# Low vs. high freeboard - benefits and drawbacks



## krisscross

I know the theory when it comes to low vs. high freeboard, but how does it actually affect sailing in general, and sailing in heavy weather in particular.
Low freeboard = less windage, less weight (potentially faster).
High freeboard = more room below, drier boat, and so on.
Input from sailors experienced with both respectfully sought.


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## Alex W

I think a higher freeboard allows a wider beam. If you figure that you want to be able to heel at least 20 degrees without dipping the rail then you'll also need additional freeboard as you make the boat wider. If I'm not forgetting my basic trig that means that for each foot of beam you'd want about 2" more freeboard, everything else being equal.

My Pearson 28-2 has about 3" or 4" more freeboard compared to the Yankee 30s that I also sail on. It is also about 1' wider. It seems like this relationship holds true on these boats, we both dip our rails at a little over 20 degrees of heel.

You could compare the freeboard on the very similar Tartan 30 and Yankee 30 to see if S&S also raised the freeboard on the Tartan 30 to match it's wider beam. There are drawings for both:
http://3.bp.blogspot.com/-OhceXLWL1.../s1600/2016-Tartan+30+arrangement+plan300.jpg
http://2.bp.blogspot.com/-xue6-fbVn.../s1600/1999+Yankee+30+arrangement+plan300.jpg
http://4.bp.blogspot.com/-MkZqmZQo8...AMfUOKU/s1600/2016-Tartan+30+sail+plan300.jpg
http://3.bp.blogspot.com/-Z3Co4aPHk...64OGjT8/s1600/1999+Yankee+30+sail+plan300.jpg

The boats were designed 2 months apart from each other and have a lot of design elements in common except for the beam. It looks to me like their freeboard is pretty similar, but I haven't fired up Gimp to measure.

Edit: I did measure in Gimp. Measuring at two points (front of cabin, and top of transom) it looks like the Tartan 30 has 2.5" to 3" more freeboard to go along with the 1' wider beam.


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## zeehag

storms i experienced in low freeboard sloops have been wet in boat. 
my high freeboard formosa is dry in weather. can make the difference between comfort and endurance..


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## capecodda

We've pretty much stuck with low freeboard boats. Yes, they are wetter. Yes they have less windage. Yes, they have less interior volume for their size. Lots of traditional boats have low freeboard. Lots of newer designs don't, but I think they show better at boat shows when you go below and imagine living on them. 

Overriding these concerns is, well, IMHO they are just better looking boats. Too much freeboard on too short a boat just doesn't look right to us. So to me at least, it's an issue of proportion. You can have more freeboard on longer boat, but in general there is some ratio that works best to the eye.

Pretty superficial I guess, but it is what it is. Life's too short to have an ugly boat, but beauty is in the eye of the beholder. We like low freeboard. It's a tradeoff.


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## krisscross

capecodda said:


> Overriding these concerns is, well, IMHO they are just better looking boats. Too much freeboard on too short a boat just doesn't look right to us. So to me at least, it's an issue of proportion. You can have more freeboard on longer boat, but in general there is some ratio that works best to the eye.


Never really thought about it in terms of aesthetics, but a lot of times natural beauty also translates into safety and/or performance. I think that boats with too much freeboard have a higher center of gravity and thus have to compensate for it with more ballast and more beam, something that Alex brought up earlier.


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## krisscross

zeehag said:


> storms i experienced in low freeboard sloops have been wet in boat.
> my high freeboard formosa is dry in weather. can make the difference between comfort and endurance..


That would be especially important when sailing in higher latitudes and colder waters.


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## Alex W

The major performance downside is extra windage. This can be painful when close hauled, and doubly so since many high freeboard cruising boats also have dodgers with a lot of windage. I also find the windage annoying when docking in a blow.

The interior space advantages of extra freeboard and beam are nice. A beamy ~10' wide 30' boat gives up a little performance but gains a lot of interior space compared to a narrower one. The extra freeboard allows the settees to be placed closer to the edges of the boat without crowding shoulder space and usually give room for storage along the inside of the gunwales. 

I prefer the lines of a lower freeboard with a nice shearline and reduced beam. My wallet prefers the $80 cheaper moorage that I get by having the interior volume of a 31-32' boat in a 28.5' envelope, and that only happened by increasing beam and freeboard by a few inches. When it is 35 degrees out and blowing I also do like the drier ride.


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## Alex W

krisscross said:


> I think that boats with too much freeboard have a higher center of gravity and thus have to compensate for it with more ballast and more beam, something that Alex brought up earlier.


I think you misunderstood my point about beam, though it can help with form stability.

As you make the boat wider the leeward gunwale gets closer to the water for a given heel angle. You need to raise the freeboard to compensate if you want to keep the rail out of the water. For a 20 degree heel angle (excessive on most boats, but not so excessive that you want the rail under water) you need to raise the freeboard about 2" for every foot of beam that is added.


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## baboon

Low freeboard boats can be an advantage docking as well. Not only are they blown around less, but the step off on a high freeboard boat can be a problem, especaily if you visit other marinas often.


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## capecodda

For an extreme example of how beautiful (again by my taste) a low freeboard boat can be, google images for sailing yacht Rebecca. Extreme low freeboard with extreme size.  Wow. Much nicer looking than say a Perini but I'm sure the interior would be small by comparison for comparable length. We've seen her a few times, never invited aboard 

A B40 yawl has the same effect on us. It just looks right.


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## krisscross

Alex W said:


> I think you misunderstood my point about beam, though it can help with form stability.
> 
> As you make the boat wider the leeward gunwale gets closer to the water for a given heel angle. You need to raise the freeboard to compensate if you want to keep the rail out of the water. For a 20 degree heel angle (excessive on most boats, but not so excessive that you want the rail under water) you need to raise the freeboard about 2" for every foot of beam that is added.


No, I got that, but just wanted to bring up the center of gravity/stability issue to the beam/high freeboard ratio.


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## svHyLyte

krisscross said:


> I know the theory when it comes to low vs. high freeboard, but how does it actually affect sailing in general, and sailing in heavy weather in particular.
> Low freeboard = less windage, less weight (potentially faster).
> High freeboard = more room below, drier boat, and so on.
> Input from sailors experienced with both respectfully sought.


Within reasonable limits, there is merit to the increased free board although it may not be aesthetically pleasing. A good comparison is Hinckley's B-40 and later OC-40 (a B-40 but with a straight rather than sprung shear). The B-40 is a great sailer but damned wet to weather compared with the OC-40 which some do not find so aesthetically pleasing. Holding to the "form follows function" principal, however, the OC-40 is the better yacht.

FWIW...


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## ehmanta

My boat has a moderate beam but looks much lower than modern boats of the same length, of course modern boats have wider beams too. I feel that the designers of my boat know how to design a boat that is fun to sail, seaworthy and aesthetically pleasing.


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## TomMaine

capecodda said:


> Overriding these concerns is, well, IMHO they are just better looking boats. Too much freeboard on too short a boat just doesn't look right to us. So to me at least, it's an issue of proportion. You can have more freeboard on longer boat, but in general there is some ratio that works best to the eye.
> 
> Pretty superficial I guess, but it is what it is. ... beauty is in the eye of the beholder. We like low freeboard. It's a tradeoff.


I'm with you, and it's strictly taste. I prefer the look of low freeboard boats, new or old, and accept the drawbacks(especially less volume).

I also prefer the feeling I get being closer to the water while sailing or at anchor in the cockpit and on deck.


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## travlin-easy

I have a high freeboard, wide beamed Morgan 33. In the nastiest weather I'm sitting high and dry, while the guys in the lower, narrower boats are getting slammed and drenched. The only time this has been a bit of a problem was when docking on a very windy day, but that's probably true with any boat, high or low sided. I suspect the winds action on the furled sails and mast have more bearing on this than the freeboard.

Now, I'm a cruiser - not a racer. So, if the boat goes a half-knot slower because of the freeboard height I could care less. I enjoy being warm, dry and comfortable while sailing in marginal weather. Additionally, I don't enjoy dipping the rails, which some folks tend to believe is really neat. If my boat heels 10 degrees that's a lot, which is fine with me. To me, it's neat to lock the helm, trim the sails and allow the boat to track in a perfectly straight line for miles on end while I sip Margarettas and listen to Jimmy Buffett music. 

Cheers,

Gary


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## ehmanta

travlineasy said:


> To me, it's neat to lock the helm, trim the sails and allow the boat to track in a perfectly straight line for miles on end while I sip Margarettas and listen to Jimmy Buffett music.
> Cheers,
> Gary


Yes, It's quite nice when the helm is balanced! My S&S design does that quite nicely, But I never drink when underway, always wait until the anchor is held fast.


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## Minnesail

What is considered a high or low freeboard?

Would you take the ratio of freeboard over LOA? My little boat only has about 2' 4" (obtained by measuring in Photoshop), so that would give F/L of 0.1.


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## bobperry

If you are out there is 8' breaking seas 6" more or less freeboard will not mean the difference between being wet or dry. High freeboard provides volume and that's about it. I can think of nothing else to say good about it.


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## JonEisberg

capecodda said:


> We've pretty much stuck with low freeboard boats. Yes, they are wetter. Yes they have less windage. Yes, they have less interior volume for their size. Lots of traditional boats have low freeboard. Lots of newer designs don't, but I think they show better at boat shows when you go below and imagine living on them.
> 
> Overriding these concerns is, well, IMHO they are just better looking boats. Too much freeboard on too short a boat just doesn't look right to us. So to me at least, it's an issue of proportion. You can have more freeboard on longer boat, but in general there is some ratio that works best to the eye.
> 
> Pretty superficial I guess, but it is what it is. Life's too short to have an ugly boat, but beauty is in the eye of the beholder. We like low freeboard. It's a tradeoff.


More than a "superficial" distinction, seems to me... Excessive freeboard is generally the result of a boat being designed from the inside out, around an interior accomodation plan, which rarely results in stellar sailing or seakeeping qualities... It might work at the boat shows, but not necessarily offshore...

Since the OP cited heavy weather ability, I'll take lower freeboard over higher every time... For me, one of the most essential characteristics in an offshore boat, is one that will heave-to easily... Excessive freeboard, particularly forward, can make doing so a real challenge...

You're not gonna find much lower freeboard on an offshore boat, than is seen on the legendary Contessa 32:










John Kretschmer affectionately dubbed the Contessa 32 he sailed around Cape Horn a "submarine", due to the amount of water she could ship on deck... And yet, after all these years, he still considers that boat to be one of his favorites:



> Contessa 32 - A classic, incredibly well proven boat that is close to my heart. I sailed Gigi across the Atlantic and around Cape Horn. My book Cape Horn to Starboard is being reprinted this year. Arguably the most loved production boat of all time in England. Noted for extreme seaworthiness and the sweetest motion afloat. Also noted for small living space and very wet on deck.
> 
> John Kretschmer Sailing - Bluewater Boats


Of course, the reputation of the Contessa 32 was built largely on her performance in the '79 Fastnet...

