulb extending in front of the fin. I don't want twin rudders. ..


Sure, all cruising boats that are in the same class of yours have about that draft as standard and can have an optional reduced draft that will off course diminish the upwind performance.

About the twin rudders you left me confused. Why the hell you don't want something that will just add more control to your boat, will sustain less stress (and therefore will be more resistant) offer a double safety factor in the case one of them is hit by something (with one if you break it you are in trouble) and adds not more drag to the boat?

Regards

Paulo


----------



## PCP

outbound said:


> If I had the resources I would die and go to heaven owning a K+M. Once again a design of well over a decade old....
> 
> Paulo- just went to the K+M website. They have two Bestewind 50s under construction. Can I tell you my birthday(GRIN)? Be you're best friend. Please..........
> ..


KM is Dutch a builder specialized in Aluminium. They build from several NAs and even if they purpose some models it is much a custom boat. They also make custom boats.

The Bestewind 50 is a very recent design from Gerard Dykstra that has a huge talent in designing modern boats that looks like classics. The boat was one of the nominees for the 2012 European boat of the year on the luxury class (last year).






Ok, I give you that one and you give me this one





Regards

Paulo


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## Oregonian

PAULO, have you confused Oregonian with Jesus? Earlier I was just an “ignorant” Am I now an “ignorant Jesus”? 
The reason I point out the sailing qualities of some full keeled boats is to help balance your gross exaggeration of the modern designed fin keeled boat. You have been misleading people on this forum (and others) for way too long. You have done many people a disservice with your claims. The change in design to a fin keel does NOT make all boats better. It will not insure that the boat will sail better in all cases. A short, heavy, boat with a fin keel will get pushed around in a twisting and rolling fashion a lot more than a boat with a full keel. If a boat is a full time, live-aboard, long range, cruiser, it will be a heavy boat; fin keel or not.
I have never, at any time, stated that all boats, of any length, benefit from having a full keel. I have always referenced “Smaller” boats, ie, 20 to 35 feet or so. I will say this to you for the 3rd time: The short, heavy, full keel, live-aboard/voyaging boat, will out perform the fin keel counterpart, in just about any condition.
PAULO, I sail a lot. Way more fin keels than full. Many boats “Right out of the box”. Where do I get my data? Frequently under the palm tree at the end of a long passage. If 2 boats leave port together and the Westsail 32 arrives after 19 days and the Pretorian 35 after 21 days, Well, that’s data. Repeat the scenario about 27 times. More data. Repeat similar scenarios about 130 times. More data. Throw in a few long distant races. More data. (Well over 1000 local sails - more data). The result: There is very little to merit the fin keel boat when used on the “SMALLER” sizes of long distance cruisers.
FASTER has said it is important for him to maneuver well in reverse. That is a good reason to own a fin keeled boat. Lin and Larry Pardey’s boat probably does not maneuver well in reverse. Are they “Ignorants” too?

One more thing: Please try to understand this. A person that buys a Dana 24, or a Westerly Centaur at 26’, or a Cape George 31, or a Westsail 32, probably did not secretly want a 40 to 50 foot boat. Some of you insist on comparing similar displacements of boats. That is your right, and some people will do that, but please don’t assume that all people want a longer boat. They do not.
outbound, I am familiar with the outbound 46. I am certain it is a great boat for you and your wife. Good luck, see you down the road. I will be in Raiatea in 4 weeks


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## outbound

Perhaps I'm mistaken but I thought the 50 was a boat Dystra drew for himself ~10-15y ago for high latitude sailing. I thought the conversion from aluminium to glass was the recent event. Both are sweet boats but the interiors of some of the metal ones are gorgeous. He also drew a 45' version. Put a lifting keel in that and you have it covered for me.
Paulo- If you sailed in New England much you would not ask your last question. A lobster pot line isn't going to break a single or double rudderpost. Hell you could pick up my boat by it's rudderpost. Often when sailing with any kind of sea at night you see them at the last second. Dodging pick up buoys is a New England sport. May be wrong but over half the boats you mention are single rudder. Tried to get the features I wanted ( no metal tanks, no keel bolts, no portlights in the hull, no balsa etc.) and the layout modified - Outbound met these desires- others did not.
O- Hang in there kiddo. Just realize P+H have a lot of experience too. Wife saved up and brought some stress ease chairs. Have a rocker (design over 100y old). Guess which one I like after a hard days work. Still, sleep in a pencil post bed I made myself. My clothes are in a highboy I made from a 150 year old design. They work, are beautiful in my eyes and warm my black heart.(grin)


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## outbound

O- ?at what LOA do you think the break from full to fin occurs?


P.S.- due to family expect to come back to N.E. time. to time. Still, gonna break my heart to have to empty the house.


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## PCP

Oregonian said:


> ..If a boat is a full time, live-aboard, long range, cruiser, it will be a heavy boat; fin keel or not... There is very little to merit the fin keel boat when used on the "SMALLER" sizes of long distance cruisers....
> I have never, at any time, stated that all boats, of any length, benefit from having a full keel. I have always referenced "Smaller" boats, ie, *20 to 35 feet* or so. I will say this to you for the 3rd time: *The short, heavy, full keel, live-aboard/voyaging boat, will out perform the fin keel counterpart, in just about any condition.*


Woah, that is some particularization: So in your opinion full keel boast are only better if they are cumulatively:

*Short heavy small boats, long rage cruisers intended for voyaging or living aboard.*

That is particularizing almost ad infinitum  Yes I agree that is the situation where a full keel loses less to a fin keel boat. That particularization of a boat is so narrow that on the huge European market with thousands of different boats proposed to different sailors I don't know of any modern design that fits the bill. But I do know of small heavy boast particularly suited for living aboard: the Sirius line, but they are fin keel boats:

The 31 and the 35:













Oregonian said:


> .. Some of you insist on comparing similar displacements of boats. That is your right, and some people will do that, but please don't assume that all people want a longer boat. They do not.


Regarding small heavy boats compared with bigger sailing boats with the same weight and the same load capacity, it seems you didn't understand the point:

I explain the logic of that comparison: Budget, function and the price of the boat.

In boats with similar quality, weight more than size is a price indicator. Heavy small boats like the Sirius or the Vancoeuver (that was proposed till recently) cost the price of a much bigger lighter mass production sailboat. The Sirius 31 costs the price of a 37/38 mass production boat and the Vancouver 36 the price of a 42ft boat. The load each boat can carry, the smaller and the bigger one with the same price, are about the same but the bigger one offers a lot more interior space and space, as carrying load, is a much needed commodity to live abroad. The bigger boats are not only more comfortable in a seaway and safe or safer than the smaller ones.

There could be people that for the same budget would chose the smaller boat for living aboard but, as the market shows, that would be a small minority.

Of course, the used market, particularly the used market with very old boats introduces all kinds of distortions and it is possible that this price comparison does not apply anymore. Probably the heavy small boats devalued more than the bigger boats that once had the same price and now they cost less than bigger lighter boats that once costed the same.

We are talking about design and about Full Keel versus Fin keel and what matters regarding that is the state of the art, meaning modern boats and the efficiency of one system versus the other, not what you can find on the used market. In what regards the used market you have a limited choice and in some cases a full keel boat can be a better choice over a given fin keel boat.



Oregonian said:


> ... I have observed a number of ridiculous comments concerning ocean going boats. ...
> 
> The most ridiculous of the comments? Hannah2 said "The new designs being built in Europe have solved those problems for open ocean crossings"
> 
> Another by Outbound, "ability to point and make a good days run in light/moderate air remain failings of most full keeled boats.
> 
> PCP? Too numerous to bother with. ON THE SMALLER BOATS that are used for long distance sustained cruising, the problems created by the ocean have not been solved by any of the new boat designs. ...
> ....
> There is simply no over-riding benefit to crossing an ocean, Down wind or Upwind, in light wind, or heavy air, on a fin keeled, or light weight, ocean voyaging, live-aboard, cruising sailboat.


Regarding this, when Hannah is talking about he is referring to bigger boats, boats that eventually cost the same price of the smaller heavy boats with living aboard capacity and he is referring to new designs. On the European market everybody that goes voyaging will prefer a bigger boat than a proportionally much heavier smaller one that costs the same and has a much inferior sail performances.

You assume that everybody that goes for long distance voyaging and extended periods of living aboard travels and lives with a lot of stuff. On this days of watermakers and digital information it can be otherwise and some that voyage do that on modern small light weight sailboats and those boats with an adequate charge will outperform in a stellar way any old designed small heavy weight full keeler, in 95% of the conditions.

I guess that a pleasure circumnavigation counts in your book as voyaging. Look at this couple on a 33ft boat that had crossed the Atlantic with an average well over 7k and are completing now his circumnavigation. On the passage between Cape Town and Bahia his average speed over the ground was 7.7K. And we are talking with a boat with a crew of two, the skipper and his wive.






I will not generalize saying this boat and travelling light and enjoying this kind of life will suit to all. You should do the same regarding saying: *"There is simply no over-riding benefit to crossing an ocean, Down wind or Upwind, in light wind, or heavy air, on a fin keeled, or light weight, ocean voyaging, live-aboard, cruising sailboat."*

Regards

Paulo


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## outbound

Paulo- Your posts here and on the the other thread reflect a difference in the US v. European markets. Here in the rat race of the US there is a niche of sailors who although they have sailed their whole lives can only now in their 60s and 70s go cruising. They want to crusie the San Quins,east coast of US, the Carribean, the South Pacific, the Hebrides, the west coast of europe and north coast of the Med. THEY DON'T WANT TO GO VOYAGING. THEY WANT TO GO CRIUSING. They will make use of those advances that improve the quality of their lives. Comforts and aesethics are just as important to this group as performance. To paraphase Crealock-the "voyage" should equal the joy of the arrival. Have lots of screen on my boat-stll rather read a book.
The US water tourists don't have the same outlook as the 30 to 40 somethings taking off from europe.


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## wolfenzee

I concede......I now realize it is impossible to defend a boat of my own personal taste against someone who feels that anything other than their personal taste, the "latest, greatest, cutting edge"(what ever that the marketing industry is pushing at the time) is an inferior boat.


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## PCP

outbound said:


> ...
> The US water tourists don't have the same outlook as the 30 to 40 somethings taking off from europe.


Most Europeans, unless they can take a sabbatic year, will only do extensive cruising at the retirement age that is for most mid 50's and now it is about 60 year's old, even not taking full pension.

Till then they do club racing, week end cruising or holiday's cruising and mostly they charter boats.

I knew a more than 70 year old guy that was cruising along on a Small dragonfly trimaran. He was coming from Sweden. I meet him in Portugal, he was bound to the Med. I guess we can call that extensive voyaging

Last year I was interested in a Salona 42 (fast performance cruiser) the owner was a 83 old sailor. He sell it to buy a new Grand Soleil 43, another fast performance cruiser. He cruises alone with its wife that is not much younger than him.

I guess it is a difference in perspective in part due to the lesser options on the American market, but that has certainly nothing to do with age.

Regards

Paulo


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## PCP

wolfenzee said:


> I concede......I now realize it is impossible to defend a boat of my own personal taste against someone who feels that anything other than their personal taste, the "latest, greatest, cutting edge"(what ever that the marketing industry is pushing at the time) is an inferior boat.


This is not about my personal taste. If you go to the Interesting sailboat thread you will find all types of boats including traditional like you own and classic. I have said already that in what regards traditional boats I have a soft spot for them and I even owned one.

This thread is about Fin Keels versus Full keels design and performance. Has nothing to so with the superiority of a given sailboat but with the performance of both keels.

In what regards boat design a full keel is something from the past, not used anymore in boat design because there are more efficient keels available whatever is the boat use. NA don't use them anymore, it is as simple as that.

This does not mean that there is not great designs from the past with full keel that performs very well. But it means that when a NA wants to recreate a classic boat from the past (not a replica) does that using more efficient fin keels and spade rudders. I guess that says it all.

Regards

Paulo


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## hannah2

outbound said:


> Paulo- Your posts here and on the the other thread reflect a difference in the US v. European markets. Here in the rat race of the US there is a niche of sailors who although they have sailed their whole lives can only now in their 60s and 70s go cruising. They want to crusie the San Quins,east coast of US, the Carribean, the South Pacific, the Hebrides, the west coast of europe and north coast of the Med. THEY DON'T WANT TO GO VOYAGING. THEY WANT TO GO CRIUSING. They will make use of those advances that improve the quality of their lives. Comforts and aesethics are just as important to this group as performance. To paraphase Crealock-the "voyage" should equal the joy of the arrival. Have lots of screen on my boat-stll rather read a book.
> The US water tourists don't have the same outlook as the 30 to 40 somethings taking off from europe.


There is a difference between the European and the N. American market. But why? Remember the majority of Europeans cruising are cruising like the Americans are cruising. The Europeans are sailing the Med, north to Sweden, Norway, Great Briton, some go south to the canaries and maybe cross over and continue on into the pacific. Yes we hear of the Europeans going to crazy places in the Artic circle because Europeans love to hear about great adventures and the press reports it. Crealock was right, "voyage should equal the joy of arrival. I think that is true for all most all that go sailing to other places and countries. Europeans love the destination as much as we do.

On the 30 to 40 something outlook. All I can say is that the 30 to 40 age group in Europe has so many more options in sailboats to buy. The affordability of a new boat in Europe is so much better than here in N. America. The 30 to 40 year old in Europe has the same type of income as N. Americans, all the same disavantages like unemployment, the ending recession and far higher taxes. But we see more of them for one major reason a better boat market to get going in. As for the 50,60, even 70 year old market again it is about the same as here. The Majority of that age group in Europe has more income to spend just like here and so they can afford to buy a more expensive and most times a bigger boat. In Europe the options are great, some still buy used boats mostly traditional design and other because of the huge market will go new. Here in America we don't have that new or used market any more.

Yes Americans have a harder time getting use to the European boat. The interior is simple on most of the European boats, the galleys are different and not as seaworthy. On that subject all I can say is if N. America ever gets a new boat market going where boats are being made in the USA they will have simpler interiors than the old days and many will have the European Galley. There is not the rare wood around and the time to do old style joinery without bring the cost up to unreasonable prices. My new boat does not have the same type of interior work as our Mason did. Still nice but I would not have been able to afford the boat if it did have the interior work the Mason had. I like most could live with that as long as it is livable so that I can get the best boat design possible for my needs.

I think it was Oregonian who thought some of us had motives to push European designs. I don't have any motives, I don't sell boats and it's not because I have a new European design on the way. I post on just few threads I find interesting and if I can help someone from N. America who would like to buy a new sailboat instead of an old one then I will point them toward Europe. Why? Because the N. American market is not doing well and there is not a whole lot of options here. I would hope those who are interested in a new boat to sail long distance will open up to new ideas. Why? Because if you do you will have a whole lot more options in getting a very good seaworthy boat available to you. I guess those are my motives.

I will say we are very conservative country, Did I read somewhere that 40% of Americans believe that evolution never took place and in Europe only 4% believe that evolution did not take place. Maybe its the same in boat evolution, there are just going to be more sailors here in N. America no matter what who will not grasp the concept that many new ideas were the evolution of old ideas slowly brought together to give a new and improved product. Certainly the fin keel of the 1970's and 80's is not the same as the fin keel of today.

I would like to say that I have not noticed one attack on some ones older style boat here on this thread. I think posters have pointed out difference in performance but I do not see anyone ripping apart someones boat. This is not a " Is a Hunter a good boat to sail to Greenland in" thread. I know Outbound was interested in a new Boreal like mine but he and the admiral wanted something different in the end. There were things they did not like about the Boreal, the Galley was one. I never took that as an attack on my boat it was his opinion and hey I agree with him I don't like it compared to the Mason 44 galley but we decided we could adapt to the problems. The boat on the whole gave us exactly what we were looking for. By the way if anyone wants to crap on my boat here you are welcome, I want to hear about it, you may know something I don't and I want to know about it so I can solve the problem.

Like " interesting sailboats" this is a very good thread.

Cheers


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## wolfenzee

I agree with you on that, but not everyone sees it that way. Just about every thread eventually breaks down into "my way is the right way and any other way is wrong" often time using generalizations to prove this..I recognize that boating allows for even more diversity than the rest of the world and/or allows you to express this.
A friend of mine who's interests are definitely fin keel, masthead jib, and every modern "improvement" my boat doesn't have continuously finds himself admitting the performance qualities of my boat both power and sail.


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## outbound

Wuffie- I agree with the substance of Hannah's post. There were many features of the Boreal that I found logical and made great sense to me. I think that it is a great boat with outstanding features. I can't crap on it or the boats Paulo talks about. Hannah has not said "this is right and that is wrong". When you contemplate spending much of the rest of you life in a boat your emphatise is altered. Both Hannah and Paulo have said I will have a great boat with excellent perfomance. Both have said at present there are more options with better bang for you buck on the other side of the pond and I think they are right. Hannah has been open and honest. Hannah decided some of the interior features are less important to the quality of their lives than exterior and structural design features.I decided differently. I decided I wanted the best performing boat that included interior features and structural features ( many mentioned in prior posts) that addressed weaknesses in prior boats I've owned or been involved with. I knew I was possibly giving up a percent or two in SOG but gaining multiple things that put my mind at peace and improve the quality of my experience..Believe that would cause us to be more likely to sail the Outbound hard and hopefully far. In the end Hannah's boat added too many variables and new ways of thinking to allow sufficient comfort for my wife and I to make the jump. I pray we both have made the right decision for all of us.I believe I have 95% of the features Paulo exposes and 100% of the features Hannah loved about her Mason. There are boats that have 100% of the features of both but I have yet to find one I can afford and still have something left for the cruiising kitty. I find the interiors of new boats stark and think they will be harder to live in. Others may find them beautiful. I believe it's arrogant to be judgmental about someone else's tastes. But this aspect is important to me as I envision spending countless days on the boat at our various destinations. Silly daily things like having a work shop, doing the laundry,handling the trash,being able to cook a fancy dinner. I always thought the interiors of Hinckleys were beautiful. As far as I know they just make motorboats ( of moden design) now. None of this abborgates the good features of your boat nor the good features of modern bulbed fin keel boats. Wuffie - I hope to cruise with you someday. Perhaps it will open your eyes. I hope to cruise with Hannah perhaps it will open my eyes.Maybe if P cruises with me I'll get "wow this aint so bad and she's fast" Hell, I thought about having Covey Island build me a strip planked schooner (with a moden rig though).There are many ways to seek the horizon. All they are saying is there are more options right now over there then here. They did not meet my needs but may met the needs of others. I expect Phil will be building more boats as I believe there are those with similar views as my own. Know Bob Perry reworked the deck molds to allow a "voyager" version of the 46 and the same design elements have been incorporated in ac 52 version as well. These are new boats. Carl was on to something with the 46- modern design with the liveability of the old. Best of both worlds.
P.S.- wuffie my deal is done. have no financial interest at any level in what any reader of my posts on this subject decide.
Anyone needing proof of evolution can come sit in my waiting room. infectious diseases evolve quicker than our ability to compound antibiotics, tumors mutate and evolve to escape therapy.. G-d moves in mysterious ways. I pray every day but you can't fix dumb


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## GBurton

I have only two things to say and then I'm going to move on (maybe )

1) Evolution has been referenced many times in this thread. Many do not seem to understand the theory of evolution correctly. Evolution does not mean that we are marching to a higher life form (or in this case a higher boat form) Evolution just means things change....yes, not always for the better. 

2) Advertising is meant to inform us. This is also misunderstood by some. Advertising is meant to _persuade_ us, not inform us. Yes, sometimes we are told what we should like. 

I'm going sailing.


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## outbound

evolution is driven by the biologic quotient. It is dispassionate with no right or wrong. those life forms that produce more offspring capable of reproduction have more of their genetic material in the gene pool. GBurton is exactly right. but I hope our kids don't end up with a bunch of crappy boats just because they sell well. (GRIN)


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## CapnBilll

Are we still discussing fin vs full?

I can add some more input. Having recently gone through a storm on a fin keeler, I can say one of the problems I had was difficulty staying on chosen point of sail due to yawing induced by crossing waves. The boat would pivit on the fin, and the rudder was inadequate to counteract this force. 

A longer keel would have been less tiring to steer in this condition, and would have made better way....but I still made it. Other than the yawing the boat didn't do anything else unexpected.

So even though even though fins have their advantages, there are times a full keel has the advantage.


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## hannah2

Hi CapnBill,

Was the fin keel that you sailed a new design or the older style that most of us are use to? Remember the new designs are totally different in rudder, hull, and fin makeup. But I have seen that problem in the fin keels of the 70's 80's 90's and early 00's. Those boats of that era were hard to sail in confused seas and I would have taken some form of a full keel any day over fin. But times have changed and boat design is moving on and I think to a better place.


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## outbound

Hi Hannah- Agree with you but don't fully understand why that is. Your new boat should track like it is on rails once the lee daggerboard is dropped but even boats like mine seem to do just fine n those circumstances. Is it because a high aspect deep rudder develops enough lift? Or because there is enough lateral plane to a single deep balanced fin rudder or two rudders aft? Wuld think the flatter runs to the newer hulls aft would increase "squirelly-ness" but this doesn't seem to be the case. Wonder why.


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## wolfenzee

hannah2 said:


> Hi CapnBill,
> 
> Was the fin keel that you sailed a new design or the older style that most of us are use to? Remember the new designs are totally different in rudder, hull, and fin makeup. But I have seen that problem in the fin keels of the 70's 80's 90's and early 00's. Those boats of that era were hard to sail in confused seas and I would have taken some form of a full keel any day over fin. But times have changed and boat design is moving on and I think to a better place.


If you are going to through all full keels into one category and point out the disadvantages that apply to some. You should be prepared to consider all fin keels. This thread is "fin vs full" not "the worst of the full vs the newest/best of the fin"


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## hannah2

wolfenzee said:


> If you are going to through all full keels into one category and point out the disadvantages that apply to some. You should be prepared to consider all fin keels. This thread is "fin vs full" not "the worst of the full vs the newest/best of the fin"


And why not? I personally would not sail the old style fin keel over any full keeled boat. But I would consider sailing the newer design fin keels to the full keels of yesterday. That being said I like almost all the older full keels and have sailed them to places you can only imagine in your dreams. and would have done it again if that is the choice we made. Again hopefully for the last time, I love full keel boats for cruising long distance but want folks to know that if they are buying a new long distance boat that those new boats have fin keels on the most part and they do a really good job at getting their owners to their destinations in a safe comfortable manner and with better speed than most full keel boats or old fin keeled designs.


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## hannah2

outbound said:


> Hi Hannah- Agree with you but don't fully understand why that is. Your new boat should track like it is on rails once the lee daggerboard is dropped but even boats like mine seem to do just fine n those circumstances. Is it because a high aspect deep rudder develops enough lift? Or because there is enough lateral plane to a single deep balanced fin rudder or two rudders aft? Wuld think the flatter runs to the newer hulls aft would increase "squirelly-ness" but this doesn't seem to be the case. Wonder why.


Hi Outbound, I tried to explain my thoughts on the subject but can not do it as well as Paulo or Jeff so one just needs to go to their posts to explain better than I can. For me I know what I feel when at the helm of a boat most of them cruising boats. The new designs seem to me to drive forward so much better than the old designed fin keel or that matter the old full keel. When I look at the hull design of old fin keels they look closer to the old full keel design than they do the newer designs and I'm sure that has something to do with it. Sorry I can't give you technical details as I'm just a sailor and not a designer.

By the way my wife is very impressed with the Outbound and last night asked me why we didn't look further into them before purchasing our new boat. I had to remind her we wanted the centerboard in aluminum. I'll let you know after we sail her for awhile if we made a mistake but she will let me know before I let you know as she is the supreme boss on our boat.