Fastnet 79 - The winner's story | Yachting World

Willy Ker certainly doesn't seem to think low freeboard is a particular liability... 

Quite the sailor:


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## outbound

Current boats of pretty much all sizes seem to have greater freeboard than in the past. Because of this and perhaps for "modern" fashion they also incorporate portlights in the hull.
I find these hull port lights to be ugly and remain concerned they represent a point of potential catastrophe should they break/leak or get blown out. In a knock down I think it is easier to design a boat that will survive without high freeboard and hull windows. Some will argue a beamy high freeboard boat is less prone to a knockdown but again there are multiple features of design that enter into that conversation. 
Wetness underway even beating depends on multiple factors. The old B40 did incorporate substantial cockpit coamings. I've sailed those to Bermuda and back and did not find them especially wet. Most boarding water occurs when the bow goes under and the deck is awash or when a wave strikes the forward quarter causing spray or the top of the wave to enter the cockpit. To expect to stay dry outside the cockpit is an unreasonable expectation in my view. Although other features can overcome inverted stability it is easier to achieve a good looking boat with good GZ and other features by not taking beam and freeboard to extremes. It is harder to avoid the clorox bottle look in a high freeboard boat. 
My current boat has much higher freeboard then prior vessels. However it is in proportion to its size ( and she is beautiful in my eyes).


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## SailingJackson

TomMaine said:


> I'm with you, and it's strictly taste. I prefer the look of low freeboard boats, new or old, and accept the drawbacks(especially less volume).
> 
> I also prefer the feeling I get being closer to the water while sailing or at anchor in the cockpit and on deck.


High freeboard boats remind me of Winnebago RV, Greyhound bus, and the Goodyear blimp.

Low freeboard boats remind me of Ferrari, Jaguar, and similar. Not only look do they look better, but the connection they have to the road is similar to the connection to the water that a low freeboard boat has.

Having said that, I can assure you that do get wet, even when they are bigger. I chartered a classic style 44' boat for a week. Most of the time we had the rail under the water and frequently waves in the cockpit. It was a fun week but I would not want to cross an ocean like that.

GTJ


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## PCP

krisscross said:


> Never really thought about it in terms of aesthetics, but a lot of times natural beauty also translates into safety and/or performance. I think that boats with too much freeboard have a higher center of gravity and thus have to compensate for it with more ballast and more beam, something that Alex brought up earlier.


Regarding aesthetics a modern tendency (on well designed boats) seems to have boats with high freeboard hulls but then compensate with a much less higher cabin. If well designed they can give the idea of a more elegant and overall less high boat, for the same interior height.

Regards

Paulo


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## outbound

A drop dead beautiful boat known for its "wetness" is the Cherubini s. Think some of that is also due to beam. Narrow boats maybe more prone to green water. However in choosing between a Cherubini 44 ketch and a forty something Bene think most would take the C44 and smile.


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## mad_machine

Alex W said:


> I think a higher freeboard allows a wider beam. If you figure that you want to be able to heel at least 20 degrees without dipping the rail then you'll also need additional freeboard as you make the boat wider. If I'm not forgetting my basic trig that means that for each foot of beam you'd want about 2" more freeboard, everything else being equal.


I think your Trig fails to take into account buoyancy. If a vessel simply tilted on it's CG, then a wider boat would dip it's rail much faster than a narrow boat. However a wider boat would have much more buoyancy for a given angle of tilt and would also pick up the upper rail rather than simply submerging the lower.

All you need do is look at a Catboat for it to be self evident. They are very wide and usually have very low freeboard. I saw one racing on Barnegat Bay that not only had it's rail dipped, but the base of it's Centreboard was out of the water


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## krisscross

mad_machine said:


> All you need do is look at a Catboat for it to be self evident. They are very wide and usually have very low freeboard. I saw one racing on Barnegat Bay that not only had it's rail dipped, but the base of it's Centreboard was out of the water


I have a wide dinghy with low freeboard (Holder 14) and I sometimes sail like that in high winds. When hiked out on the rail I can see my dagger board starting to come out of the water. That board is really the only thing keeping the dinghy from tipping over. Then I know I have to ease out the main sheet to de-power the sail. Not sure if higher freeboard would have made much difference in that case.


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## bobperry

Buoyancy is always moving to leeward as you heel through the first say 80 degrees. It differs with different boats. You can look at a stability curve and see when the center of buoyancy begins to move back towards center That's where stability comes from.

" Where does stability come from Daddy?"


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## Alex W

mad_machine said:


> I think your Trig fails to take into account buoyancy. If a vessel simply tilted on it's CG, then a wider boat would dip it's rail much faster than a narrow boat. However a wider boat would have much more buoyancy for a given angle of tilt and would also pick up the upper rail rather than simply submerging the lower.
> 
> All you need do is look at a Catboat for it to be self evident. They are very wide and usually have very low freeboard. I saw one racing on Barnegat Bay that not only had it's rail dipped, but the base of it's Centreboard was out of the water


It will rotate near the VCG, right? For a keelboat that is typically somewhere in the cabin and my relationship is approximately true. A modern boat with a bulb keel will get it lower. For a centerboard boat with no keel (like that catboat or my 5o5) it will be much higher.


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## bobperry

Alex:
No. It's a bit complicated. But if you extend a vertical line from you center of buoyancy upwards until it crosses the heeled centerline you will get the metacenter of the boat. The boat rotates around the metacenter as it heels. So they say. It's one of those things that is very hard to feel in the seat of your pants.


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## Alex W

Does the metacenter (or more specifically the center of buoyancy) move towards the center as the vcg moves down? It intuitively feels like it should, but I would have to draw it out.

Where is the metacenter on a typical small/medium cruiser/racer?


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## ericb760

I sail regularly on two boats. My own S&S Yankee Dolphin with very little free board, and the boat berthed next to me, a Ranger 29. First off, I STEP on to my boat, my friend uses a ladder to CLIMB UP to his. Under sail and at the helm of the Ranger, I feel like I'm driving a bus and that I'm a long way from the water and feel that I have less overall "situational awareness". By contrast, my Dolphin responds to the slightest tiller input and I feel much more in control and aware of what's going on around me. Perhaps both of these are simply my perceptions, but, I much prefer my boat when I'm the one in command. But, darn, it sure would be nice to stand up straight when I'm below decks...


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## bobperry

Alex:
I don't want to get into this. It's too hard to explain without pencil and paper.

I'll give it a shot:
The distance between the Metacenter and the VCG, measured along the heeled centerline is called the GM. As the VCG goes down the GM increases. GM is one way of defining stability. You want a long GM. You use the metacenter M when you are doing an inclining test to determine the transverse GM and from there calculate the VCG.

Like I said, it's a hard concept to get a feel for. I prefer to describe stability as Rm, righting moment, or the distance between the VCG and the TCB measured horizontally. You sometimes see this distance referred to as the GZ. If you multiply the GZ times the displ of the boat you get Righting Moment, Rm. I find Rm more "tactile". In the end they are all essential parts of the same picture.

Skene's gives a range of GM's for sailing vessels between 3' and 4.5'. You know the FRANCIS LEE. That boat has a GM of 4.5'.


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## bobperry

I think I scared everyone away.
Math can do that.


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## Jeff_H

Olin Stephens was quoted as saying that the best boats were the ones that were designed in moderation. Looking at the majority of Bob Perry's work, I would venture to guess that he would agree, but I don't want to put words in his mouth. 

If ever there was a classic case, where moderation should be exercised in the design process, I would suggest that it is in the amount of freeboard on a boat. Too little freeboard, and the design is giving up reserve stability thereby reducing your LPS, as well as, making it harder to create a dry boat, and creating a boat which is less forgiving since it dips the rail at smaller heel angles, an event which generally changes the sailing capabilities for the worst. And that does not touch on the negative impact of too little freeboard on accomodations. 

Too much freeboard, and you have excessive windage the negatives of which is mentioned above, the vertical center of gravity is raised by the weight of the deck reducing stability, the vertical height of the crews heads and bodies are raised making rotational motion seem more extreme (somewhat like the whip cracking effect), and its hard to avoid a homely boat. 

In reality, the best answer lies at sweetspot in between. Consistently finding that exact sweetspot is but one example the fine art that makes a skilled yacht designer, a skilled yacht designer. 

I would also say, that freeboard is only one small part of what causes a wet boat. After all even large ships will take spray across the deck in certain conditions. Hull shape (both above and below the waterline) figures in as well. Careful hull modeling will minimize the amount of water that gets on the deck and/or makes it back to the cockpit. 

But also speed comes into play as well. Fast boats hit waves at higher speed and will tend to throw more spray. If the boat is shaped right with some flair and a rub rail to throw the spray outward, that does not mean that a fast boat necessarily will be wetter. But as a general rule, a slow boat will tend to be drier. 

Jeff


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## knuterikt

bobperry said:


> I think I scared everyone away.
> Math can do that.


I think that one thing making it difficult to grasp is this.
The CG (center of gravity) remains the same with the same load on the boat - regardless off heeling angle.

But the CB (center of buoyancy) will shift as the boat heels since the shape off submerged part of the hull is changing.

As a result of this the boat will not rotate around a fixed axis.

There is and good explanation here


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## PCP

outbound said:


> A drop dead beautiful boat known for its "wetness" is the Cherubini s. Think some of that is also due to beam. Narrow boats maybe more prone to green water. However in choosing between a Cherubini 44 ketch and a forty something Bene think most would take the C44 and smile.


I am not so sure, it is all a question of personal taste


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## Minnesail

bobperry said:


> I think I scared everyone away.
> Math can do that.


Speaking of the maths, back to my ratio thing. Does anyone calculate freeboard over length or freeboard over beam ratios? Or is that just dumb?


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## bobperry

Yeah, that's a good explanation but not ethe part that say that the M stays pretty constant at low heel angles. In calculations for stability for yachts that I have seen the M is considered a fixed point. As I said, "feeling" the metacenter" is difficult. Changes in VCG can be easily grasped. Changes in submerged volume are easy to imagine. But feeling that point on a line that doesn't exist and that is not connected to anything can be a challenge.

One of the best ways to understand stability is to take a week and do the calculations by hand. I have done this. It's not a lot of fun until you are done. Or, take a day and incline your own boat. We did this all the time back in the IOR days to get a Rm at 1 degree for the rating. Todsay, computers take all the fun out of it and in that way remove the human element so the elements of the process tend to get obscured.


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## bobperry

The Cherubini is a very American boat Paulo. We think of that kind of boat as very traditional. That look goes back to the schooner AMERICA. I would not expect you to relate at all. But to many US eyes the high freeboard, Euro bloated tennis shoe look is not appealing. But I understand how important fashion is in Europe.

Personally, I don't like any of those boats uncluding the Cherubini. The dark blue one is OK but that look is becoming so very boring. I suspect the boats I find apealing would look boring to you. Personal taste is just that, personal. Can't see any point trying to dictate taste.