Cheers


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## outbound

You guys will see places I never will with my draft. I just want to catch up and try to get to some of the places you've been. Just weirded me out the boat tracks better than my old tayana double ender even when surfing. As regards wives had the same experience -she picked the boat off a short menu. Read Jeff and Paulo all the time and learn but don't fully grasp the physics from their posts. Will ask Phil. Don't know of a good discussion of modern design like the old book "Favorable and unfavorable features......" I read eons ago.

Remember -IF a man is all alone in the middle of ocean is he still wrong?
Yes- if he wants to stay married and I do. (GRIN)


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## barefootnavigator

Wow, aluminum, hard chine, with a flippie keel, we may need a new category all together. I must say I am a true traditionalist but that boat is a vision of loveliness.


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## Jeff_H

This whole discussion gets back to what I was trying to say earlier. While it is possible to identify some traits that can be broadly associated with a particular keel type, or any other broad generality for that matter, the reality is that boats work as a system and no matter what the collection of parts, a good design will be a joy to sail no matter what its parts are named (Full, fin, attached, spade, cutter, fractional, masthead etc). and a poor design will be harder and riskier to sail. 

When I look at boats by Atkins or Carl Schumaker, these were designers who knew their stuff and rarely got it wrong. Once you learn to sail these kinds of boats, they can make great sidekicks....regardless of their keel types. 

Jeff


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## PCP

outbound said:


> You guys will see places I never will with my draft. I just want to catch up and try to get to some of the places you've been. Just weirded me out the boat tracks better than my old tayana double ender even when surfing. As regards wives had the same experience -she picked the boat off a short menu. Read Jeff and Paulo all the time and learn but don't fully grasp the physics from their posts. Will ask Phil. Don't know of a good discussion of modern design like the old book "Favorable and unfavorable features......" I read eons ago.
> 
> .... (GRIN)


I try to be as intuitive as I can in what regards any design explanation. You really have to make an effort

Just kidding, but I guess that if we choose s single thing in what regards its major importance in what regards last 20 years of boat design development I would say CAD. And I do not mean for designing but in what regards the immediate possibility of having a pretty good idea of what a given form alteration will produce in a sailboat performance. The programs that NA designers use are very complex and give the possibility to experiment many solutions and predict their effects, something that was a dream before, only possible then with the use of very expensive tank testing and not practical in what regards a big number of alterations.

This provided an huge quantity of information that is on the basis of the fast development that occurred on boat design on the last decades.

Regarding to rudders and fin keels the precision in what regards hydrodynamic studies have conducted to more narrow fin keels and rudders with a small area that work dynamically in a a perfect way. Very rarely a new boat does not perform exactly the way it was predicted and no modification in keel or rudder is required when before it was frequent boats to be perfected along with the production, in the rudder and keel, to give them a better balance.

Regards

Paulo


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## outbound

Play with computers all day at work and always have IT on call waiting.LOL Still, would be delighted if a generally understandable explaination of the physics(the hydrodyamics) of modern designs was available. I can explain the basic physics of fMRI.PET scanning, stereotactic radiosurgery, mEG etc to a reasonably intelligent H.S. grad ( initials after your name does not make you smart and the contrapositive is also true). I'm not a neuroradiologist but understand the basic physics. Boats can't be worse than brains. Wonder if the major players are the matched lift from the foils( keel and rudder), attachment of fluid flow to the canoe body, matched lateral planes of resistance or what. What are these guys looking at and playing with. Something like a vector diagram of the forces with an explanation would be a huge help. Think if general sailing public knew how these boats work acceptance on this side of the pond would be greater. Just saying. Love your thread Paulo, love Jeff's love for any good design done well, and will always go "what if" when I see a Boreal.


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## Thunderchild

This is great information all. I am looking to get my first boat and I am reading and trying to absorb all the great information here.


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## wolfenzee

Thunderchild said:


> This is great information all. I am looking to get my first boat and I am reading and trying to absorb all the great information here.


 The best advice I can give it to charter and/or crew on a wide variety of boats under a wide variety of conditions, this will give you a feel for different boats as well as give you the chance to sail boats you could otherwise not afford.
A boat is an extension of who you are, you don't need to impress anyone except yourself. While some people might prefer old style grace and simplicity others might get off on all the gadgets, gizmos and high tech cutting edge race based designs. So my advice is to decide what YOU like best, what makes YOU feel more comfortable, what fits YOUR uses best...then listen patiently to what everyone else says, nodding politely and gleaning any pertinent information to help you make your final decision. There is no BEST BOAT, there is a huge variety of boats out there, and for a "first boat" I would think you are not looking at a factory fresh 6figure or antique wood.
The economy as it stand will provide some good deals on used boats...one last thing remember, there is no such thing as a free boat.


----------



## PCP

wolfenzee said:


> The best advice I can give it to charter and/or crew on a wide variety of boats under a wide variety of conditions, this will give you a feel for different boats as well as give you the chance to sail boats you could otherwise not afford.
> ....


I subscribe that. With time you will understand what to expect from each type of boat, then you have just to narrower on a good design on the type it suits you better.

Regards

Paulo


----------



## Thunderchild

Wolf and PCP thanks for the great advise. I was looking at something called "Sailtime". I can do bareboat charters on their boats and get to know the ropes as it were. I have been looking for awhile and I have narrowed my choice of manufacturer's to Ericson, Hunter or Catalina. I checked out some Island Packets also but just too pricey for my first boat. I will be looking for a boat between 34 and 38 feet for myself. I will be cruising the Chesapeake Bay for the first couple of years to get to know her and then after that, go out on some longer range voyages. Again thanks for the good advise!


----------



## mergens

BryceGTX said:


> Hello Jeff, I pretty much stopped reading after this paragraph. Damping has nothing to do with inertia. Inertia is related to the square of the distance and the force is a function of acceleration. Damping is related to area and the moment is proportional to distance. The force is a function of velocity.
> 
> Bryce


Inane mix of physics terms


----------



## keforion

Outbound:

If you'd really like to dig into the physics of sailboat design, I'd recommend C A Marchaj's 'Sailing Theory and Practice.' The designs have changed, although not as much as some think -- you can see the same sort of hull design popular today in the 'skimming dishes' and 'sandbaggers' of a century ago. In any event the designs may change but the physics does not.


----------



## outbound

Keforion- thank you for the suggestion. Looked at that book a while back and tasked my poor grey cells. Big difference is I think at present even many monohulls are functioning in semidisplacement or even planing a significant amount of the time. Requirements to maintain attached laminair flow in these settings is somewhat different from my limited understanding of the fluid dynamics. But as you say there is nothing new in the world. One issue to do this with a light dinghy another to a blue water vessel wth significant infill saling in unprotected waters. great suggestion thank you.


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## Reefpoints

I vote full


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## captain jack

Jeff_H said:


> Keels:
> The earliest form of a keel was simply the backbone of the boat extending through the bottom planking. (Like a Viking ship) That works OK with running and reaching sails but when you try to point toward the wind you slip side wards at great speed. As sails and rigs were invented that allowed boats to point toward the wind the keel was extended below the boat either by planking the hull down to a deeper backbone or by adding dead wood (solid timber below the backbone. A planked down keel permitted the space between the planking to be filled with heavy material (originally stone), which served as ballast keeping the boat from heeling. After a while it was discovered that there were advantages to bolting a high-density cast metal ballast to the outside of the deadwood and interior ballast dropped out of fashion.
> 
> Jeff


Very good post. However, the Viking ship, as an example of a keel too shallow to sail upwind, was a bad choice. During the pre-Viking migration age, the Germanic tribes used longships that, to the best of our knowledge, had very shallow keels. The Anglo-saxon ship found at Sutton Hoo is a prime example. Although, in all fairness, due to the state of the find, we can't be sure it didn't have a deeper keel, like a Viking ship. It might have, but no one wants to jump to conclusions without evidence.

A modern replica ( although reduced in size ), of the vessel at Sutton Hoo, is the Sae Wylfing. This vessel will sail to wind at around 60 degrees, I think, but it's better reaching or running.

A deeper keel was the big innovation that the Vikings added to the Germanic longship design. The new, deeper keel allowed them to sail to wind, efficiently. A modern reproduction of the Gokstad ship, the Sigrid Storrada, will do 45 degrees to wind, at 5 mph, in moderate winds.

The abandonment of the longship design, in Northern Europe, was not due to performance issues. The ship that replaced them, the carrack, was easier to defend against the raiding attacks of the longships. The high sides, and even taller forecastle and poop deck, were hard to scale, if you were boarding from a low longship, and made a good platform for throwing rocks and things on the raiders.

This quirk, which made defense more important than performance, set ship design back until the 1800's, really.


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## PCP

captain jack said:


> Very good post. However, the Viking ship, as an example of a keel too shallow to sail upwind, was a bad choice. During the pre-Viking migration age, the Germanic tribes used longships that, to the best of our knowledge, had very shallow keels. The Anglo-saxon ship found at Sutton Hoo is a prime example. Although, in all fairness, due to the state of the find, we can't be sure it didn't have a deeper keel, like a Viking ship. It might have, but no one wants to jump to conclusions without evidence.
> 
> A modern replica ( although reduced in size ), of the vessel at Sutton Hoo, is the Sae Wylfing. This vessel will sail to wind at around 60 degrees, I think, but it's better reaching or running.
> 
> A deeper keel was the big innovation that the Vikings added to the Germanic longship design. The new, deeper keel allowed them to sail to wind, efficiently. A modern reproduction of the Gokstad ship, the Sigrid Storrada, will do 45 degrees to wind, at 5 mph, in moderate winds.
> 
> The abandonment of the longship design, in Northern Europe, was not due to performance issues. The ship that replaced them, the carrack, was easier to defend against the raiding attacks of the longships. The high sides, and even taller forecastle and poop deck, were hard to scale, if you were boarding from a low longship, and made a good platform for throwing rocks and things on the raiders.
> 
> *This quirk, which made defense more important than performance, set ship design back until the 1800's, really*.


Are you saying that sailing boats did not get better in 800 years of evolution? It looks like that and it just does not make any sense. Compared with those 800 years of evolution full keels are very close in performance to fin keels

Regards

Paulo


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## captain jack

Thunderchild said:


> Wolf and PCP thanks for the great advise. I was looking at something called "Sailtime". I can do bareboat charters on their boats and get to know the ropes as it were. I have been looking for awhile and I have narrowed my choice of manufacturer's to Ericson, Hunter or Catalina. I checked out some Island Packets also but just too pricey for my first boat. I will be looking for a boat between 34 and 38 feet for myself. I will be cruising the Chesapeake Bay for the first couple of years to get to know her and then after that, go out on some longer range voyages. Again thanks for the good advise!


If you have never sailed before, at all, you would be better served to learn on something of the 15 foot range. A bigger boat is more stable and less sensitive. If you can handle a smaller boat, a bigger boat is easier. The boat I taught myself on was a tender 10' moth-like dinghy. Later, when I got my holiday 20, it seemed as stable and steady as a rock.

But, if you learn sailing on a cruising yacht, the day you have to sail a smaller boat, like a dingy, will be a shock.


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## captain jack

PCP said:


> Are you saying that sailing boats did not get better in 800 years of evolution? It looks like that and it just does not make any sense. Compared with those 800 years of evolution full keels are very close in performance to fin keels
> 
> Regards
> 
> Paulo


What I am saying is that the Carrack was a huge step back and we didn't develop a sailing vessel as well designed as the Viking longship, again, until around the 1800's. There was a gradual change from the carrack to the brig, but it took a long time. And brigs aren't exactly models of performance.

Yes, there were some, small traditional craft, like the faering, but ship development, as a whole was set back. Imagine how things might have developed differently, if the launch point, for development, had been the longship and not the carrack.

The longship has a lot of features of modern performance sailboats: the narrow entry, the wineglass cross section, the shallow draft ( of the actual hull, not the underwater foil ) at the mid section. If you cut a longship in half, it would resemble some of the new racing boats. Definitely a better platform for sailboat design growth than the carrack.

That's what I am saying.


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## PCP

captain jack said:


> What I am saying is that the Carrack was a huge step back and we didn't develop a sailing vessel as well designed as the Viking longship, again, until around the 1800's. There was a gradual change from the carrack to the brig, but it took a long time. And brigs aren't exactly models of performance.
> 
> Yes, there were some, small traditional craft, like the faering, but ship development, as a whole was set back. Imagine how things might have developed differently, if the launch point, for development, had been the longship and not the carrack.
> 
> The longship has a lot of features of modern performance sailboats: the narrow entry, the wineglass cross section, the shallow draft ( of the actual hull, not the underwater foil ) at the mid section. If you cut a longship in half, it would resemble some of the new racing boats. Definitely a better platform for sailboat design growth than the carrack.
> 
> That's what I am saying.


Yes I understood what you have said but you are mixing things. Carracks were merchant ships. Till 1800 there was a continuous evolution in what regards sailing boats all around the world. You are talking about this type of boat:



The evolution was huge. All these sailingboats are from 1400 to well before 1800:















Regards

Paulo


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## wolfenzee

It's really hard to ask fin or full, for two simple reasons not all boats in either category are the same and not every ones application is the same.


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## mad_machine

I can only say this on the topic. One of our people here spent the winter in the keys aboard. He did tell us of a storm that blew through in the middle of the night. The full keel boats rocked a bit and shrugged it off, the fin keel boats had a rough ride, and some of the centreboarders had a full knockdown

Not a fun way to wake up

I personally prefer a full keel for cruising. I would trade speed for stability when I am just out to have a nice sail. All the extra storage space is nice too.


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## PCP

wolfenzee said:


> It's really hard to ask fin or full, for two simple reasons not all boats in either category are the same and not every ones application is the same.


I thought that Bob Perry thread about improving your boat with a fin keel had changed your opinion about the subject.

The reason why a fin keel,a modified fin keel or even a deeper full keel was not used on old boats, like the ones I posted (or even a centerboard system) was because it was impossible to do so safely with the technologies they had.



mad_machine said:


> ... I would trade speed for stability when I am just out to have a nice sail. All the extra storage space is nice too.


Sailboat stability has not to do with the type of keel used but with boat design as a whole.

Regards

Paulo


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## outbound

Still, there have been modifications applied to full keel boats that improved function such as those using Henry Sheel's work or the keels with a gap in the middle which I recall were done by an englishman who's name escapes me. Unlike the Brewer's bite or cutaway forefoot the basic integrity of the design element was intact. In some respects it's unfortunate improving full keels was not further pursued.One can think of a vessel employing what we now know about attached flow/parasitic drag, tip vortexes but still having an true full keel with attached rudder. With current materials might be easier to build a very strong boat with little deformation from rig loads and reasonably shoal draft given the basic form.


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## captain jack

That is the all around best answer to the OP's question.


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## captain jack

Heck! LOL I was commenting on the poster ho said it's a diffecult question to answer because not all fin or full keels are the same and everyone's needs are different.


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## captain jack

PCP said:


> Yes I understood what you have said but you are mixing things. Carracks were merchant ships. Till 1800 there was a continuous evolution in what regards sailing boats all around the world. You are talking about this type of boat:
> 
> 
> 
> The evolution was huge. All these sailingboats are from 1400 to well before 1800:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Regards
> 
> Paulo


Yes. The first one being the long ship. I agree with you, but none of these vessels perform as well as the longship, and that was my point. Nice pics, by the way.


----------



## captain jack

outbound said:


> Still, there have been modifications applied to full keel boats that improved function such as those using Henry Sheel's work or the keels with a gap in the middle which I recall were done by an englishman who's name escapes me. Unlike the Brewer's bite or cutaway forefoot the basic integrity of the design element was intact. In some respects it's unfortunate improving full keels was not further pursued.One can think of a vessel employing what we now know about attached flow/parasitic drag, tip vortexes but still having an true full keel with attached rudder. With current materials might be easier to build a very strong boat with little deformation from rig loads and reasonably shoal draft given the basic form.


I am going to have to look into those designs. I am interested in learning more about that. If you can remember the name of that Englishman, it would be great.


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## PCP

Jack, the basic hull design of a longboat hull would be great if we could lower the CG with external ballast what obviously could not be done at that time. The boat evolution in what regards sailboats went in the sense of increasing draft as a way to lower CG (the lower bottom of the ships were loaded with stones).

The type of hull of the longboats was not adapted to that, it had a good load capacity but would not go very deep on the water, not allowing the CG to go down substantially.

I agree that the Viking longboats were an amazing design and one that remained at the top for several hundreds of years and that is amazing.

Regards

Paulo


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## captain jack

I will agree with you about that. They certainly could not have supported a modern Bermuda rig, with it's high center of effort. However, even with the tall, square sails which all but one replica use ( it should be noted that there is no evidence for this kind of sail being used and a replica fitted with a tall ship sail, in the late 1800's was the model for this sail ), they have sailed all over the world in longship replicas; a few circumnavigations, too. With a sail that is like those depicted in Viking artwork, like the replica Sigrid Storrada uses, much less ballast is needed than with the tall square sails. I am not actually saying that, if the carrack had not been adopted as the ship to use, we would still be sailing longships. I am saying that sailboat development would probably have advanced much sooner. Where you get, and how long it takes you to get there, depends on where you start.


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## Jeff_H

I think that it is a mistake to think that the DNA of Viking longboats are not a part of modern yacht design. Even though larger working water craft and warships derived from Mediterranean trading vessels and evolved to better use cannons, the basic design concepts pioneered by longboats formed the conceptual basis for smaller working watercraft throughout the rim of the North Sea and was thought to be the inspiration for American whaleboat, and English canoe yawls. 

Jeff


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## PCP

And who said otherwise? We where talking about ships. I only said that from the year 1200 to the year 1800 there was a big evolution in naval architecture and I said it regarding this statement:

*"The abandonment of the longship design... set ship design back until the 1800's, really."*

Regards

Paulo


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## wolfenzee

PCP said:


> I thought that Bob Perry thread about improving your boat with a fin keel had changed your opinion about the subject.
> 
> The reason why a fin keel,a modified fin keel or even a deeper full keel was not used on old boats, like the ones I posted (or even a centerboard system) was because it was impossible to do so safely with the technologies they had.
> 
> Sailboat stability has not to do with the type of keel used but with boat design as a whole.
> 
> Regards
> 
> Paulo


 As I am very happy with the performance of my particular full keel in all weather conditions and all points of sail, none of the tweaks to my design from that would show enough difference to choose them over what I have already. My "antique" design (designed by William Atkin in 1936 based on New England fishing schooners of a much larger size) is not antiquated or inferior simply because of it's vintage.....our culture stresses and is supported by the thought that "new is better and anything else is inferior"...that just is not so. If you find an accurate definition of "*full* keel" my boat would probably not quite match, but it is not a fin keel in any respect.


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## PCP

wolfenzee said:


> As I am very happy with the performance of my particular full keel in all weather conditions and all points of sail, none of the tweaks to my design from that would show enough difference to choose them over what I have already. My "antique" design (designed by William Atkin in 1936 based on New England fishing schooners of a much larger size) is not antiquated or inferior simply because of it's vintage.....our culture stresses and is supported by the thought that "new is better and anything else is inferior"...that just is not so. If you find an accurate definition of "full keel" my boat would probably not quite match, but it is not a fin keel in any respect.


Fact is that as I said I like your boat as a traditional one. I like traditional boats and if I had one I would not have it with a fin keel. That would not be a traditional boat no more, even if it sailed better, it would not sail like a traditional boat and if I had one ( and I had one once) it would be because I like traditional boats not something else.

If I wanted a faster and more modern boat (as I want now) I would not have a copy of a traditional one with a modern underbody, somewhat compromised by the need to follow the general dimensions of the traditional boat (beam and 2 dimensional superior view). I would have prefered a modern design with a hull completely designed for performance without any limitations.

I could have a very modern uncompromised hull in a boat with a traditional flavor, but that is a completely different affair.

Not saying that Bob's approach designed by Jeff is not adequate, I believe some would like a traditional boat with a modern underbody, just saying that I would not like it and I can understand you in what regards that.

Funny that somehow for me it seems not right a traditional boat with a modern underbody but I have nothing against a classic boat with a modern underbody. Maybe because classic boats were all about performance when they were designed or maybe because it is the way I just feel....and reason as nothing to do with it.

That does not mean that I support your idea that yacht design evolution stopped 100 years ago, but that I have pleasure in sailing an old traditional boat even if the performance it is not comparable with the one of a modern sailing boat.

Regards

Paulo


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## outbound

Sorry I can't come up with the NAs name. Bob or Jeff probably know right off. He basically put two keels in series but continued the bottom piece to prevent leakage. I believe the idea was they would work like the "slot" on a sloop improving lift. Motivation was to achieve less draft which I believe is key in many areas of England.


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## mitiempo

His name is Warwick Collins. 




Etap used it on a few models.


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## Faster

outbound said:


> Sorry I can't come up with the NAs name. Bob or Jeff probably know right off. He basically put two keels in series but continued the bottom piece to prevent leakage. I believe the idea was they would work like the "slot" on a sloop improving lift. Motivation was to achieve less draft which I believe is key in many areas of England.


Would you be thinking of Warwick Collins and his 'tandem keel'?

The Universal Hull by Warwick Collins | My Wooden Boat of the Week

EDIT... huh... Brian beat me to it!


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## wolfenzee

Thing is about seeking a "faster boat", it doesn't take much to get my boat to hull speed, a "faster" boat might be able to accomplish that with less sail area..or maybe not. As far as performance to windward, it does very well. Basically it is a 75 year old design, which with the modest rig tweaks over the years has become a high performance boat. I am a cruising sailor, so simplicity is stressed, I don't like spinnakers but have enough canvas to trough up to give me great down wind performance, without the hassles.


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## captain jack

Thanks for the info, guys. I am going to go do a little research.


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## Jeff_H

PCP said:


> And who said otherwise? We where talking about ships. I only said that from the year 1200 to the year 1800 there was a big evolution in naval architecture and I said it regarding this statement:
> 
> *"The abandonment of the longship design... set ship design back until the 1800's, really."*
> 
> Regards
> 
> Paulo


As I read the thread I think you and I were basically in agreement. I was commenting on captnjack's lament on the long boat.

Jeff


----------



## PCP

captain jack said:


> Thanks for the info, guys. I am going to go do a little research.


If you like naval history and boat design than we share a common interest.

The ship development since the middle ages has to do with several components: Seaworthiness, Loading capacity, sail performance and defense requirements.

You are right in saying that the defense and loading requirements are many times contradictory with sail performance but those two requirements or the relative weight in the compromise were not common to all designs. On a given time there were always different compromises depending on the use that was given to the boat and there were always use for good and fast performance ships that corresponded to the best it could be made in that time.

Regarding mainstream, I mean a boat that could satisfy all those requirements that I talked about was the Galeão (Galeon) also called Nau, developed by the Portuguese and in lesser measure by the Spanish during the XVI century.
Here a primitive example:



The boat was designed to be very seaworthy, to have a big carrying capacity and to be able to defend itself. It is a evolution of a Carrack and the first ones were designed specially for the first voyage to India under the requirements set by the most experienced and better sailor of that era, Bartolomeu Dias:

This is a replica of that boat:



There were extensive studies carried take as model a late exemplar (1606) in what regards intact stability and the results were incredible:

http://nautarch.tamu.edu/shiplab/00-pdf/Fonseca, Santos and Castro 2005 IMAM.pdf

Of course this was a Portuguese ship and for the calculations of CG wine weight was also took into consideration:

"Regarding the *wine*, the average consumption was 0.5 l a day,
resulting in a weight of *40 t*"

They would go and take all the risks, but not without wine

That strangely rounded hull and high free-boards allow it a reserve stability that we can only call modern and superior to the one of more modern and fast posterior ships.



And allowed them to carry an huge amount of sail (drawing made at that time):



Regards

Paulo


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## desert rat

Woah. Forty two gunports, the Flying Cloud had only one long nine on a swivel mounted either for or aft.


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## captain jack

Interesting read. It would, also, be interesting to see performance qualities for this vessel. Where do you get this kind of information? I would be interested in further reading of this type. Thanks for the informative post.


----------



## bobperry

Well said Wolfy.