Minn:
That is a very interesting idea. I might try that. I've never seen it calculated. Freeboard as a percentage of LOA would be fun to track.
What I have been doing in my reviews as a reaction to the ultra boxy looking European models is to calculate what percentage the beam at the transom corner is of beam max.


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## knuterikt

bobperry said:


> Or, take a day and incline your own boat. We did this all the time back in the IOR days to get a Rm at 1 degree for the rating.


The process of doing a Inclining test wast part of the curriculum in "Stability and loading" when I took my license, but I have never done this on my boat.


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## bobperry

Knut:
I'll see you at the dock Saturday morning. Bring some big barrels. We can tip your boat over.
I'll bring my wife. She was an exchange teacher in Bergen. She loves Norway.

For the record:
"Bloated tennis shoe" is not my term. I borrrowed it from Tom Larsen an astute observer of yacht design trends. Tom is Danish. Tom lives in Denmark. Tom's last boat was a Perry design.

For my take on the traditional American yacht look I did the Scorpio 72. They built ober 30 of these and 25 of them went to Europe. I am very proud that Maestro Vladimir Ashkenazy owns one of my designs.


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## knuterikt

bobperry said:


> Knut:
> I'll see you at the dock Saturday morning. Bring some big barrels. We can tip your boat over.
> I'll bring my wife. She was an exchange teacher in Bergen. She loves Norway.


It's winter here now, boat is on the water but she is covered up and bubbled.

Filling barrels with water to add weight is not going to be pleasant this time of year either.

If you wait until summer I would be glad to show you the Oslofjord from my boat


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## bobperry

Thanks Knute. It sounds great. It's cold here too now, around 25 degs F today.


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## Alex W

Bob: Thanks for the explanations here and in other threads. It's really helping me get a better understanding, but I have a long way to go. I agree with you that righting moment is easier to understand (especially for anyone who has sailed a dinghy).

Knut: The wikipedia article was also useful, thanks for sharing it.

I'll be in Oslo in a few weeks, I'm lucky to get to travel there for work. Norway is a spectacular country and I really enjoyed a few hour paddle that I did around a little part of Oslofjord.


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## bobperry

Alex:
We all have a long way to go. Life is a voyage of discovery isn't it?

There are some quiet times when the blathering on and words on words no longer matter. It's reality time folks!


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## blt2ski

Lower free board is prefered, yeah maybe a bit wetter......but I'll take the 1st 45 over a cheribuni ANY day of the week! Again, it is ones prefered look. But some of the higher freeboard/low cabin boats like Hanse's, I do not like the look either. If you are going to go that route, look at a Pederson 2 ton from the IOR era, high freeboard, but NO cabin. ALA a J24, Moore 24 also. 

Marty


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## outbound

Some like blondes. Some like brunettes. They are all beautiful. Would defend myself by saying when I choose my "last boat" I didn't go for the traditional look. Still, sure like that 72'. Don't like the Benes Paulo was kind enough to post. Guess the angularity of them makes them more he then she and think of cruising boats as lovely ladies.


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## Barquito

I'm suprised nobody has mentioned one important functional aspect. It is easier to get back onto a low freeboard boat from the water. Could be important in a MOB situation. But, also just everyday dinghy gymnastics.

My Bristol 27 has a lower freeboard in the cockpit than my Catalina 22 had. Makes it a little easier to get onboard. I like my B27 asthetically, however, in order to get standing headroom, poor Mr. Alberg had to make the doghouse very high. Might look ugly to some.


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## PCP

outbound said:


> Some like blondes. Some like brunettes. They are all beautiful. Would defend myself by saying when I choose my "last boat" I didn't go for the traditional look. Still, sure like that 72'. Don't like the Benes Paulo was kind enough to post. Guess the angularity of them makes them more he then she and think of cruising boats as lovely ladies.


I was not trying to attack you. I love also traditional boats even if that kind of pocket clippers is not my favorite style in what regards classic boats. In Dusseldor I visited a preferred one that I had never had saw in the flesh. Absolutely wonderful boat with and incredibly "old style" interior and I bet a decent sailing performance. However I did not like the price, that was really out of this world, a bit like the boat. But it is impossible to have everything



As you can see, a very nice hull: 

http://www.scalaryachten.de/html/site/g/pdfs/hs_brosch_Scalar40.pdf

I guess I would not mind to have one of these when old enough

Regarding the boats to be a she in English, at least on the classical nautical language, it is masculine in Portuguese. Probably that can have influence on the romantic image we can have of a boat: A nice beautiful lady or a powerful Greek Adonis.

Regards

Paulo


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## TomMaine

Barquito said:


> I'm suprised nobody has mentioned one important functional aspect. It is easier to get back onto a low freeboard boat from the water. Could be important in a MOB situation. But, also just everyday dinghy gymnastics.


I have a friend a bit older that had a tough time getting on deck from the dinghy on a 34' higher freeboard boat. She has no trouble getting onto my boats decks, which are nearly a foot lower.

Small point as you can figure out a boarding ladder as you become older but I do appreciate an easy step from dinghy thwart to decks.


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## bobperry

Barquer:
Your Alberg looks great to me. Not sure Alberg drew any ugly boats.


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## Jeff_H

Barquito said:


> I'm suprised nobody has mentioned one important functional aspect. It is easier to get back onto a low freeboard boat from the water. Could be important in a MOB situation. But, also just everyday dinghy gymnastics.


I think that no one mentioned it since freeboard rarely comes into play in either situation these days. Modern safety recommendations require a permanently fixed boarding ladder, which is almost always transom mounted. Because of that, few people climb out of the water, or into and out of a dinghy, off of the side of the boat. Most use the permanently attached ladder in instead.

In reality, even with significantly lower freeboard, unless the person is extremely physically fit, without a ladder most people would be unable to grab the rail of a boat and haul themselves up over the rail. (Between my wet clothes and PFD, I found that nearly impossible to do even in a small powerboat that perhaps had only 18 inches of freeboard.)

And while I have seen three large and very strong men from a racing crew grab someone under the armpits and then their belt, and haul them aboard, even that was an extremely difficult thing to do. Frankly, an extra 8" or a foot or so of freeboard is not going to make much of a difference even there. Either you can haul the person up, or not.

Jeff


----------



## krisscross

Barquito said:


> I like my B27 asthetically, however, in order to get standing headroom, poor Mr. Alberg had to make the doghouse very high. Might look ugly to some.


What I really don't like on boats like that is not so much the higher doghouse but the big, square, ugly lexan windows mounted on them. I have seen some boats where owners glassed in these ugly holes and installed regular small opening ports in that space - matching the other ports. For me, that made a huge aesthetic difference and a safer boat.


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## svHyLyte

krisscross said:


> What I really don't like on boats like that is not so much the higher doghouse but the big, square, ugly lexan windows mounted on them. I have seen some boats where owners glassed in these ugly holes and installed regular small opening ports in that space - matching the other ports. For me, that made a huge aesthetic difference and a safer boat.


For a good example of this transformation, see the jacket of the first edition of Don Casey's "This Old Boat" © 1991.


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## HeartsContent

Wouldn't the higher volume of the high freeboard boats cause them to bounce around much more for a less comfortable ride? That's how they keep their bow out of the water, there's more volume.

The more bulbous, the tougher time these boats tend to have in light air and going to weather. I sail right on by these boats easily.

The more bulbous, the more headroom and it does impart a feeling of spaciousness. These boats tend to have "a lot" of storage space which is awesome if you are spending lots of time on them.

It depends on what your are going to do and what catches your eye.


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## Alex W

HeartsContent said:


> Wouldn't the higher volume of the high freeboard boats cause them to bounce around much more for a less comfortable ride? That's how they keep their bow out of the water, there's more volume.
> 
> The more bulbous, the tougher time these boats tend to have in light air and going to weather. I sail right on by these boats easily.
> 
> ...
> 
> Catalina 36 MKII


The Catalina 36 MKII is a high freeboard boat compared to many boats being discussed here and shown in photographs.

I don't think that you can assume that a high freeboard also means that the boat has a wide entry (which is what I assume you meant by bulbous). It is probably safest not to make those types of generalizations.


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## SVTatia

One example of high freeboard is the Downeaster 32, almost excessive, but it has lots of space and headroom for a 32'. Bob is right, the only advantage is additional space.

I had a high freeboard 30' by Brewer (Bull Dog) that had more space than some 35s, but although it sailed well (not to weather), it could not heave-to properly with main and jib, it needed just the reefed main as windage forward made up for the sail.


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## misfits

Some of the higher freeboard boats I've seen you need a step ladder to board them from a dock. If it wasn't for the walk thru transoms on most of these boats, getting in & out of a dingy would be an adventure in itself.


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## travlin-easy

High freeboard, wide beamed boats, in my experience, don't bounce around any more than any other boat of the same length and weight. My Morgan 33 O.I. rides smooth as silk on marginal weather days, beam is 13 feet and it's about 5-1/2 feet from the waterline to the gunwale.

Gary


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## GeorgeB

Funny, I never considered my C34 as high freeboard (about the same as a C36). Now, the Catalina 350s and Beneteau 361s are considerably higher than mine. IMHO, I suspect that boats with higher freeboards/cockpits are more uncomfortable. For example, on my C34, I can perch on the cockpit coaming and be perfectly balanced and not be constantly sliding to leeward. I can drive comfortably all day long. On my friend's 361, I cannot find that sweet spot and I'm constantly hanging on a lifeline to keep from sliding down. Is it because I happen to be sitting on top of the axis of heel rotation on my boat and not on my friends?


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## TomMaine

travlineasy said:


> High freeboard, wide beamed boats, in my experience, don't bounce around any more than any other boat of the same length and weight. My Morgan 33 O.I. rides smooth as silk on marginal weather days, beam is 13 feet and it's about 5-1/2 feet from the waterline to the gunwale.
> 
> Gary


You make me realize there's a huge range in freeboard among boats. I don't know the exact freeboard on my 38'er, but I can kneel on deck in the lifeline gate, bend and reach down enough to rinse out the coffee pot in the harbor. 

That makes neither boat better than the other. It just shows the vast difference between high freeboard/low freeboard, in how it feels, both above and below decks, at anchor or underway.


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## christian.hess

real world experience here:

I was on an H28 wooden boat, leaving perlas islands going to panama...I was not harnessed since it was a short trip and I was young and dumb...sort of...

I was lashing up the dinghy on the cabin top, and I pulled some line too harshly...

snap

went overboard.

No lifelines on this beatuful boat, my crew had no sailboat experience...

we were motoring...

I had such an adrenaline rush to get back to the boat I looked like a doplhin...it helped I was in boxers only...jajaj

freeboard was around 12-14 inches where I grabbed hold of the stern pulpit...climbed right back in before my crew even knew what to do...