----------



## PCP

captain jack said:


> Interesting read. It would, also, be interesting to see performance qualities for this vessel. Where do you get this kind of information? I would be interested in further reading of this type. Thanks for the informative post.


A bit everywhere, there are some interesting books in Portuguese, some in French and Dutch and some in Swedish.

Do you know Björn Landström?

If not just buy these old books and I promise you a fascinating read .

The Ship: An Illustrated History by Björn Landström - Reviews, Discussion, Bookclubs, Lists

Bold voyages and great explorers;: A history of discovery and exploration from the expedition to the land of Punt in 1493 B.C. to the discovery of the ... A.D. in words and pictures A Windfall book: Amazon.co.uk: Bjorn Landstrom: [email protected]@[email protected]@http://ecx.images-amazon.com/images/I/[email protected]@[email protected]@51apeQEQP-L

and this is a true classic:

Amazon.com: Architectura Navalis Mercatoria: The Classic of Eighteenth-Century Naval Architecture (Dover Maritime) (9780486451558): Fredrik Henrik af Chapman: [email protected]@[email protected]@http://ecx.images-amazon.com/images/I/[email protected]@[email protected]@51RV7ATS5CL

The Sailing Frigate: A History in Ship Models: Robert Gardiner: 9781848321601: Amazon.com: [email protected]@[email protected]@http://ecx.images-amazon.com/images/I/[email protected]@[email protected]@51vSE-Ju5oL

Regarding speed of old boats some are a surprise: The Caravela (the one that is one the front page on the book of exploration) was not a merchant boat but an explorer boat, so it was fast and could sail quite well against the wind.

Look at this movis with a XV century replica compare its speed with the speed of the modern boats around. Take notice that they were accused of not having the sails as big on that replica as on the original boats and even so...they can sail pretty well and downwind was its weakest point of sail of that boat.


----------



## mad_machine

desert rat said:


> Woah. Forty two gunports, the Flying Cloud had only one long nine on a swivel mounted either for or aft.


The flying cloud was a clipper ship that could outrun most pirates, not to mention she was one of the last, so most of the wars done with sail were long past.

It's a shame that she eventually got scrapped. Atlantic City should have taken better care of her


----------



## outbound

fascinating links about Warwick Collins. that's thinking outside the box. thank you gentlemen. ? hasn't Etap folded shop in Belgium. if so too bad a truly unsinkable boat seems like such a good idea.


----------



## Classic30

mad_machine said:


> The flying cloud was a clipper ship that could outrun most pirates, not to mention she was one of the last, so most of the wars done with sail were long past.


Fast was quite right. According to the wikipedia entry, the maximum logged speed for _Cutty Sark_ was 17.5 knots - with an average speed over six days on one London to Melbourne trip of a little over 15kts! 

Nothing slow about that..


----------



## mitiempo

Hartley18 said:


> Fast was quite right. According to the wikipedia entry, the maximum logged speed for _Cutty Sark_ was 17.5 knots - with an average speed over six days on one London to Melbourne trip of a little over 15kts!
> 
> Nothing slow about that..


True, but with a waterline approaching 200' that is not quite displacement hull speed. (1.34 x sq root of waterline length)


----------



## Classic30

mitiempo said:


> True, but with a waterline approaching 200' that is not quite displacement hull speed. (1.34 x sq root of waterline length)


Given that a Clipper doing hull speed would likely break in half... perhaps that formula doesn't apply. It'd look bloody spectacular though!!


----------



## mitiempo

She wasn't surfing so it would have to apply. Length is the easiest way to increase speed. Large ships today travel way under hull speed economically. Hull speed of a Panamax ship surpasses 40 knots.


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## PCP

mitiempo said:


> She wasn't surfing so it would have to apply. Length is the easiest way to increase speed. Large ships today travel way under hull speed economically. Hull speed of a Panamax ship surpasses 40 knots.


That is not different with us. If the hull speed is 8k the economic engine speed would be about 4.5, 5K.

Regards

Paulo


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## wolfenzee

My theoretical hull speed is 6.75kt, the most efficient speed of my engine (Vetus M4.15 33hp diesel) is 2000rpm. At 2000rpm w/16x9 prop I am doing 6.5kt using <0.4gph
6.5kt seems to be the "magic number" for my boat, it doesn't take much to get the boat to 6.5 under sail either.


----------



## outbound

then again there's power sailing. always seem to pick up a knot or two that way. still best to have a easily driven boat and keep the damn thing off. ( grin)


----------



## wolfenzee

outbound said:


> then again there's power sailing. always seem to pick up a knot or two that way. still best to have a easily driven boat and keep the damn thing off. ( grin)


 At 2200rpm, my stern is squatted down in the water, I am using alot more fuel and gaining a 1/2kt over 2000rpm. I am going over the boats hull speed and am at it's physical limit. What you call "power sailing would not gain my more than a 1/2kt. My boat is what used to be called an auxiliary, back when engines were an auxiliary form of propulsion. Now adays it seems people use their sails for auxiliary and/or entertainment and their engines to get the boat back to the dock in time. If you need to go faster than sails will allow then maybe you should trade your boat in on a "stink pot". If a knot or too stresses you out you need to spend more time sailing...put yourself in a position where you don't have to be any where or back from anywhere at any time special.
To those of you that this does not apply, please don't be offended, because it was not directed at you. To those of you that this does apply, don't get offended either, just learn to chill.


----------



## outbound

Wolfie - I once totally ruin the salt water cooling system of a earlier boat by sailing on and off my mooring and anchoring out when cruising. Think I had zero engine hours that season. When it was time pull the boat for the winter found out mussels and other critters had taken up residence in the cooling system. Ended up having to replace most of it. Was embarressing getting towed in to be pulled. Oh well. Still, think the engine is the aid of the sails although the last few boats have been documented as oil screws. See too many folks rocking and rolling liberating hydrocarbons unneccessarily when they could leave a sail up and have a nicer ride,burn less fuel and have the pleasure of a sail up. Only time my main comes down is when I'm running in a significant breeze or singling on a day sail and too lazy to pull it up. Agree it's a problem with narrow sterns. They do tend to squat under power. Was trying to encourage more sailing. Sorry you took it differently.


----------



## outbound

Wolfie- I apologize re read yur post.Maybe there is some confusion. By power sailing I mean leaving at least the main up when the engine is on.


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## RickWestlake

wolfenzee said:


> At 2200rpm, my stern is squatted down in the water, I am using alot more fuel and gaining a 1/2kt over 2000rpm. I am going over the boats hull speed and am at it's physical limit. What you call "power sailing would not gain my more than a 1/2kt. My boat is what used to be called an auxiliary, back when engines were an auxiliary form of propulsion. Now adays it seems people use their sails for auxiliary and/or entertainment and their engines to get the boat back to the dock in time. If you need to go faster than sails will allow then maybe you should trade your boat in on a "stink pot". If a knot or too stresses you out you need to spend more time sailing...put yourself in a position where you don't have to be any where or back from anywhere at any time special.
> To those of you that this does not apply, please don't be offended, because it was not directed at you. To those of you that this does apply, don't get offended either, just learn to chill.


And for those of us with MacGregor motorsailers, like my old 26X? 

The best of both worlds ... and the worst.:laugher


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## wolfenzee

Even living at the dock and not taking my boat out I still exercise my engine.

The MacGregors with enough power can get up and plane to get you back to the marina in time so you don't miss cocktail hour. As much as I dislike them, I have noticed one thing about MacGregors.....the owners do tend to use them a lot more, and that what it's all about right.
It is possible for me to get my boat over 20kts....but that would involve putting it on a container ship.


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## outbound

Yup- for the last 25+ years take her out for a run now and again. Believe the diesel gets more "exercise" when run under a load then on the mooring or slip. Live and learn.


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## wolfenzee

Running it under load at the slip occasionally is still better than just letting it sit, and yes I do take it out occasionally.


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## killarney_sailor

Paulo, your last picture looks like a boat designed to beat a rating system weighted against LOA.


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## PCP

killarney_sailor said:


> Paulo, your last picture looks like a boat designed to beat a rating system weighted against LOA.


Sorry Killarney I don't know what you are talking about. The last boats I posted where historical boats.

Regards

Paulo


----------



## RickWestlake

wolfenzee said:


> Even living at the dock and not taking my boat out I still exercise my engine.
> 
> The MacGregors with enough power can get up and plane to get you back to the marina in time so you don't miss cocktail hour. As much as I dislike them, I have noticed one thing about MacGregors.....the owners do tend to use them a lot more, and that what it's all about right.
> It is possible for me to get my boat over 20kts....but that would involve putting it on a container ship.


I described my Mac 26X, Bossa Nova, as a 26-foot, sleep-aboard sailing dinghy, that can also serve as a funny-shaped travel trailer. It's a very good first boat, for someone who hasn't decided between sailing or power-boating, or who wants to take it on a camping vacation to some big lake or bay, or other sheltered waters; and I know a few people who have taken their MacGregors to the Bahamas, and had a great trip of it.

But you can only do so much with a Mac.

I don't regret putting my Mac up for sale and buying my current Bristol 29.9, even if I'm paying several times as much to keep Halcyon in a slip as I was paying to keep Bossa Nova on her trailer at the same marina.


----------



## ashmun

There are also cut away and modified keels. Much of the choice depends on your sailing preferences: fast vs comfortable (sea kindly); deep water ocean cruising (deeper keel) vs Bahamas bank or wanting to pull into shallow harbors (shoal keel); etc. As mentioned above, having the rudder be shorter than the keel and protected (hung or skeg) is import for cruising. We have a heavy boat with a 5.5’ draft. She’s not fast but she’s comfortable (aka civilized) and sea worthy. With the 5.5’ draft there are a number of hurricane holes here in the Bahamas that I can not get into and harbors that I have to wait for high tide to enter. I’m ok with these trade offs. 

As all the sailboat cruising and boat buying books would say, there are always trade-off when aquiring a boat. 

Julia 
S/V Esprit
Mariner 39 (NH built, cruising version)


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## wolfenzee

Everything is a compromise of some sort or another...it's just more obvious in boats


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## PCP

outbound said:


> Still, there have been modifications applied to full keel boats that improved function such as those using Henry Sheel's work or the keels with a gap in the middle which I recall were done by an englishman who's name escapes me. ..


 the Scheel keel that I know is a kind of previous bulbed keel but with a lot of drag.

I guess you are talking about tandem keels? Those are a lot more interesting specially in what regards low draft solutions even if they have been used (without much success) even in top race boats.













Regards

Paulo


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## bobperry

The gap distance between the two fins is critical Look at it on the AC boat. Most more mundane boats do not have the bulb length to accomodate the required gap distance.


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## PCP

Yes, I know but has some major Na have been using them (I believe Farr had designed one for the shoal version of the Bavaria vision) I believe they can design them in an effective way otherwise they would not be using them. I am quite sure they design them using CFD.


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## bobperry

"I believe they can design them in an effective way otherwise they would not be using them."

What a novel thought. I wonder how many design features have been tried over the years that have proven less than effective but initiated with that same optimism? The "split keel" has been around for quite a long time.

Maybe in time it will join some other "breakthrough" keels like theScheel keel, Reijo Salminen wing keel, eliptical planform keels, to name three.


----------



## PCP

bobperry said:


> "I believe they can design them in an effective way otherwise they would not be using them."
> 
> What a novel thought. I wonder how many design features have been tried over the years that have proven less than effective but initiated with that same optimism? The "split keel" has been around for quite a long time.
> 
> ....


Sorry, I guess I was not been clear. They are around as you say for a long time, from the time CFD studies were not the norm to study keel, hull and rudder efficiency, but things were done by try and error, experience and a good eye.

They survived till today were they are designed not by trial and error but by seeing their comparative performance with other types of keels in CFD studies. If they are still used by major NAs it is because they are a valid alternative to other options, specially in what regards low draft options.

For instance, Mortain&Mavrikios, the designers of the line of Harmony, Etap, Lockwind, Passoa, Nautitech Feeling and some Dufour said about tandem keels regarding their use on the Harmony:

*"Those looking for small draughts will be delighted to know that cast-iron tandem keels &#8230;offer almost the same sail stiffness and the same ability to go close winded as lead keels with far deeper bulbs".*

http://www.mortain-mavrikios.com/MMC Brochure.pdf

And Etap said some years ago regarding the use of tandem Keels on the Etap 30i:

*"After thorough investigation and numerous tests, ETAP Yachting N.V. is pleased to introduce its ETAP tandem keel. The most important advantages of this keel are the excellent sailing qualities at a considerably reduced draft. This new design is the result of a co-operation with the architects' bureau Mortain-Mavrikios.

The two most important features to reduce drift, are the size of the lateral plan and its efficiency. The efficiency is defined by the proportion between the depth of the keel and the length. Also a wing section is a classic aid to improve the efficiency.

For a strong reduction of the draft neither a wing keel or a bulb keel were sufficient. The solution was found in placing two shorter keels behind one another, linked by a wing-bulb profile : the ETAP tandem keel.

The ETAP tandem keel gives a better aspect ratio, thus generating more lift. 
In addition to increased stability, the wing-bulb also provides better hydrodynamic characteristics. "*

Tandem keels are also used by J&J yacht design in several Bavarias.

http://greenlinehybrid.com/J-and-J-design

Regards

Paulo


----------



## bobperry

Don't see anything about CFD Paulo. How are you certain CFD was used? Can you provide a CFD study that has been published? I'd like to see that for my own education. I wouldn't make the automatic assumption that CFD is being used for every new keel you see from a major design office.

I understand the theory behind the tandem keel. As I said it is far from a new keel geometry. I don't doubt that it works, to some degree. But the real appeal may be more for marketing. Seems like you bought it.


----------



## PCP

bobperry said:


> Don't see anything about CFD Paulo. How are you certain CFD was used? Can you provide a CFD study that has been published? I'd like to see that for my own education. I wouldn't make the automatic assumption that CFD is being used for every new keel you see from a major design office.
> 
> I understand the theory behind the tandem keel. As I said it is far from a new keel geometry. I don't doubt that it works, to some degree. But the real appeal may be more for marketing. Seems like you bought it.


I don't know of any major NA cabinet that does not use CFD in what regards hull, keel and rudder design.

I am not defending tandem keels against other solutions for swallow draft. I am only saying that it is still a contemporary solution in a sense that it continues to be a valuable option.

Personally I think that the best contemporary solution for a shallow draft are swinging keels. Those are the only ones that manage the miracle of offering a similar tracking upwind, a slightly lower weight for the same RM at the cost of a slightly bigger draft without having a big intrusion on the interior habitability. The only real problem is that they increase the boat price and need some maintenance.

Regards

Paulo


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## bobperry

Paulo:
I'll have to defer to your superior knowledge in the area of yacht design and yacht design offices. I have not been at this very long. You obviosly have far more depth and bredth to your design office experience than I have. I can only hope to one day have as much knowledge of yacht design as you think you have.

Here are a couple of small projects of mine. I'd love to see some of yours.

I am in full agreement with you that swing keels are the optimal solution for shoal draft. I am very lucky in that I live where the water is very deep so shoal draft is not a concern of mine. Although I have designed one or two boats where draft was a major consideration.


----------



## PCP

bobperry said:


> Paulo:
> I'll have to defer to your superior knowledge in the area of yacht design and yacht design offices. I have not been at this very long. You obviosly have far more depth and bredth to your design office experience than I have. I can only hope to one day have as much knowledge of yacht design as you think you have.
> 
> Here are a couple of small projects of mine. I'd love to see some of yours.
> 
> I am in full agreement with you that swing keels are the optimal solution for shoal draft. I am very lucky in that I live where the water is very deep so shoal draft is not a concern of mine. Although I have designed one or two boats where draft was a major consideration.


I don'y understand your attitude. I am not a yacht designer and I never have pretended to be. That does not make less true that today all major NA cabinets use CFD in what regards designing hulls, keels or rudders. Many advertise so on their web sites and others even publish some computer prints of the studies. It is only a complex computer program that accesses the efficiency of what has been drawn and contributes to improve the design.

Regards

Paulo


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## bobperry

Oh come on Paulo. 
Me? An attitude? I'm not sure what you mean.


----------



## Jeff_H

PCP said:


> I don'y understand your attitude. I am not a yacht designer and I never have pretended to be. That does not make less true that today all major NA cabinets use CFD in what regards designing hulls, keels or rudders. Many advertise so on their web sites and others even publish some computer prints of the studies. It is only a complex computer program that accesses the efficiency of what has been drawn and contributes to improve the design.
> 
> Regards
> 
> Paulo


Paulo, I am not sure that your assumptions are right. I attend a lot of presentations on the development of yacht design software and how it is being used. Clearly CFD is out there and being used on specfic projects by the high visibility high performance shops. But for the most part, what seems to be way more common in design offices are a battery of VPP's (velocity prediction programs) that are based on historical data and prior CFD and towing tank studies. These VPP's are pretty good but they do not analyze down to a level of detail which would validate the performance of a particular choice of keel profile, keel section, or keel layout.

The better of these programs produce quasi CFD data and the kinds of graphics that replicate what you would expect out of a full blown CFD analysis, but these programs do not appear to be at the fine grain level that would be needed to analyze whether a specific tandem keel worked effectively or not.

This is not to say that RANS and CFD analysis is never performed. I think that really high budget projects get that level of attention. Farr's office showed amazing graphics from their analysis of the new Volvo boats.

I am talking with Quantum about doing a paper exploring the trade off between sail area and sail shaping for cruising boats (i.e. more powerful sections vs. larger sail area) and in the course of the preliminary conversation, it was suggested that ideally we should use the VPP for a specific design, including the drag, leeway, and stability characteristics of a real hull and rig.

The designer at Quantum and I spoke to one of the partners at Farr about the likelihood of getting basic data on one of thier newer production designs, and while it was clear that Farr ran moderately sophisticated performance analysis on all of their designs, it was not clear that it was run on a fine grained enough level to allow a precise enough computer simulation for the sail study.

As recently as only two years ago, there was a paper presented on a study to validate a CFD analysis of flows around a keel. It was one of the first times that they were able to instriment a full sized keel in action to measure the points at which laminar flow became turbulent. They found that there was almost no steady state laminar flow, and that the flow even in calm water was discontinuous, shredding in much the same way that spinnakers have discontinuous flow. It largely invalidated the CFD which assumed way more continuous flow than existed, and it was only once factors were added for discountinuity that the CFD could be validated.

So, while I do not want to talk for Bob, and I do not want to be dimissive of what you are saying, my sense of this is that CFD, especially for keels is still in its infancy, and that while better design firms have access to CFD for their higher budget projects, it is not in general use and perhaps fine level analysis not accessible enough to acertain that a tandem keel really does work as advertised.

Respectfully,
Jeff


----------



## Cruisingdad

I hope this is not considered a hijack, but since i know nothing about sailing or cruising, just wanted to ask: why would anyone choose a racer for a cruiser? 

Just askin'. 

Brian


----------



## PCP

Jeff_H said:


> Paulo, I am not sure that your assumptions are right. I attend a lot of presentations on the development of yacht design software and how it is being used. Clearly CFD is out there and being used on specfic projects by the high visibility high performance shops. But for the most part, what seems to be way more common in design offices are a battery of VPP's (velocity prediction programs) that are based on historical data and prior CFD and towing tank studies. These VPP's are pretty good but they do not analyze down to a level of detail which would validate the performance of a particular choice of keel profile, keel section, or keel layout.
> 
> The better of these programs produce quasi CFD data and the kinds of graphics that replicate what you would expect out of a full blown CFD analysis, but these programs do not appear to be at the fine grain level that would be needed to analyze whether a specific tandem keel worked effectively or not.
> 
> This is not to say that RANS and CFD analysis is never performed. I think that really high budget projects get that level of attention. Farr's office showed amazing graphics from their analysis of the new Volvo boats.
> 
> I am talking with Quantum about doing a paper exploring the trade off between sail area and sail shaping for cruising boats (i.e. more powerful sections vs. larger sail area) and in the course of the preliminary conversation, it was suggested that ideally we should use the VPP for a specific design, including the drag, leeway, and stability characteristics of a real hull and rig.
> 
> The designer at Quantum and I spoke to one of the partners at Farr about the likelihood of getting basic data on one of thier newer production designs, and while it was clear that Farr ran moderately sophisticated performance analysis on all of their designs, it was not clear that it was run on a fine grained enough level to allow a precise enough computer simulation for the sail study.
> 
> As recently as only two years ago, there was a paper presented on a study to validate a CFD analysis of flows around a keel. It was one of the first times that they were able to instriment a full sized keel in action to measure the points at which laminar flow became turbulent. They found that there was almost no steady state laminar flow, and that the flow even in calm water was discontinuous, shredding in much the same way that spinnakers have discontinuous flow. It largely invalidated the CFD which assumed way more continuous flow than existed, and it was only once factors were added for discountinuity that the CFD could be validated.
> 
> So, while I do not want to talk for Bob, and I do not want to be dimissive of what you are saying, my sense of this is that CFD, especially for keels is still in its infancy, and that while better design firms have access to CFD for their higher budget projects, it is not in general use and perhaps fine level analysis not accessible enough to acertain that a tandem keel really does work as advertised.
> 
> Respectfully,
> Jeff


I did not said all NA, I had said major NA firms use CFD to help designing boats. As you have pointed out Farr use it as other major Na firms and even some minor ones. Look at these computer printouts from Ker. The first one refers to the final hull for the Sydney GTS 43, designed with the help of CFD, the second one is a beautiful study on a keel and ruder flow.

You can read on the site about the CFD they use (Numeca).

http://www.kerdesign.com/Technology.html





Some advertise that on their site, others not. Have a look at Berret/Racoupeu (the designers of Allures among other sailingboats):

As part of our research and development efforts, we made the deliberate choice, some time ago, to incorporate totally digital calculation and analysis procedures.

As genuine decision-making tools, these different digital simulation programs enable us to confirm our design ideas in a flexible and efficient manner and at an acceptable price. In contrast, to achieve comparable accuracy, experimental processes such as towing tank tests, wind tunnel testing or mechanical trials are significantly more laborious and costly, less "state-of-the-art" and ill-suited to systematic use.

*Digital tools enable us to optimise hull shapes, sail plans, appendages such as keels, and rudders for example, and to predict their performance based on outdoor conditions such as the wind, its strength, the direction its blowing from and the state of the sea. All of our yachts systematically undergo these simulation steps to guarantee optimized performance and handling.* Structure is high on the agenda too, using finite element method (FEM) calculations. This equipment is systematically incorporated into our design procedure, for all of our creations. Over the years, thanks to our experience, we've developed and optimized their use.







http://www.berret-racoupeau.com/recherche_uk.php

Regards

Paulo


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## Classic30

Jeff_H said:


> ........
> I am talking with Quantum about doing a paper exploring the trade off between sail area and sail shaping for cruising boats (i.e. more powerful sections vs. larger sail area)....


 

Having recently forked out $$ for a headsail that after 4 re-cuts we can't get driving properly - that's got MY interest, Jeff! 

Care to add anything else - or start a separate thread on this??

Cheers, C


----------



## bobperry

Paulo those are lovely photos you downloaded from the internet. I'm not sure what they have to do with the tandem keel though. I see no mention of the tandem keel in any of that downloaded material.

I have no issue with CFD at all. It's a wonderful tool when used correctly. My original question had to do with why was Paulo so certain CFD had been used to design those tandem keels?


----------



## PCP

bobperry said:


> Paulo those are lovely photos you downloaded from the internet. I'm not sure what they have to do with the tandem keel though. I see no mention of the tandem keel in any of that downloaded material.
> 
> I have no issue with CFD at all. It's a wonderful tool when used correctly. My original question had to do with why was Paulo so certain CFD had been used to design those tandem keels?


Bob, I don't know if the several modern tandem keels designed recently by some major NAs where designed used CFD, a speed prediction program or tank testing.



bobperry said:


> ... I wouldn't make the automatic assumption that CFD is being used for every new keel you see from a major design office....