THAT was a huge lesson....been carefull ever since

the biggest benefit if a low freeboard hull other than ease of getting back in and nice looking lines is less mass up top over the waterline

making motion at sea better...it also helps to fight windage...more mass you have above waterline the more it acts as a sail and you get stuff like weather helm poor steerage way, etc...

try putting your dinghy up on deck into 25 knot winds to weather or beam reach

do the same test without dinghy on foredeck

keen sailors will notice the difference, if you dont then get whatever freeboard boat comes your way

sailors especially new ones like more freeboard as itr gives them a better sense of security, true or not...

security in a hull comes from(in my opinion) bulkhead structures and watertight bulkheads and separation of stations if you will

a high freeboard boat with open structures down below is as easy to sink as a low freeboard boat, simply its when not holed, that it has more reserve buoyancy.

for example a RAWSON 30 with watertight bulkheads would probably be the ultimate high freeboard safe cruiser if taken advantage of...

anywhoo


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## Alex W

GeorgeB said:


> Funny, I never considered my C34 as high freeboard (about the same as a C36).


It is all relative, right?

My quick judge of freeboard height is simply how big of a step up or down is it to the boat from Shilshole dock height (Shilshole is a big marina in Seattle). The C-36 that I've sailed on at a local club has the highest freeboard of any boat that I've sailed on, though there are plenty of boats at Shilshole with even high freeboard.

Measuring the waterline to gunwale by the cockpit winches off of a drawing it looks like the Catalina 36 MK2 has about 41" of freeboard. For comparison a C&C 35 has 34" (7" less) and that Bene 361 appears to have a huge freeboard in the range of 47" (6" greater).

My own Pearson 28-2 is quite freeboardy for a smaller boat, with about 35". However that would be fairly low for a boat in the 35' range.


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## windnrock

Interesting discussion. Beyond forgiveness for screwing up, applying physics for certain conditions or simply pleasure to the eye, much depends on where you go and what you will face. No boat is perfect for every condition. My Bristol 41.1 gives us good usable interior room, a pleasing appearance (to me) and some characteristics that keep her pretty dry. The freeboard at the bow is close to 4 1/2' while tapering to about 3' at the stern. In heavy weather she stays incredibly dry. We make choices with compromises on virtually everything. Safety, cost, convenience and form all play a part. For us vessel size was driven by capacity/storage and sail plan. The fact she is, in our eyes, a beautiful boat didn't hurt! With a centerboard that gives us about 11' up wind if we need it, the windage is not a big issue. The fact that the bow cleaves large waves like a knife does make a real difference.


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## Sail444

I would recommend low freeboard, for offshore cruising. Less windage, and presents a smaller footprint for beam seas.

Fair Winds,
Steve Szirom


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## windnrock

Interesting discussion. Beyond forgiveness for screwing up, applying physics for certain conditions or simply pleasure to the eye, much depends on where you go and what you will face. No boat is perfect for every condition. My Bristol 41.1 gives us good usable interior room, a pleasing appearance (to me) and some characteristics that keep her pretty dry. The freeboard at the bow is close to 4 1/2' while tapering to about 3' at the stern. In heavy weather she stays incredibly dry. We make choices with compromises on virtually everything. Safety, cost, convenience and form all play a part. For us vessel size was driven by capacity/storage and sail plan. The fact she is, in our eyes, a beautiful boat didn't hurt! With a centerboard that gives us about 11' up wind if we need it, the windage is not a big issue. The fact that the bow cleaves large waves like a knife does make a real difference.


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## krisscross

Sail444 said:


> I would recommend low freeboard, for offshore cruising. Less windage, and presents a *smaller footprint for beam seas*.


Interesting point. Thank you, Steve.
Anyone can elaborate on how it looks in practical heavy weather situations?


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## travlin-easy

Sail444 said:


> I would recommend low freeboard, for offshore cruising. Less windage, and presents a smaller footprint for beam seas.
> 
> Steve
> OysterYachting.com


So you are essentially saying that smaller footprint is better because a beam sea can wash over the boat and fill the cockpit? Really doesn't make a lot of sense to me. Less hull windage on a beam reach - I don't really see a benefit there either. I've only been sailing 8 years, maybe there's something I need to learn about low V/S high freeboard.

Gary


----------



## tdw

bobperry said:


> If you are out there is 8' breaking seas 6" more or less freeboard will not mean the difference between being wet or dry. High freeboard provides volume and that's about it. I can think of nothing else to say good about it.


Valid point BP though the disadvantage of low freeboard probably more obvious is more placid conditions. Friends of ours took a classic 1950s vintage Sparkman and Stevens low freeboard sloop across the Tasman to New Zealand and they did say the spray eventually wore them down.

I guess though we need to define high v low. I think of our girl (Malo39) as being high freeboard but compared to latest generation of production boats she is moderate at best. Nonetheless in 30 - 40 knots, moderate swell, fair bit of flying spray we stay quite dry, in cruising setup anyway.

No argument as to which looks best.


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## windnrock

I have raced J24s at sea with little freeboard to speak of and found it, at times, to be unpleasant being constantly awash. My current boat provides room, protection and performance. I have found comfort and stability to be a safer, less wearing environment. So what is "too much" freeboard and in what circumstance? I suspect the "proper" freeboard is the one you have on your current boat! Given the varied circumstances we face, a good compromise is, do you have enough for you most of the time?


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## bobperry

Womby makes a good point. The definition of high freeboard has changed dramatically over the years. High freeboard, or what I would call "high freeboard" seems to be the norm in modern production models. But of course, they are all about volume first. Race oriented models still favor what I would call low freeboard. I think what we think of as "normal" freeboard today would have been considered high freeboard in 1962. Makes me cringe when I wonder how high it will be in 2020!

Here is m y plan:
Because I get three new design to review every month from SAILING Magazine I am going to start tracking freeboard as a function of LOA. I don't know what this will get me but it will be fun and in a few months I'll have a seat othe pants feel for some real numbers and not just guesses.
I thin what I'll do is average freeboard at ste, tip and corner of transom and take that as a percentage of LOA.

I'll set aside some time tomorrow to look at six new boats and then I will report back. If anyone else wants to do the same thing we can combine results. Just do your best to be accurate. We must avoid sillyness at all costs. And remember you do not need scale drawings. You do need drawings, a simple sail plan would work, but you can pick any scale you like. The ratio will be the same. We can do a team project. We want old boats too. If the boat is old a year for the design would be helpful.

Field trip!


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## bobperry

OK Team I have some results:

EAGLE 54, Hoek design long, low and lean freeboard 7.3% of LOA
REDLINE 41 Mark Mills IRC racer freeboard 11% of LOA
Hanse 445 Mom and Pop type Euro cruiser freeboard 11% of LOA

That's at least a start. We have a boat that appears to have low freeboard at 7.3% and two boats with what I'd call moderately high freeboard at 11%.

Just did the prior months three boats:

Bavaria 51 a Farr design Mom and Pop style freeboard 9.8% of LOA
Dufour 410 anoher Mom and Pop cruiser freeboard 11.9%
Jeanneau Sun Odyssey 342 slick looking cruiser freeboard 12.5% 

So now our range is 7.3% of LOA to 12.5% of LOA.


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## Alex W

bobperry said:


> OK Team I have some results:
> 
> EAGLE 54, Hoek design long, low and lean freeboard 7.3% of LOA
> REDLINE 41 Mark Mills IRC racer freeboard 11% of LOA
> Hanse 445 Mom and Pop type Euro cruiser freeboard 11% of LOA
> 
> That's at least a start. We have a boat that appears to have low freeboard at 7.3% and two boats with what I'd call moderately high freeboard at 11%.


A few more from the calculations I did this morning in smaller boat sizes:
Catalina 36 MK2: 9.6%
C&C 35: 8%
Benetaeu 361: 11%
Pearson 28-2: 10%
Yankee 30: 9.5%
J/29: 9%


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## Minnesail

bobperry said:


> I think what we think of as "normal" freeboard today would have been considered high freeboard in 1962. Makes me cringe when I wonder how high it will be in 2020!


Presenting the 2020 Hunter 40:


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## GeorgeB

For those of us who want to play along at home... Do you measure freeboard from the shearline to the waterline and do you do it at the mast or do you take an average (like measurements at bow, stern, admidships and divide by 3).


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## Alex W

I'm doing it at the cockpit winches, from gunwale to waterline, using the best line drawing of the boat that I can find. So everything is a bit approximate.

I'm using the cockpit winches because that is normally where lifeline gates are setup, but you could pick any point. I don't know what Bob Perry picked.


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## bobperry

I just took freeboard right at the stem, under the anchor roller. Aft I took it right at the transom corner. I used a measured LOA. I consider the "sheer" at the top of the molded hull. There will be exceptions but we can caucus and factor those in. We may have to issue chits of non compliance. Alex can give a chit. I don't give a chit.

I suppose one freeboard amidships would be close to an average.

What is looks like to me is that today's "moderate" average freeboard is 10% of LOA. That's an easy benchmark to remember. Maybe we can fine tune as we go. I'd love to see more boats of the C&C 35 vintage that Alex measured.

I need a number for FRANCI LEE, Valiant 40, Cal 40, Bermuda 40. Columbia 26. Ericson 41.


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## ctl411

I would measure my gulfstar 50 but too much snow. Where are you finding line drawings to get the numbers from?


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## bobperry

ct:
I get a pile of drawings each month from SAILING for my reviews. I also have a drafting lamp that has a 4" dia. magnifying glass in the middle so I can do some close tolerance measuring of small drawings. I use an "Armstrong Tenths" scale. Everyone should have three of these. Why three? Because your friends will try to steal it. Every time someone left my office staff I would lose an Armstrong Tenths scale. It measures feet and tenths of feet, almost metric but not quite.

I am a fount, font, faunt, kfaunt of totally useless information.


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## ctl411

Bob what do you use to set the scale mast height, loa, something else?


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## Alex W

I just do an image search for the boat. This is the best that I found for your Gulfstar:
http://www.dreameryachtcharters.com/images/layout_big.jpg

I use Gimp (free Photoshop-like tool) for doing the measurements. There is a measuring tool that will let you measure the horizontal/vertical distance between any two points. On my straightened out version of that drawing I'm getting 1411 pixels LOA, 162 pixels draft. I divide that by the same measurements in inches (600 LOA, 66 draft) to figure out the pixels per inch. Since this drawing isn't great there is a little discrepency, I'm getting 2.34 pixels per inch for LOA, 2.45 for draft.

Then I measure the freeboard in pixels and divide by those numbers to pick a height. On your boat that is giving me 38 to 40" freeboard under the winches. I'd probably report 39".

For boats that I really care about like my Pearson 28-2 I measure multiple drawings to see which one appears to be most accurate. I did this at a number of my points on my boat because I want to compare drawing freeboard and actual freeboard to estimate my boat's real displacement.

The hardest part is getting good drawings. Owner's of S&S boats have the best luck, S&S has posted fairly high resolution drawings of many popular boats that they've designed to their blog. Most of us own boats from companies that are no longer in business (like Pearson) and have to make do with the best drawings that one can find on image search.


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## bobperry

411
It doesn't matter what scale you use. You just need some "units".
They don't have to relate to any real scale. They have to relate to each other.

So,,,,you have a drawing of a boat. Take out your ruler and measure the length. Be a dear and convert it to decimals please. Now measure the bow freeboard. The number you get will have nothing to do with the real bow height. IT"S ALL REALATIVE

Now take you bow freeboard number and add it to your stern freeboard number and then divide by 2. That will give you the average freeboard.
Now divide this number by the LOA in the units you have chosen.

I'd love to put my arms around your shoulders and show you how simple this is. I'm a classic Dad and very good at showing his kids how the world works.

I have a 16 year old coming from Panama to stay at the shack for two weeks. I have never met him. He wants to be a yacht designer. He will need to take his SAT test while he is here. It will be a lot of fun to have a kid here that needs me.


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## Alex W

Here are the raw numbers from two drawings for my Pearson 28-2 that show points that I've found useful for setting scale:

color drawing pixels	inches	ratio
draft 88	58	1.517241379
LWL 437	292.5	1.494017094
LOA 504	341.5	1.475841874
E 190	129	1.472868217
transom WL 5	3.355704698	
bow WL 69	46.30872483	
stern pulplit WL 60	40.26845638	

b&w drawing pixels	inches	ratio
draft 80	58	1.379310345
LWL 398	292.5	1.360683761
LOA 451	341.5	1.320644217
E 173	129	1.341085271
transom WL 4	2.941176471	1.36
bow WL 63	46.32352941	
stern puplit WL 55	40.44117647	

I feel pretty good about these numbers since both drawings line up pretty well (except for transom WL).  However it is still all approximate. For freeboard measurements I'll be happy if I'm within 2".


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## TomMaine

bobperry said:


> 411
> It doesn't matter what scale you use. You just need some "units".
> They don't have to relate to any real scale. They have to relate to each other.
> 
> Now take you bow freeboard number and add it to your stern freeboard number and then divide by 2. That will give you the average freeboard.
> Now divide this number by the LOA in the units you have chosen.


This is fun, Bob. Will an older design with a strong sheer line and high bow throw things off?

Using the 2 points-bow/stern(19.5), I get 10+% But from the lowest point of freeboard(15), I get closer to 7+%.


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## JonEisberg

Cool experiment, Bob, I'll be following this one with interest...

However, in terms of any 'Real World' assessment, will you be taking into account that most cruising boats, by the time they're ready to head off for some extended cruising, have often been 'sunk' on their lines as much as several inches, and the 'actual' amount of freeboard lessened considerably?

I've added so much weight and tankage to my own boat, that when she's fully loaded, her true waterline now isn't remotely close to where Brit Chance first placed it...


----------



## chucklesR

Going to the original question, i.e. how does high freeboard affect sailing -

Without high freeboard I have no chance of adequate accommodations in a boat with LOA I can afford. 

As a cruiser that means zero chance of sailing, and that's how it affects me. 

As to looks, yep, I sail a wedding cake.


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## christyleigh

chucklesR said:


> As to looks, yep, I sail a wedding cake.


 Hey.... what's wrong with that ?? Sometimes the cake is the prettiest thing at the reception


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## bobperry

Jon:
No I won't take that into consideration. Too nebulous and can't be applied with any guaranteed consistancy. I'll just assume we are talking about boats loaded as most mom and pop boats are loaded for wekends anf short cruises. In my office that would be the DWL. 

How many inches do you think you are down Jon?

Tom:
Is that an Alden?
I wonder if we need to take three freeboards, bow, stern and low point, What do you think? We could make that a judgement call for boats with lots of spring.

I added two more boats this morning:

FRANCIS LEE 62, Perry custom, narrow DE freeboard 8.1% of LOA
Outbound 46, Schumacher design cruiser freeboard 8.9% of LOA


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## bobperry

The Euro boats I have been measuring have virtually not spring to their shweer at all. They are pretty much just strtaight lines. It's the floating box look.

But with a more traditional boat with lots of spring we should take three freeboards. I've been thinking on this. 

I'd like to get some numbers for some racy boats. Maybe a few J Boat models, a Pogo. I'll check my SAILING reviews and see what I can ciome up with.

Are we all on the same page now on this?


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## TomMaine

bobperry said:


> Tom:
> Is that an Alden?
> I wonder if we need to take three freeboards, bow, stern and low point, What do you think? We could make that a judgement call for boats with lots of spring.


It is, Bob. You're right, this spring is pronounced. The straight line added here, tells it all.

If I average the 3 freeboard points now, I come up with 9% freeboard. Seems high. Then again, maybe freeboard you 'see', doesn't tell the whole story ?

Could we add (?) to modify extra springy sheers?

Pull the simple straight line on all decks and get our 'spring factor'? Easy to do.

The deepest area in this spring, is -5. That's severe I think.

How would you apply '5' to the freeboard formula to even out excessive spring(5)? On the other extreme, no spring(0)?

Nice of you to take that kid for couple weeks. He's lucky.


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## bobperry

Tom:
I think it best that we use three freeboards on all boats. I just did three more and I used three freeboards for each one. When I think the term "freeboard" I think the height of the hulll amidships, not just at the bow or stern.

Tayana 52 freeboard 8.05% of LOA
Valiant 40 freeboard 10.2% of LOA
Passport 40 freeboard 9.9% of LOA

Maybe I'll have the intern compile a list for us.

Come on Jeff, give us your boat's ratio.


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## RichH

The Golden Ratio .... used in many of the most 'eye pleasing' designs of humankind, such as the Parthenon, and other 'classic' buildings. 
Bob Perry 'shear lines', etc. seem to come close ;-)


----------



## TomMaine

bobperry said:


> Tom:
> I think it best that we use three freeboards on all boats. I just did three more and I used three freeboards for each one. When I think the term "freeboard" I think the height of the hulll amidships, not just at the bow or stern.
> 
> Tayana 52 freeboard 8.05% of LOA
> Valiant 40 freeboard 10.2% of LOA
> Passport 40 freeboard 9.9% of LOA
> 
> Maybe I'll have the intern compile a list for us.
> 
> Come on Jeff, give us your boat's ratio.


Got it. I took a 3rd measurement from amidships. 
16-13-23/3= 17.3 17.3/203=8.5%

For your list; 1961 Alden Challenger 8.5%


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## Jeff_H

bobperry said:


> Tom:
> I think it best that we use three freeboards on all boats. I just did three more and I used three freeboards for each one. When I think the term "freeboard" I think the height of the hulll amidships, not just at the bow or stern.
> 
> Tayana 52 freeboard 8.05% of LOA
> Valiant 40 freeboard 10.2% of LOA
> Passport 40 freeboard 9.9% of LOA
> 
> Maybe I'll have the intern compile a list for us.
> 
> Come on Jeff, give us your boat's ratio.


Bob,

I am not 100% clear on how you are calculating the ratio. Are you averaging the freeboard at the Bow, Stern and lowest point of the sheer, and then dividing by the length?

Jeff


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## krisscross

I just got 16.0% freeboard to LOA for Cape Dory 25 and 15.2% for Bayfield 25 (visually low freeboard boats) versus 18.6% for Hunter 25.5 (visually high freeboard boat). I think you can only compare boats of similar LOA using this formula.


----------



## bobperry

Jeff:
Yes. A simple freeboard at the stem, one at low point oif sheer and one at the corner of the transom. Then divide by LOA.

Kriss:
Those numbers seem very high. Did you use three freeboards? I think on boats like the CD and the Bayfield you need to measure the low point of the sheer also. That would bring the percentage down.

I'll check the Baba 30 and 40.

I think as the boats get longer the ratio will go down. But I still think we can use the same formula.

Tom:
Your boat and your family look beautiful.


----------



## krisscross

Yes, I did the average of 3 freeboard measurements. But to me it makes sense. The same 3 feet of freeboard looks (and calculates) very different on a 25 foot boat then on 35 foot boat.


----------



## bobperry

Boats like the Baba's present a wee problem in that they have that raised bulwark detail with the bulwark nipped off on the ends. But I always carry the true sheerline all the way through so I ignorred the bulwark and used the true sheer. So,,,,,the other way of doing it for the Baba's would be to project the bulwark height to the ends. That is most prob ably more representative of the true "freeboard".


So with projecting the bulwarks I get:
Baba 30 freeboard 13.2% of LOA
Baba 40 freeboard 10.8% of LOA

If I don't project bulwark I get:
Baba 30 11.6%
Baba 40 9.8%

Kriss:
I agree. That makes sense.


----------



## Faster

bobperry said:


> .......
> 
> Tom:
> Your boat and your family look beautiful.


Second that notion! 

..Very late to this discussion.. I like the ratio idea, it's enlightening.

Regarding 'high' freeboard what comes to mind is watching a Hunter 450 CC come into a dock with moderately low floats.. sailed by a couple, he's at the helm, she's at the rail with lines in hand. When it came time to 'jump' onto the dock (not 'across a gap' - he did a good job of coming alongside) she refused for fear of breaking an ankle... That's too high, esp in tidal waters where floating docks are the norm.


----------



## Minnesail

Back in post 17 I said my little Catalina 22 has a ratio of about .1 or 10%, but I was a) measuring only from the point of lowest freeboard and b) measuring slightly wrong.

Measuring again (this is from a photo of the boat floating, not a line drawing, I'm not sure if that's better or worse) I get:

Catalina 22 F/LOA
Bow: 13.3%
Mid: 11.8%
Stern: 10.7%
Average: 11.9%

Numerically this puts it in the middle of the pack, but visually I think it looks like a low freeboard boat. This confirms what Kriss said.


----------



## Jeff_H

So if I understand how you are calculating the ratio (average of the three heights divided by the length) my boat would have a ratio of 8.97%. Sorry about the crummy image quality. I actually wish that my boat had a few more inches of freeboard, and a slightly lower house.


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## bobperry

Nordic 44 freeboard 8.7% of LOA
AMATI Custom 40' Perry freeboard 9.75% of LOA


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## Alex W

Jeff_H said:


> I actually wish that my boat had a few more inches of freeboard, and a slightly lower house.


Do you wish it had the same overall standing room, with more of that allocated to freeboard? Or do you wish that it had additional freeboard and reduced standing room?

I've wondered some about this tradeoff of freeboard vs house height. If the house is the full length of the boat (as on many centercockpit boats) it seems like there would be very little functional difference. On a typical aft cockpit boat a taller house with lower freeboard seems like it gives you the standing height without the windage of making the freeboard higher across the whole boat.

Here is a measured image for my tubby little boat. % is higher then what I reported before because I'm doing Bob's averaging method. Since this appears to be a euro-inspired boat it doesn't have much shearline, but the bow does have more freeboard than the stern.