Not all NA are using yet CFD or based speed prediction complex programs but big NA offices are (in general terms) and some smaller ones too. Those images that I downloaded from the internet were from the sites of two Naval Design offices : Ker and Berret/Racoupeau.

But I would find hard to believe major NAs making statements like these ones without knowing about what they are talking about:

*"Those looking for small draughts will be delighted to know that cast-iron tandem keels &#8230;offer almost the same sail stiffness and the same ability to go close winded as lead keels with far deeper bulbs"*
Mortain/Mavrikios

*"The tandem keel is an alternative to the twin keel, it increases lift while reducing drag "*
Defline

Both have recently worked and used tandem keels on their sailboats designs. Do you think they don't know what they are talking about?

Both firms are well respected and credible, we are not talking about a boat manufacturer making publicity, they work with several different types of keels. I don't think they are making these statements without knowledge. Sure, there are several ways of testing to acquire that knowledge, from tank testing to testing in real size, but CFD or a based speed prediction complex program is the more inexpensive way.

Regards

Paulo


----------



## bobperry

Fine Paulo. That's exactly what I thought. Thanks for clarifying that.


----------



## Jeff_H

Paulo,

I would like to comment that very often it sounds like you and I are disagreeing with each other when in fact, we seem to have similar opinions. 
I suggest that this conversation is one of those cases.

For example, we agree that many of the larger yacht design firms do employ CFD. We seem to agree that the use of CFD is not always the case. It sounds like we agree that the forms of CFD that are used vary from extremely sophisticated versions, capable of reasonably fine grained analysis, to pretty course versions which are good at evaluating general data trends but not providing highly accurate quantitative data.

I should also note that I am very aprpeciative of your posts which talk about the broad range of 'experimental' or 'non-traditional' design taking place in Europe. I use the terms 'experimental' or 'non-traditional' only in reference to what is happening in the U.S. which, for better or worse, tends to be more conservative.

Where we sometimes go off the rails is in how we interpret what we read. For example: _"Digital tools enable us to optimise hull shapes, sail plans, appendages such as keels, and rudders for example, and to predict their performance based on outdoor conditions such as the wind, its strength, the direction its blowing from and the state of the sea. All of our yachts systematically undergo these simulation steps to guarantee optimized performance and handling. Structure is high on the agenda too, using finite element method (FEM) calculations. This equipment is systematically incorporated into our design procedure, for all of our creations." _

I think that statement is one that all of us come to general agreement on. But that statement does not describe the specific digital tools being used, and does not specify CFD. So while CFD may be used, it does not necessarily mean that Berret/Racoupeu does use CFD, or how they use CFD, or whether they analyze their keels and rudders using CFD.

This is similar to the two Mortain/Mavrikios statements:

"Those looking for small draughts will be delighted to know that cast-iron tandem keels &#8230;offer almost the same sail stiffness and the same ability to go close winded as lead keels with far deeper bulbs"

"The tandem keel is an alternative to the twin keel, it increases lift while reducing drag "

I think that we could agree that there is a possibility that these statements could be true. But where you and I, and perhaps Bob might not agree is the pieces of those statements which are missing.

If we look at the first statement, my interpretation is that it says two things, a that cast-iron tandem keels can offer almost as much stability as a deeper lead keel with a bulb, and that cast-iron tandem keels can point as high (i.e. close winded) as a deeper lead keel with a bulb. Properly designed, both may be true. And it does not take CFD to prove that statement to be true.

What that statement does not say is that cast-iron tandem keels designed to offer the same stability and pointing ability offer the same VMG as a deeper lead keel with a bulb.

And my sense is that the cast-iron tandem keels offering the same stability and apparent wind angle, cannot offer the same VMG, because by its very nature being cast iron, and shallower, the volume of the tandem keel needs to be greater than the volume of the deeper straight fin with bulb, and therefore there is more wetted surface, and therefore there is more drag, and therefore there is less speed for a given sail area, even if there is equal stability to carry that sail area.

The second statement can be viewed similarly. To me that statement says that properly designed a tandem keel offers greater lift relative to drag as compared to a twin keel. It does not take CFD to find agreement in that statement.

I assume we are in agreement that when you look at the drag of any foil and bulb keel, there are a number of drag inducing elements. Wetted surface certainly is the big one at slower speeds. But as speeds increase, induced drag becomes more significant. And in that equation if we assume equal foil lengths and both keel types operating in undisturbed water, the bulbs on both acting effectively as end plates, then we can assume for the moment that for equal lift, the foils generate equal drag.

But there would be very different amounts of drag for the bulbs. The twin keel would have two smaller bulbs than the tandem, and the properties of those two bulbes mean that the tandem keel has two leading edges, two trailing edges, and more surface area, (since proportion of internal volume to surface area increases with size).

And if tandem keels could have inherently less drag for an equal lift, then its possible to partially use some of that difference to increase the lift on the tandem keel so that it offers more lift for less drag.

In other words, without CFD its pretty easy to see that this claim could be true. On the other hand, there was an assumption that the downstream keel foil of the tandem keel produces the same lift as the twin keels, and it is here that this statement may go off the rails. I do not believe that to always be the case, and it would be next to impossible to make that kind of universal statement since the reality of this is so dependent on the specific design, and conditions.

What that statement cannot address are issues that cannot be defined in broad terms and for which we have no tools to adequately evaluate universally. For example, one advantage of a twin keel is that as it heels, the leeward keel becomes more perpendicular to the side force, and in flat water, the windward one reduces drag as it is lifted out of the water. that should offer some advantages to the tandem keel.

But in waves, the collisions of the waves with the windward foil would offer a large non-steady state drag which will vary with wave size, steepness and frequency, and which could return the drag advatage to the immersed tandem keel.

It is for those types of reasons that perhaps I sometimes view these kinds of designer statements with perhaps more skepticism than your comments appear to reflect.(And while I don't want to speak for Bob, I speculate that he may also come at this with a similar and definitely far more experienced based skepticism.)

Respectfully,
Jeff


----------



## bobperry

I asked a very simple question of Paulo when he claimed the tandem keels were designed using CFD studies. "How do you know that CFD was used to design those tandem keels?"
Getting a succinct answer was anything but easy.

My point was this:
The tandem keel (if we are going to call it that) Has been around for about 20 years now. It was tried on an AC boat with some success but other AC boats did not use it. There's probably a very good reason for that. In my consultations and work with Laurie Davidson and his AC effort I was exposed to some experimental AC design ideas. Most, the "hula" for example, were abandoned along with the tandem keel and the forward rudder. And certainly by any criteria the AC boats had restricted draft. It was a rule. One of the things they found with the tandem keel is the distance between fins was critical. The aft fin is operating in the "bad air" of the forward fin, i.e. turbulence off the forward fin and an increased angle of attack. Think about racing and trying to sail straight up the stern of the boat ahead. It NEVER works. So in order to get some clean flow of water with a reasonable angle of attack on the aft fin the two fins have to be separated. The basic rule, as I recall, for the aft fin to have "clean water" was 7 times the tip chord of the fin. You can clearly see that in the photo Paulo posted of the AC tandem keel.

But in the new, tandem keels the two fins are squeezed together with barely one chord length separating the two fins. With the two fins this close together I can't See how the aft fin can have any clean flow over it. It has to be operating in turbulence and with an increased angle of attack, i.e. increased drag. And, unlike a sail, you cannot trim this fin. You cannot change the angle of attack.

So if these new "compacted" tandem keels are working as well as the* promotional material* claims, then I would like to learn more about them.

Paulo said the tandem keels were the product of CFD studies but he was assuming that. I'd like to know if they were and I'd sure like to see the evidence so I can learn something. I am always looking for ways to reduce draft while preserving windward ability.

"Breakthrough" keels come along regularly. The Scheel keel was an attempt as was the Reijo Salminen wing keel to name two. Both worked, sort of and mostly because they lowered the VCG. But they are clunky keels and not good for boat speed. If the tandem keel preserves stability and windward ability *on an equal level* with a keel of reasonably deep draft then I would like to know more about it.

I am not going to buy into every piece of promotional material I read from any designer or any builder, even if I do read it on the internet.

I am waiting this morning for a new custom design client. He wants a variation of the 62 SLIVER project I have going now. Undoubtedly the question of draft will come up. I need to be prepared to present him with workable, efficient options. Talking the talk won't work for me. I have to be be ready to walk the walk.

Right now I believe I'll go walk my dogs.


----------



## PCP

Jeff_H said:


> Paulo,
> 
> I would like to comment that very often it sounds like you and I are disagreeing with each other when in fact, we seem to have similar opinions.
> I suggest that this conversation is one of those cases.
> 
> ....
> Where we sometimes go off the rails is in how we interpret what we read. For example: _"Digital tools enable us to optimise hull shapes, sail plans, appendages such as keels, and rudders for example, and to predict their performance based on outdoor conditions such as the wind, its strength, the direction its blowing from and the state of the sea. All of our yachts systematically undergo these simulation steps to guarantee optimized performance and handling. Structure is high on the agenda too, using finite element method (FEM) calculations. This equipment is systematically incorporated into our design procedure, for all of our creations." _
> 
> I think that statement is one that all of us come to general agreement on. But that statement does not describe the specific digital tools being used, and does not specify CFD. So while CFD may be used, it does not necessarily mean that Berret/Racoupeu does use CFD, or how they use CFD, or whether they analyze their keels and rudders using CFD.


Jeff, on their site there are several pictures of keels (and not from racing boats) going through CFD analyses. That seems to indicate that they use it on all their boats as they state on the site. I do not want to make this a discussion but if you look on the sites of European main NA offices many state that they are using CFD or high quality prediction speed programs that are based on CFD. Some don't say that explicitly on their sites but that does not mean they are not using it. In fact it its a lot less expensive to use that than tank testing.



Jeff_H said:


> This is similar to the two Mortain/Mavrikios statements:
> 
> "Those looking for small draughts will be delighted to know that cast-iron tandem keels &#8230;offer almost the same sail stiffness and the same ability to go close winded as lead keels with far deeper bulbs"
> 
> "The tandem keel is an alternative to the twin keel, it increases lift while reducing drag "
> 
> I think that we could agree that there is a possibility that these statements could be true. But where you and I, and perhaps Bob might not agree is the pieces of those statements which are missing.
> 
> If we look at the first statement, my interpretation is that it says two things, a that cast-iron tandem keels can offer almost as much stability as a deeper lead keel with a bulb, and that cast-iron tandem keels can point as high (i.e. close winded) as a deeper lead keel with a bulb. Properly designed, both may be true. And it does not take CFD to prove that statement to be true.
> 
> What that statement does not say is that cast-iron tandem keels designed to offer the same stability and pointing ability offer the same VMG as a deeper lead keel with a bulb.
> 
> And my sense is that the cast-iron tandem keels offering the same stability and apparent wind angle, cannot offer the same VMG, because by its very nature being cast iron, and shallower, the volume of the tandem keel needs to be greater than the volume of the deeper straight fin with bulb, and therefore there is more wetted surface, and therefore there is more drag, and therefore there is less speed for a given sail area, even if there is equal stability to carry that sail area.


In fact it says the opposite. The word "almost" implies they are less performant than deep draft bulbed keels but that is not the point. Both designers are not defending or sugesting tandem keels as an absolute performance keel but as the better performance in what regards a shallow fixed keel options, or one of the best options regarding that.

Defline compares the performance of shallow tandem keels with the performance of twin keels implying that they are both the most efficient options in what regards swallow draft keels.

Both are not as performant as deep bulbed keels and they have to be heavier to produce the same RM. There are an interesting detailed comparison made by Marc Lombard using one of those programs I was talking about, between the performance of both keels (twin keel and deep keel) on the same boat (a RM) with different wind speeds and wind angles that can give a very approximated idea of the differences.