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## bobperry

ICON 65'9" Custom Perry racer/cruiser freeboard 7.43% of LOA

I think your boat's proportions are just dandy Jeff.


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## Alex W

Bob: Do you have good drawings for the Islander 28 handy? I do want to see a few more small boats, and that one is pretty similar to my Pearson in LOA, draft, displacement and PHRF. If you don't I can measure from drawings available online (or in your book if I go grab my copy from my neighbor).


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## outbound

Curious about this discussion of windage. Agree a flush deck not having the house so profile extends to the forepeak will have significantly more windage. But shouldn't we included the house and hard / soft dodger and (god forbid) enclosure as part of windage. In that case contribution of high freeboard to windage may be less then being discussed. Should we also account for the particulars of a given house. One would think those with slope to sides and front would have less effective windage then a plain box. Also the smoothness of the surfaces and depth of overhangs.. Also how far house extends forward and aft. Indented ports, tackle, pulpits, dorades, etc. must contribute to some degree. Agree with ratio below 9% my boat looks right but some feel that way about current crop of euro cruisers. Is this aspect of boat design overblown in terms of functional sailing importance. Even with my low freeboard boat we need a step when berthed. Jumping off is just do- able. Looks are preserved. Don't get me wrong I prefer moderate to low freeboard boats.


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## bobperry

Alex:
Islander 28 Perry cruiser/racer freeboard 11.7% of LOA
Aloha 26 Perry cruiser freeboard 12.5% of LOA
Mirage 25 Perry cruiser freeboard 13.5% of LOA

Out:
I have no idea. What I know is that I aim for the3 lowest freeboard that I can use given the requirements. I do not believe freeboard, within reason, creates a dry boat when spray flies and in Seattle freeboard won't protect you from the rain. Rating rules always credit you for freeboard and that tells me it's slow.


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## Alex W

Thanks Bob. It's good to get a balanced look at this across different boat sizes.

I sail on a few 30' boats that are in the 10% freeboard range and like them, but the 12% range does create a lot of useful interior volume.


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## socal c25

My little Coronado 25 has a fair amount of freeboard and a large cabin, the ride is fairly dry as there is a good bit of sheer, there is a bit of windage but it seems less than my old Catalina 30 which has high freeboard and a fairly low cabin.


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## bobperry

I don't have any drawings for my Cirrus 7.8 but at 26' I suspect I was pushing 12%.

Maybe when my intern arrives I'll have him plot a graph so we can see how the ratio changes with LOA. Over the weekeend I can compile what I have and post it unless someone else would like to do that.


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## Barquito

> Curious about this discussion of windage. Agree a flush deck not having the house so profile extends to the forepeak will have significantly more windage. But shouldn't we included the house and hard / soft dodger and (god forbid) enclosure as part of windage. In that case contribution of high freeboard to windage may be less then being discussed. Should we also account for the particulars of a given house. One would think those with slope to sides and front would have less effective windage then a plain box. Also the smoothness of the surfaces and depth of overhangs.. Also how far house extends forward and aft. Indented ports, tackle, pulpits, dorades, etc. must contribute to some degree. Agree with ratio below 9% my boat looks right but some feel that way about current crop of euro cruisers. Is this aspect of boat design overblown in terms of functional sailing importance. Even with my low freeboard boat we need a step when berthed. Jumping off is just do- able. Looks are preserved. Don't get me wrong I prefer moderate to low freeboard boats.


I agree. My boat has low freeboard, and a high house. What really creates the most windage is when I am leaning forward over the bow pulpit screaming, "I'm king of the world!"


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## bobperry

Barquy:
No problem. Just smear some salmon oil in your hair and slick it down. It will reduce the windage.


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## Minnesail

bobperry said:


> Barquy:
> No problem. Just smear some salmon oil in your hair and slick it down. It will reduce the windage.


And you'll smell nice for the ladies.


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## bobperry

Scoff!
Go ahead and scoff!
But I'm telling you at my age I am all about dating young women. And the salmon oil thing is killer.
They just dig around in your pockets looking for the bagel and the cream cheese.


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## socal c25

Youz guyz R crakin' me UP..... LOL


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## bobperry

Oh yeah babay. I can dance!


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## jak3b

Dont use farm raised salmon oil though, theyll think your a phony.


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## TomMaine

bobperry said:


> I need a number for FRANCI LEE, Valiant 40, Cal 40, Bermuda 40. Columbia 26. Ericson 41.


This may be the Block Island but I think it's the B40. Hope this internet line drawing image is true scale.

Bermuda 40 9.6%


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## bobperry

Tom:
That is higher than I would have guessed. But the bow is really high.


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## captain jack

krisscross said:


> I have a wide dinghy with low freeboard (Holder 14) and I sometimes sail like that in high winds. When hiked out on the rail I can see my dagger board starting to come out of the water.* That board is really the only thing keeping the dinghy from tipping over. *Then I know I have to ease out the main sheet to de-power the sail. Not sure if higher freeboard would have made much difference in that case.


that's a common myth. underwater foils do not resist heel/capsize. ballast does. underwater foils resist leeway by creating lift in opposition to the lift created by the sails. in fact, underwater foils increase heeling. deep skinny fins cause worse heeling than do long shallow keels because the generate lift at a point more distant from the pivot point of the boat. when hiked on the rail of your dighy, it is you, the moveable ballast, that keeps it from tipping over.


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## krisscross

captain jack said:


> that's a common myth. underwater foils do not resist heel/capsize. ballast does. underwater foils resist leeway by creating lift in opposition to the lift created by the sails. in fact, underwater foils increase heeling. deep skinny fins cause worse heeling than do long shallow keels because the generate lift at a point more distant from the pivot point of the boat. when hiked on the rail of your dighy, it is you, the moveable ballast, that keeps it from tipping over.


I understand what you are saying but I'm not sure that you are 100% correct based on my direct experiences. As soon as the daggerboard comes out of the water even partially (I have extended the board to improve upwind performance) the dinghy tips over, even when two of us are hiked out on the rail. The other daggerboard stability experience I have is from windsurfing and standup paddling (I use the same big board to do both). The daggerboard improves side to side stability to an incredible degree, which is felt directly by any windsurfer and paddler using boards equipped with one (you can fold or deploy the dagger at will). That is even more pronounced when moving, and the faster you move the more stability is created by the daggerboard. Not sure what the theory behind it might be, but I have no doubt that it works that way. My board (Fanatic 370) has a big daggerboard as well as a much smaller skeg.


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## baboon

My experience with windsurfing and dingy sailing is the daggerboard dampens healing and roll, but does not keep you upright. One the board is partly out of the water control is reduced and the boat gets twitchy, but can still be sailed.


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## captain jack

krisscross said:


> I understand what you are saying but I'm not sure that you are 100% correct based on my direct experiences. As soon as the daggerboard comes out of the water even partially (I have extended the board to improve upwind performance) the dinghy tips over, even when two of us are hiked out on the rail. The other daggerboard stability experience I have is from windsurfing and standup paddling (I use the same big board to do both). The daggerboard improves side to side stability to an incredible degree, which is felt directly by any windsurfer and paddler using boards equipped with one (you can fold or deploy the dagger at will). That is even more pronounced when moving, and the faster you move the more stability is created by the daggerboard. Not sure what the theory behind it might be, but I have no doubt that it works that way. My board (Fanatic 370) has a big daggerboard as well as a much smaller skeg.


i don't want to get in a huge debate about it but, i think you don't quite understand what is going on when you are hiked out. it's funny, Jim Michalak has an article, on the effects of hiking, on his site. it just came out.

first, i would point out that the underwater foil is best when it's area is around 4% of the sail area. much more than that and it creates more drag without improving efficiency. making the daggerboard bigger isn't necessarily a good idea.

your dinghy is different than a fixed keel ballasted boat. a ballasted fixed keel boat ( BFKB from now on  ) gets it's stability mostly from the ballast. it has less initial stability than your dighy, which gets it's initial stability from it's hull form. so, the BFKB heels easily, in the beginning. however, as it heels, the fin ( with it's ballast weight ) begins to angle outwards. as this happens, the weight moves, from being directly under the centerline pivot point of the boat, to being farther away from that centerline. it's like having a 20 pound weight in your hand. held in your fist at your side, it seems to weigh very little. as you raise your arm from your side ( keeping your arm straight ) and, as your fist gets farther from your body, the weight begins to feel heavier.

this is what is called the 'righting arm', in sailboat design. the longer the righting arm, the greater the force is to resist heel/capsize. in other words, the farther the ballasting weight is from the centerline, the more it resists the force of the wind on your sails.

so, on our BFKB, the more the boat heels, the harder it is for the wind to push it over. at 90 degrees of heel, the ballast has maximum effect.

your dinghy isn't this way. dinghies use the shape of the hull to make them much more stable* up to a certain degree of heel*. that is: they have a lot of initial stability. they don't have a fixed ballast. they have skipper ( and crew ) that act as moveable ballast. moveable ballast is very effective at low degrees of heel. all of the ballast is as far as it can get from the centerline.

however, hiking/moveable ballast works the opposite of the fixed ballast in our BFKB. if you looked at your dinghy from the front, as you sailed, you would notice that you, the ballast, move closer to the centerline of the boat as the boat heels. thus, the moveable ballast of you and your hiked crew becomes less effective as heel increases.

in a dinghy, if your daggerboard/centerboard is half out of the water, you are heeled way far over. most dinghies are meant for far less heel. heel too far and it doesn't matter how much weight you have on your rail, you are going to go over.

i am not sure what you mean by side to side stability, so i can't comment on the paddleboat. but your experience with the dinghy and crew hiked out to the side proves the point. once the dighy hits a certain point of heel, moveable ballast becomes ineffective and the boat is going to go over if you don't spill wind. that has nothing at all to do with your daggerboard. it has to do with the righting arm of the ballast.

as far as the daggerboard having more affect as it goes faster, that is true. they do. at 0 MPH, the underwater foil can not really create lift ( which is how it works ). the boat must be moving, so water passes over the foil, for it to create lift.

but your underwater foil creates lift in opposition to that of the sail. so, if the sail is pushing to port, the daggerboard is pushing to starboard. if it didn't work this way, your boat could not sail up wind. it would blow down wind. however, both of these forces create heel. think about it. the bottim of your boat, on the water is the pivot point. the lift of the sail(s) and the foil work together, around that pivot point, to rotate your boat around this pivot point. that creates heel. it doesn't resist it. and, logically, with a long skinny keel, the foil is creating lift at a point farther from the boat than it is with a longer, shallower keel. that distance the lift is from the pivot point cooresponds to the righting arm, only it works to tip you. so, the farther lift is created from the pivot, the greater the ....wronging arm, shalle we say...making the heeling force greater. tall, skinny sail rigs with deep skinny fins really heel a lot quicker and easier than short rigs with long shallow keels.

from personal experience, i can vouch for the fact that a deep skinny fin creates more heel than a long shallow fin. i converted my daggerboard dinghy to a long shallow keel. now, it tracks far better; not being easily forced off course by sudden gusts or wakes or chop. it also heels less, in a given wind, and it heels less violently. it used to be fairly tender but i have sailed through some serious weather with it as a long keel dinghy and it is noticably less tender than it used to be.

sorry for the long post but....it's physics. 

check out Jim's site and read his most recent article, it will help you understand:

Jim Michalak's Boat Designs/The Index

not only did he recently do an article on the effects of hiking but he has, in the past, done a lot of articles relating to the physics of sailing and, even if you ignore the math because math is complicated, his explanations are pretty easy to understand. he gives diagrams and stuff. i'd recommend his site to anyone interested in sailing.


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## outbound

Simply put the vector generated by a foil ( keel,centerboard , daggerboard ) is perpendicular to the foil. When heeled some of that vector is upward increasing risk of broach. Only some is resisting slide to leeward. One of the reasons vmg is better if boat sailed flat. Putting the rail down is slow.
Both down portion of sail vector and up portion of under water foil only resisted by form stability or righting arm of ballast or both.


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## TomMaine

JonEisberg said:


> Cool experiment, Bob, I'll be following this one with interest...
> 
> However, in terms of any 'Real World' assessment, will you be taking into account that most cruising boats, by the time they're ready to head off for some extended cruising, have often been 'sunk' on their lines as much as several inches, and the 'actual' amount of freeboard lessened considerably?
> 
> I've added so much weight and tankage to my own boat, that when she's fully loaded, her true waterline now isn't remotely close to where Brit Chance first placed it...


I found a line drawing of the 30-30 from the Allied website, Jon. Then I took you photo of CHANCY and dragged it to the same LOA while keeping it constrained. Not too scientific, but the lines look like duplicates.

I added the same unit of freeboard amidships-19. Sure enough, there's your old topsides paint line. CHANCY lines out at 9.2% while the orignal drawing shows 12.5%

I'm not sure the value of this experiment yet(I think Bob is working on it), but I think you've used up your 'freeboard allowance' on CHANCY.


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## krisscross

Captain Jack, thanks for the explanation. In my 15 years of sailing that dinghy I tipped it over only a couple of times, mostly intentionally (winds over 25 mph) as I wanted to see where it's tipping point is.
By side to side stability of the board I meant roll - it is something very noticeable for anybody on the board. Daggerboard down reduces roll very well and often makes a difference between being able to stay on the board and being in the drink all the time. I paddle my SUP on the ocean quite a bit and when there a waves daggerboard dampens the side to side roll. and the faster you move the more stable it is. Same with windsurfing. Daggerboard makes it much easier to get going without spilling every few seconds.


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## christian.hess

a long rudder helps too

we played with rudders on an old 505 or 470 cant remeber since it came with a broken one at the club I was at...the difference was very noticeable goiong from "stock" size to longer and skinnier

same with daggerboards...its fun to play on dinghies the point is that if you want to race you have to stick to the rules...

for having fun you can make dinghies massively better performers then they are stock

rigging hiking straps...longer daggerboards...even add rigging masts on standing masts like lasers...poles, bigger sails etc...

all fun


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## christian.hess

TomMaine said:


> I found a line drawing of the 30-30 from the Allied website, Jon. Then I took you photo of CHANCY and dragged it to the same LOA while keeping it constrained. Not too scientific, but the lines look like duplicates.
> 
> I added the same unit of freeboard amidships-19. Sure enough, there's your old topsides paint line. CHANCY lines out at 9.2% while the orignal drawing shows 12.5%
> 
> I'm not sure the value of this experiment yet(I think Bob is working on it), but I think you've used up your 'freeboard allowance' on CHANCY.


man thats almost 4 percent!

my antifouling on my islander 36 was around 5-6 inches above standard waterline

I have no idea what the po was carrying aboard but I kept it there since Ill be cruising too

can anyone say what the benefit would be to being lower in the water and increasing waterline length versus extra weight(displacement)

i.e are you in fact slowing the boat down so much? even in heay winds for example where extra displacement and a deeper keel and righting movement are helpful?

or is it simply that carrying too much load is always always bad

Im not talking about water balllast and moveable ballast but simply a cruising boat set up for long distance sailing with around 20% stowage(per boats displacement)

versus a bare boat...

will a bare boat always perform better, even in heavy offshore sailing scenarios with appropriate reefing and sails or will a ladden boat improve in certain scenarios?

I always felt differences when needing to stock up in port and after leaving port, but I rememember being more stable when the crap hit the fan and the boat was cruise ready

just my thoughts here

BOB?

ps im not on my boat right now so does anyone have the freeboard specs for a stock ISLANDER 36?

thanks


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## TomMaine

christian.hess said:


> can anyone say what the benefit would be to being lower in the water and increasing waterline length versus extra weight(displacement)
> 
> i.e are you in fact slowing the boat down so much? even in heay winds for example where extra displacement and a deeper keel and righting movement are helpful?
> 
> or is it simply that carrying too much load is always always bad
> 
> Im not talking about water balllast and moveable ballast but simply a cruising boat set up for long distance sailing with around 20% stowage(per boats displacement)
> 
> versus a bare boat...
> 
> will a bare boat always perform better, even in heavy offshore sailing scenarios with appropriate reefing and sails or will a ladden boat improve in certain scenarios?
> 
> I always felt differences when needing to stock up in port and after leaving port, but I rememember being more stable when the crap hit the fan and the boat was cruise ready
> 
> just my thoughts here
> 
> BOB?
> 
> ps im not on my boat right now so does anyone have the freeboard specs for a stock ISLANDER 36?
> 
> thanks


I read Bob's book, so I know what he's going to say.

"Weight is always the enemy on a sailboat, unless it's on the bottom of your keel. Anywhere else, it's the enemy," a quote from Bob.

I took that simple fact away from his book and applied it to my own boat. I'm a coastal cruiser so that's doable. And even though I sail an old boat that doesn't compare to the new high performance designs Bob is usually engaged in, these days, I know I can make a difference in how well my boat sails, especially in light air, by keeping it light.

It's my guess that there's quite a difference in performance between a boat loaded to 10% of it's displacement, and one loaded 20%. I know I'm under 10%


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## bobperry

I'm hung over. I can't think about numbers right now.


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## mgiguere

Enjoyed reading all the posts on this topic by obviously some very learned people. I've had my 1967 S&S 37 for almost 30 years and it is just plain a great sailing boat. Have been off shore between Annapolis and Maine a number of times and in all kinds of weather and it's not any wetter than any other boat I've been on. But I would definitely like to calculate the freeboard indicator some time...my guess is that it's below 10%. If interested in seeing this rather uncommon boat you can check out some pics at the link below. (since I don't know how to post them on sailnet.)

https://plus.google.com/u/0/photos/100556647302377781038/albums/5715748141482903521

Moe
Apache 37

Moe


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## captain jack

christian.hess said:


> man thats almost 4 percent!
> 
> my antifouling on my islander 36 was around 5-6 inches above standard waterline
> 
> I have no idea what the po was carrying aboard but I kept it there since Ill be cruising too
> 
> can anyone say what the benefit would be to being lower in the water and increasing waterline length versus extra weight(displacement)
> 
> i.e are you in fact slowing the boat down so much? even in heay winds for example where extra displacement and a deeper keel and righting movement are helpful?
> 
> or is it simply that carrying too much load is always always bad
> 
> Im not talking about water balllast and moveable ballast but simply a cruising boat set up for long distance sailing with around 20% stowage(per boats displacement)
> 
> versus a bare boat...
> 
> will a bare boat always perform better, even in heavy offshore sailing scenarios with appropriate reefing and sails or will a ladden boat improve in certain scenarios?
> 
> I always felt differences when needing to stock up in port and after leaving port, but I rememember being more stable when the crap hit the fan and the boat was cruise ready
> 
> just my thoughts here
> 
> BOB?
> 
> ps im not on my boat right now so does anyone have the freeboard specs for a stock ISLANDER 36?
> 
> thanks


moast cruising boats are designed with half of the full load cpacity as the guide. kind of a compromise between the extremes. boats almpost always sail best on their intended lines. for instance, if a boat is meant to be sailed as flat as possible, that will be how it sails best. to answer your question, if you always sail overloaded, it's bound to hurt performance. longer waterline means higher hull speed but at a cost of drag. longer waterline affects maximum speed but drag affects acceleration and the power needed to reach hull speed. it's hard to tell how the extra load really affects the performance, outside of experience with it. i think it's different now that engineers use computer simulations to predict performance but, in the past, most boat enhineers could only do a close guestimation on actual performance until the design was tested on the water. let's face it, things like sail plan balance are based on theoretical models; not hard facts.

as has been noted, weight above the waterline is never good for a sailboat.


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## christian.hess

yeah its that experience Im aiming to gain information from say a naval architect....I agree with you completely its not that I dont know that overloading is bad and hurts but 

extra ballast does help in some cases and most gear at least the way I stow it is close to waterline

I hate for example dinghies on deck, or davits(even though my boat has them) fuel containers on deck etc...decks are clean on my boats...

anywhoo

just wondering...

thanks though


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## christian.hess

TomMaine said:


> I read Bob's book, so I know what he's going to say.
> 
> "Weight is always the enemy on a sailboat, unless it's on the bottom of your keel. Anywhere else, it's the enemy," a quote from Bob.
> 
> I took that simple fact away from his book and applied it to my own boat. I'm a coastal cruiser so that's doable. And even though I sail an old boat that doesn't compare to the new high performance designs Bob is usually engaged in, these days, I know I can make a difference in how well my boat sails, especially in light air, by keeping it light.
> 
> It's my guess that there's quite a difference in performance between a boat loaded to 10% of it's displacement, and one loaded 20%. I know I'm under 10%


what if your weight is at or near waterline?

modern boats have moveable water ballast that for sure is not at the keel! jajaa

not playing devils advocate, I agree with everything being said

im guessing my boat was at 20 percent load when looking at the lines the po had made...right now Im "under" weight ,the original waterline or better put Im an inch above original waterline since Im engineless and very bare hull....lots of woodwork eliminated...no lifelines or sails back on etc...

but the engine was around 400lbs...