Jeff_H said:


> The second statement can be viewed similarly. To me that statement says that properly designed a tandem keel offers greater lift relative to drag as compared to a twin keel. It does not take CFD to find agreement in that statement.
> ...
> In other words, without CFD its pretty easy to see that this claim could be true. On the other hand, there was an assumption that the downstream keel foil of the tandem keel produces the same lift as the twin keels, and it is here that this statement may go off the rails. I do not believe that to always be the case, and it would be next to impossible to make that kind of universal statement since the reality of this is so dependent on the specific design, and conditions.
> ...
> It is for those types of reasons that perhaps I sometimes view these kinds of designer statements with perhaps more skepticism than your comments appear to reflect.


Jeff, what make the use of CFD and high end based speed prediction programs is that while they are hugely expensive if you use them often they are much less expensive than tank testing with very close results. If an office designs a significant number of boats such a program is a very efficient, easy to use toll that can give very valuable help in what regards hull, keel and ruder design options/efficiency and that's why it is widely used by major NA offices.

Regarding the use of CFD or high end speed program analyses on the design of those keels it seems probable that they have used that but if not I don't believe they had done the design without a lot of studies and tests. That is a keel that only works well if properly designed and the design is more complex than the one of a normal bulbed keel.

Mortain-Mavrikios had used them in several designs and they designed them also for Etap that says:

*"After thorough investigation and numerous tests, ETAP Yachting N.V. is pleased to introduce its ETAP tandem keel. The most important advantages of this keel are the excellent sailing qualities at a considerably reduced draft. This new design is the result of a co-operation with the architects' bureau Mortain-Mavrikios."
The two most important features to reduce drift, are the size of the lateral plan and its efficiency. The efficiency is defined by the proportion between the depth of the keel and the length. *

So it seems a lot of testing, computer or not was going on.

Regarding Defline, that is one of the most talented new generation French NA and puts performance very high in what regards cruising boat design I know a bit more. I know that he uses a very high end prediction speed program as a toll to help to design his boats and I know also that before using a tandem keel on a 43 foot fast performance cruiser he had done not only computer speed testing but live testing replacing the keel of a First and tested the performance before and after.

This is the Defline 43, a fast voyage boat. The boat was tested by a French magazine and they said that with 10K of wind the speeds were not far from the wind speed. Not bad for a boat with a shallow keel








[/QUOTE]





You can see the care with weight distribuition with the engine over the ballast.

Regards

Paulo


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## outbound

Feel some level of responsibility for this back and forth given I was the first to mention a 20+ yr. old tandem keel design. Having said that and noting how much useful information I have gained from Jeff and Bob and how little from this distraction concerning CFD let's please agree CFD exists - it it used by some NAs and my Aunt Tilly - as with all technologies it continues to be devloped and doesn't answer all possible questions to be asked. Please move on and continue to educate me and the others following this thread.


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## bobperry

Oh come on Outbound. I swear I saw the horse twitch a little bit.
His eyelid moved.

Morelli and Melvin, designers for two of the big AC cats does not use CFD.


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## outbound

As regards CFD went to engineering school for a while before doing what I do now. Remember a professor talking about materials design saying : 'we do the math, then build it and see if it breaks'.


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## wolfenzee

Call me old fashion, but I prefer the beauty and grace of an old design over the extra knot or two I would gain in light air from the boats whose esthetics are.....well actually they aren't.


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## PCP

bobperry said:


> ....
> 
> Morelli and Melvin, designers for two of the big AC cats does not use CFD.


If you say so, but on the design team EMIRATES TEAM NZ DESIGN TEAM, and on Morelli and Melvin design team for EMIRATES TEAM NZ they have specialists in VPP and CFD and I don't believe they are there only for the ride. The same with Luna Rossa design team, in what regards CFD and VPP specialists and all the other teams for that matter.

http://www.sail-world.com/multimedia/EMIRATES TEAM NZ DESIGN TEAM1.pdf

http://www.morrellimelvin.com/emiratesteamnz/team.html

http://luna-rossa-challenge-2013.americascup.com/en/team#design

Regards

Paulo


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## bobperry

Paulo:
I would be extremely surprised if someone working with any of the AC cat teams did not do some CFD. But given the seat of the pants revisions to the designs it appears they should have done more. Because M&M did not do the CFD does not mean that someone else didn't do it.

My comment about M&M was made because Jody Culbertson who does my 3D rendering work has also been working with M&M on a cat project (not AC). We discused this today, this morning. He asked M&M about doing some CFD work on another project he was involved in and Gino told him they did not use it. They use VPP's. This is not first hand information. But it is second hand. I did not read it on the internet.

The horse is really still now. Doesn't look good. Probably playing possum.


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## PCP

bobperry said:


> My comment about M&M was made because Jody Culbertson who does my 3D rendering work has also been working with M&M on a cat project (not AC). We discused this today, this morning. He asked M&M about doing some CFD work on another project he was involved in and Gino told him they did not use it. They use VPP's. This is not first hand information. But it is second hand. I did not read it on the internet.
> 
> The horse is really still now. Doesn't look good. Probably playing possum.


Bob, I was not doubting. M&M have a specialist in VPP in their design team but then VPP is strongly based on CFD. They are very complex program with its roots in it. Some work directly with CFD, some use programs that are based on. Both are very powerful computer analytic tools that can predict how a boat will behave and can help boat design. On AC teams they have both, CFD and VPP specialists.

Regards

Paulo


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## bobperry

Paulo:
Thank you for educating me. If you had been around 35 years ago I might have made a name for myself in this business.

I herebye declare this horse well and truly dead.


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## PorFin

bobperry said:


> Paulo:
> Thank you for educating me. If you had been around 35 years ago I might have made a name for myself in this business.
> 
> I herebye declare this horse well and truly dead.


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## PCP

bobperry said:


> Paulo:
> Thank you for educating me. If you had been around 35 years ago I might have made a name for myself in this business.
> 
> I herebye declare this horse well and truly dead.


Bob, I don't know why you find everything I say offensive I was just trying to say this regarding the correlation between the more advanced VPP computer programs and CFD:

"CFD programs do not calculate how fast a boat of any type will pass through the water or predict the time to complete a course around the buoys. Predicting speed on a racecourse is the domain of another class of programs called Velocity Prediction Programs or VPP. *The VPP makes use of 
lift and drag numbers calculated in a CFD program to estimate the speed about will sail a course given the sail drive forces and the stability or righting moment of the hull*.

The VPP is a closed loop simulation continuously varies estimated speed and resulting lift, drag and righting forces until retarding and driving forces are balanced and a stable speed results. A CFD program on the other 
hand is an open loop simulation that simply states that given an angle of heel and speed for a specified hull and appendage configuration, here are the forces that will result for that instant in time. No consideration is given to how the vessel achieved that speed or sailing condition."

http://www.vacantisw.com/articles/computational fluid dynamics.pdf

I am quite sure you know the relation of a powerful VPP program with a CFD program and know that M&M use advanced computer simulations to develop their hulls but this is a Forum and most here don't know how an advanced VPP works or its relation with a CFD. I like to share the little knowledge I have and contribute to a more informed forum.

Regards

Paulo


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## outbound

paulo with all due respect the problem is you are not. many here work with computers daily either doing cad/cam,economic predictions,hard science or medical science. we are aware of various types of multivarient analysis, basic and complex statistics,vecter analysis, engineering design and the various purposes computing can be put to. however, we are less informed as to why we get on some boats and they sail well, we are comfortable, everything is in the right place and we feel confident in all weathers and get on other boats and at some organic level it's just not right. Jeff and Bob have been teaching us why some things work and some don't. all boats are compromises. I been learning why I made the choices I have. I know what I want in a blue water vessel but I don't know why on a detailed level. it is self evident anyone in the competitive environment of yacht design will make use of what tools they can to produce the design their client desires. they have been the guides to understanding our desires and how they try to meet them . you have not. please allow the discussion to move on.


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## blt2ski

outbound, you hit it. did that with a block wall I had to build for aclient once. I could see generally how to design it, BUT, I had a feeling it was not quite right. Talked to some one, he cranked a few numbers, said do it this way, even tho the design specs said do it that way! Glad I did it this way, as a 5 something quake hit a yr or so later. While I will not say the wall would not have held as the spec said, the way it was built, it did hold up with more wt behind than initially though!

Like all things, there is more than one way to skin a cat! or dog, or catfish or __________!

If someone can get a full keel to plane at 2x the hull speed of a boat, I'll buy one, if not, I'll take the fin thank you very much!

marty


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## Jeff_H

The moderators have moved two off topic post to Holding for further review.


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## copacabana

Jeff, I don't see the thread in the off topic forum. I think it's a shame to move it there over a few differences of opinion, especially when it's one of the more informative threads going right now on SN. Unless I missed something, it's been pretty civil so far.


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## Jeff_H

It is not being moved to "Off-Topic". Two posts were moved to a thread that only the moderators can see. We were asked to disclose when we moved things out of sight. That is why the bread crumbs were left.


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## copacabana

OK. Thanks for the clarification.


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## keforion

Still going,eh?

Seems to me that one of the design problems with modern beamy hulls equipped with high aspect ratio and deep fins, and the resulting high bending stresses at the foil to hullbottom join, could be alleviated by using two foils, in a "V" configuration, with the bottom ends joined at the ballast bulb below and the top end affixed to the hull near the chines or bilges. The foils then are in almost pure tension and compression, aside from the lift force, with almost no bending stress.

Has anyone tried this?

K E Froeschner
Martin, Froeschner & Associates
Morgan 45 "Orion"


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## bobperry

Kefer:
Not a bad idea. In a heeled position one leg of the fin woud be near vertical and that's good. The problem with any configuration of "tandem" keel isthat you have two trailing edges and more drag. There are a number of way to join high aspect ratio fins to hulls. On the SLIVER project we spread the loads out with a series of steel floors that all fasten to the outboard longitudinals that form the front of the setee faces. Keel bolts are well outboard in a T flange and extend all the way up through the floors. I'll see if I can find a photo.

The problem we had with the SLIVER was that the strip planked cedar hull was not capable of taking the keel bolt compressive loads without crushing. So we have to take the loads off the skin entirely. The wood strip planking was removed in a big pan shape around the keel and replaced with solid laminate.

Ok, found one:


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## keforion

Bob:

Thanks for the reply and photo of Sliver's floors. Looked up "the Sliver Project" on the web ... OUTSTANDING.

Nice to read of your love of Wm. Garden. I checked his books out of the libary as a kid and pored over them for so long that they eventually fell apart -- maybe it was just books with his designs in them. And your love of 30 Square's as well. There was one moored in Mariner Lagoon for years that I drooled at. It was eventually hauled to Svendsen's in Alameda and rebuilt by Peter Schwab. He raced in the Singlehanded Transpac to Japan, but I can not recall the result. (Probably won.)

Sorry for the thread drift -- but, just had to thank you.

"Bob, You done good."

kef


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## bobperry

Kef:
I still have the Garden design catalog he gave me whan I was 15 years old and depsite being referred to and read countless times I am happy to say it is not falling apart. I know where it is right now. I always know where it is. Wish I had had the brains to have had him sign it.

The SLIVER Project boat was moved last week to the yard in Seattle where it will be finished. Here are some pics


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## Jeff_H

One of the things which is happening on the more extreme versions of the small root keels is that they are building 'cassette' style keel connections in which the end of the keel inserts into a tightly fitting box inside the hull. This allows a much bigger contact area to resist bending and torsion. Of course the box needs to be heavily constructed and needs a sophisticated transverse and longitudinal framing system to be able to distribute loads outward into the hull. 

FWIW I like Garden's work aesthetically and from a historic point of view. 

Jeff


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## mstern

Jeff_H said:


> One of the things which is happening on the more extreme versions of the small root keels is that they are building 'cassette' style keel connections in which the end of the keel inserts into a tightly fitting box inside the hull. This allows a much bigger contact area to resist bending and torsion. Of course the box needs to be heavily constructed and needs a sophisticated transverse and longitudinal framing system to be able to distribute loads outward into the hull.
> 
> FWIW I like Garden's work aesthetically and from a historic point of view.
> 
> Jeff


That sounds like what Seaward does with its retractable keels; the high aspect keel slides up and down a box that looks (at least on their website's videos) to be rather robustly incorporated into the hull. Makes sense as a way to spread the load of a grounding even if the foil is nonmoving.


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