Ill be using an outboard for on off mooring and out the chanel..so I will have improved handling in that sense...lighter if you will, slightly.

but seriously...does weight at waterline...balanced side to side...like water ballast in ocean racers...could it improve at least motion at sea and stabilty over say a long 1000-2000mile passage?

we kind of did this on the boats I sailed on across the pacific, most heavy items were stowed to windward...and aft a bit since we where in the trades mostly broad reaching or close to ddw.

we wre just playing around but like with surfing ultralights your weight is all the way back over the rudder...and that helps as we all know...keeps things where they should

rudder down! ajajaja


----------



## captain jack

christian.hess said:


> what if your weight is at or near waterline?
> 
> modern boats have moveable water ballast that for sure is not at the keel! jajaa
> 
> not playing devils advocate, I agree with everything being said
> 
> im guessing my boat was at 20 percent load when looking at the lines the po had made...right now Im "under" weight ,the original waterline or better put Im an inch above original waterline since Im engineless and very bare hull....lots of woodwork eliminated...no lifelines or sails back on etc...
> 
> but the engine was around 400lbs...
> 
> Ill be using an outboard for on off mooring and out the chanel..so I will have improved handling in that sense...lighter if you will, slightly.
> 
> but seriously...does weight at waterline...balanced side to side...like water ballast in ocean racers...could it improve at least motion at sea and stabilty over say a long 1000-2000mile passage?
> 
> we kind of did this on the boats I sailed on across the pacific, most heavy items were stowed to windward...and aft a bit since we where in the trades mostly broad reaching or close to ddw.
> 
> we wre just playing around but like with surfing ultralights your weight is all the way back over the rudder...and that helps as we all know...keeps things where they should
> 
> rudder down! ajajaja


i can give you some insight about this. first, any weight above the waterline counts as a negative. it raises the CG. keeping it as low as possible, and even using it as moveable ballast, does help, though.

the way it used to be figured was to add the weight up, based on location ( high or low in relation to the waterline ). then it is averaged up and a center of weight would be found. i am not including the ballast with that weight.

once you fiond that number, you would contrast that to the ballast. you have to find a center of weight for the ballast, too.

but that just balances the weight. you then have to figure out the push of the wind on your sails. usually you choose the highest wind speed before you reef, to use for this calculation. so that, at that speed, say 15kt, the wind has X amount of PSI. you multiply that times your sail area. then you have to know the center of effort for your sail plan. because there is a leverage factor that your ballast must equal out (the 'remaining' ballast after you subtract the above the waterline weight from the below the waterline weight).

then, you compare the 'remaining' ballast ( the righting arm ) with the force of the sails. it must zero out, at least, to make sure your boat has the right stability.

that's the first thing. having a lot of weight above the waterline definately changes the stability of your boat. next, is figuring out if you need to add more sail area to drive all that extra weight and drag.


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## captain jack

ok Christian. here are a few links for you. some directly relating to your question and some indirectly relating. all i think you will find interesting.

http://web.archive.org/web/20050309032453/http://marina.fortunecity.com/breakwater/274/1999/1101/Index.htm#CENTER OF GRAVITY

this first one is figuring center of gravity which is what i was talking about above.

Jim Michalak's Boat Designs/The Index

this one is on sail area math

http://www.jimsboats.com/15may11.htm 
http://www.jimsboats.com/1jun11.htm
sail sizing 1 and 2

http://www.jimsboats.com/1oct12.htm
http://www.jimsboats.com/15nov12.htm
http://www.jimsboats.com/1dec12.htm
figuring sails 1, 2, an 3

http://www.jimsboats.com/1apr11.htm
displacement

http://web.archive.org/web/20050309032821/http://marina.fortunecity.com/breakwater/274/1998/0228/index.htm#Water
water ballast


----------



## JonEisberg

TomMaine said:


> I found a line drawing of the 30-30 from the Allied website, Jon. Then I took you photo of CHANCY and dragged it to the same LOA while keeping it constrained. Not too scientific, but the lines look like duplicates.
> 
> I added the same unit of freeboard amidships-19. Sure enough, there's your old topsides paint line. CHANCY lines out at 9.2% while the orignal drawing shows 12.5%
> 
> I'm not sure the value of this experiment yet(I think Bob is working on it), but I think you've used up your 'freeboard allowance' on CHANCY.


Thanks for that, Tom - very interesting... You are no doubt correct, I have definitely used up all of my "freeboard allowance" on my boat... 

Not by as much as one might think, however. The photo you've used as a reference is somewhat deceptive, and the 'waterline' defined by the placement of the boot stripe is considerably higher than the true immersed waterline...

I've always liked the look of a high bootstripe, and a few inches of bottom paint showing above the water... It's one of the better ways to reduce the apparent height of the freeboard, adds length to the look of the boat... Also, with a painted hull like mine, paints like Awlgrip and Alexseal don't like long term immersion, I'd rather have my topsides floating well free and clear of the water when the boat is at rest...

When I first bought my boat, the bootstripe was a mess, very uneven, higher on one side than the other... I re-marked her actual waterline with the boat light before hauling her and redoing the bottom for the first time... And, while I have raised the waterline by a considerable degree over time, I'm pretty sure that I've in reality only 'sunk' the boat with the addition of all the weight and gear by 3, maybe 4 inches, at the most... Not an inconsiderable amount, by any means, but I don't feel it's done much to degrade her performance... And, if anything, I think she has a noticeably more seakindly and comfortable motion, now that she's down on her lines a bit...

I believe the designed waterline was never too far below the top of the rudder. Also, you can see a noticeable turn of the bilge just a bit below the current boot top, Bob would know what that reflects exactly, but I'm pretty sure it's relative to the IOR rule, and the measurement taken at the waterline...


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## captain jack

is your transom actually under the water, as it appears in that pic? i know that is not good for performance.


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## miatapaul

bobperry said:


> Scoff!
> Go ahead and scoff!
> But I'm telling you at my age I am all about dating young women. And the salmon oil thing is killer.
> They just dig around in your pockets looking for the bagel and the cream cheese.





bobperry said:


> I'm hung over. I can't think about numbers right now.


Yea, that is what happens when you party with the younger crowd. As we get older it is harder to keep up! I must say you look a lot less grumpy with her!


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## JonEisberg

captain jack said:


> is your transom actually under the water, as it appears in that pic? i know that is not good for performance.


At hull speed, I'm sure several square inches of it are immersed, no doubt...

I'm not too worried about the performance hit, you're gonna have to accept some compromises when turning an old IOR design into a cruising boat...


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## captain jack

JonEisberg said:


> At hull speed, I'm sure several square inches of it are immersed, no doubt...
> 
> I'm not too worried about the performance hit, you're gonna have to accept some compromises when turning an old IOR design into a cruising boat...


very true


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## bobperry

I have been recovering from my night of merryment (wanna hear me sing Poncho and Lefty?) so I have not been following carefully. But I'll throw this in. Most mom and pop type cruiers /racers have a VCG at 4" above to 4" below the DWL. To load your boat to the point that there would be serious stability issues would be difficult. And remember, Righting Moment is Righting arm times Displ. So if you can load your boat without raising the VCG, extra displ will increase Rm.
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

And do not pay attention to Jon. He spends his days sitting in a folding chair on the dock poking his BBQ.


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## travlin-easy

Yeah, I wanna hear Pancho and Lefty - I used to perform that song.  That's an old Willie Nelson song that was pretty popular at one time.

Gary


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## Tayana42

Bob, I fell in love with your Tayana 37 but ended up buying a Harris designed Tayana V42. Now I've loved her for 13 years. High sided does give us comfortable volume, headroom, and a dry ride. You said Alberg never designed an ugly boat. I've never seen a Robert Perry design that wasn't beautiful.


Sent from my iPad using Tapatalk


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## Alex W

I measured my boat yesterday (without referencing the measurements that I'd taken off of the images) and finally sat down tonight to compare them. This was instigated by this thread and another where I was asking Bob Perry about measuring boat displacement on Sailing Anarchy.

My measurements are within 1/2" (about the level of precision that I can get from the tape measure or images of my boat), so I'll just say my boat is floating pretty close to it's lines. On Sailing Anarchy it sounded like it would take about 700-800lbs to sink my boat 1".

My freeboard was measured with the water tank empty, fuel tank 2/3rds full, 1 more battery than stock, and a full set of kitchen dishes and some about 40lbs tools and parts. I removed one heavy piece of stock equipment, the water heater. Cruising weight for us is probably about 500lbs heavier (200lbs of which is water, since our water tank is 25 gallons).

Has anyone else measured their boat in person after measuring their drawings for this thread? How did it compare?


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## captain jack

bobperry said:


> I have been recovering from my night of merryment (wanna hear me sing Poncho and Lefty?) so I have not been following carefully. But I'll throw this in. Most mom and pop type cruiers /racers have a VCG at 4" above to 4" below the DWL. To load your boat to the point that there would be serious stability issues would be difficult. And remember, Righting Moment is Righting arm times Displ. So* if you can load your boat without raising the VCG*, extra displ will increase Rm.
> ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
> 
> And do not pay attention to Jon. He spends his days sitting in a folding chair on the dock poking his BBQ.


very good point but easier said than done. deeper ballast has a greater righting arm. if, say, our boat has most of it's ballast in a bulb at the end of it's fin, any weight placed above the bulb will alter the VCG and, therefore, alter the righting arm. in most cruising boats, the ballast is not conveniently placed in a spot at the extreme end of the fin. it's spread over a portion of the fin. plus, many, if not most, modern cruising boats don't have a ton of storage space below the waterline. that means that most, if not all, of the extra load of the fully stocked boat will be above the waterline and, therefore, detrimental to the VCG...even though the boat sits lower in the water when overloaded.

of course, in most ballasted boats, i doubt that reasonable overloading will cause a stability issue so bad that it will cause an actual capsize. however, ultimate stability in most ballasted keel boats includes the ability to be self righting. it is possible for enough weight to be placed high enough to hinder a vessel's self rigting ability. especially with the modern tendency towards very beamy cruisers.


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## TomMaine

JonEisberg said:


> I've always liked the look of a high bootstripe, and a few inches of bottom paint showing above the water... It's one of the better ways to reduce the apparent height of the freeboard, adds length to the look of the boat...
> 
> And, while I have raised the waterline by a considerable degree over time, I'm pretty sure that I've in reality only 'sunk' the boat with the addition of all the weight and gear by 3, maybe 4 inches, at the most... Not an inconsiderable amount, by any means, but I don't feel it's done much to degrade her performance... And, if anything, I think she has a noticeably more seakindly and comfortable motion, now that she's down on her lines a bit...
> 
> I believe the designed waterline was never too far below the top of the rudder. Also, you can see a noticeable turn of the bilge just a bit below the current boot top, Bob would know what that reflects exactly, but I'm pretty sure it's relative to the IOR rule, and the measurement taken at the waterline...


I think the raised waterline does look good on your boat compared the line drawing. And as you prove by how much sailing you do, your added weight doesn't kill sailing ability.

But I go the other way on added weight. It is a necessary evil, especially if you're cruising. I was in denial with my last boat and turned it into a poor all around sailer, with too much weight.

I've gone the other way now on 'seakindly' too. Seakindly 'feels',... 'loggy' to me. 

Case in point-If I fill my forward watertank, I lower the forward waterline a few inches. Not only is that slower(fact-weight), I can't see any benefit to slowing the bows motion down. So I only fill it if we're off for more than a week or so.

It's all relative but I now sense that the more hull I get out of the water, the more day to day sailing I'll do.

I don't know what this all means, but it's interesting.  For what it's worth, the line drawing on your boat appears that the rudder top is about 4"? out of the water.


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