# Centreboard vs keel



## Chucknuckle (Oct 16, 2018)

I realise this has probably been done to death, but I'd like to get the opinions of more experienced sailors than myself.

If you could choose between a centreboard or keel for the same boat, which would you choose and why? Most of my sailing will likely be short, trailered trips in our local lake system, but I also have desires to take her offshore for coastal cruising. I will be building this boat, not buying, so a consideration must be given to simplicity of design, reduced materials cost, ease of construction, etc.

The boat in question is a Grey Seal by Iain Oughtred:


----------



## capta (Jun 27, 2011)

We love our centerboard. We use it almost every day, at anchor and underway. At anchor, it minimizes roll in an anchorage and also underway, but it also can be used to reduce weather or lee helm by having it partially or all the way down.


----------



## TomMaine (Dec 21, 2010)

Chucknuckle said:


> I realise this has probably been done to death, but I'd like to get the opinions of more experienced sailors than myself.
> 
> If you could choose between a centreboard or keel for the same boat, which would you choose and why? Most of my sailing will likely be short, trailered trips in our local lake system, but I also have desires to take her offshore for coastal cruising. I will be building this boat, not buying, so a consideration must be given to simplicity of design, reduced materials cost, ease of construction, etc.
> 
> The boat in question is a Grey Seal by Iain Oughtred:


I would choose the centerboard boat. I like the ability to get into shallow water to anchor and even sail through. If the boat is intended to be trailerable then all the more the centerboard draft for increasing places you can haul and launch.

Ratings of the same boat with shoal vs deep keels allow about 3 to 5 seconds per mile. That's important to racers I suppose but has no relevance to me, a coastal sailor.

The Seal design, very beautiful, looks like a perfect keel centerboard. I doubt there is much performance difference between the two drafts.


----------



## denverd0n (Jun 20, 2008)

If you're going to be trailering the boat then centerboard. Absolutely.

The shallower draft simplifies trailer design, making for a less expensive trailer. It also makes it easier to get on and off the trailer, and opens up more ramps that you are able to use.

Having owned a number of trailer boats over the years, for me this would be a no-brainer.

Good luck, whatever your choice.


----------



## Caribbeachbum (Feb 23, 2014)

I would be wary if the design was for a fixed-keel yacht and the manufacturer offered a centerboard version as an option. But I think there are real advantages if the design was centerboard from the start. The Ted Hood-designed Bristols are a good example of this, or so I'm told.


----------



## Jeff_H (Feb 26, 2000)

To begin with, I would suggest that this is a very poor choice to build if your goals are lake sailing. Lake sailing tends to be a mix of extremely light air, and comparatively heavy air with relatively few medium days in between. This design would do poorly at either end of the wind range being obscenely heavy for a boat with this short a waterline length and being really short on sail area for lake sailing. 

Normally, for all of the reasons mentioned above, I would agree 100% that the centerboard boat should be a more practical design for trailering. I typically am a fan of well designed keel centerboard boats. 

But in this case, given your goals for the boat, I am not so sure that the centerboard version does make sense. Both versions of this design are severely short on sail area as compared to its drag, initial stability, and displacement. In the case of the centerboard version, there is less stability and so the sail area has been reduced as well. That would be okay if you normally sail in an area where the winds are rarely any more or less than 10 to 15 knots. But you are talking about both lake and ocean sailing and that requires a boat that is good at both ends of the wind range, which neither version would be, but the centerboard version with its smaller sail plan and stability would be much worse to the point of saying either change your sailing objectives or change your choice of design. 

I would respectfully disagree with the statement "I would be wary if the design was for a fixed-keel yacht and the manufacturer offered a centerboard version as an option." since has been routinely done on boats with longer keels, and produced successful equally successful designs. 

Jeff


----------



## Arcb (Aug 13, 2016)

For trailering, centre board for sure. And the mast would ideally be in a tabernacle. A boat you can not easily rig and launch solo, you won't use.

An alternative design I might consider for the kind of mixed usage coastal/inland trailering I might consider the B & B Core Sound 20 Mark 3. Water ballast cat ketch. Fast, light, easy to launch and can take some weather. I have been aboard these boats. They are pretty sweet.

Core Sound 20 Mark 3 | B&B Yacht Designs


----------



## outbound (Dec 3, 2012)

There are builders and there are sailors. If you are a sailor and want a very small boat which will be safe in the ocean would get a Flicka or something similar. By the time your done building and outfitting not much difference in cost. The difference between 2 1/2’ and 3 1/2’ is meaningless as to where you can go when sailing. Yes it’s a bit more of a headache when launching. But that additional foot is meaningful as regards righting arm.
So decide
Build or buy
Ocean or lake 
Daysail or cruise 
There are many great small centerboard day sailor designs. None are seaboats. There are a few very small ocean boats but the spectrum is large from minitransats to full keelers. The demands for an ocean v lake trailer boat are so different it’s hard to image a design satisfying such diverse requirements. If you’re ocean sailing you’d likely launch and leave in the water for days and cruise. If you’re lake sailing probably don’t even need bottom paint. If ocean you’d want something stout with a good avs. If lake something fast and fun. I think you will need to make up your mind. It’s sounds like you’d get more use out of a good centerboarder but don’t expect to cruise in open waters. I don’t get why people think coastal hops don’t require a substantial good boat. You can get into a lot of trouble within sight of land.
If you go lake would get a more modern design. Something with a better performance envelope. I’d get a folding tri but that’s my 2 cents. I say so as those are good bay and protected waters boats so quite safe for coastal cruising with a bit of common sense.


----------



## Chucknuckle (Oct 16, 2018)

I'm certainly not building the boat just to get on the water, I'd be mad to do that. The boat itself is the aim of the game, but when it's done I'd like to have some options with it. We have a substantial lake system (The Gippsland Lakes) on our doorstep, forecast winds for the rest of the week in the 10-20 knot range and I'd like to be able to use the boat there when finished, but we're also (relatively) local to places like Eden/Twofold Bay and I'm not opposed to the idea of driving up to the great barrier reef and pottering around the whitsunday islands, or putting in at one location and spending a couple of weeks sailing down to a pick-up point further down the coast in Queensland. So ideally I'd like a boat that can do both. 

Like anything boat-building or sailing related, everything is a compromise and in an ideal world I'd have a dedicated boat for both goals, but the Grey Seal is described by the designer as being slightly over-powered in terms of sailing in order to perform well in light winds, and all reports I've read from owners/builders describe her as handling extremely well in more powerful winds as well. Plus it's just a downright beautiful boat, I love her lines and her traditional look, I think it falls within my capabilities as a builder and is the right size for one or two people to spend an extended amount of time on. Maybe in the future I might look at a second hand folkboat or something similar for extended coastal cruising, but time and money only permit one project at the moment!


----------



## SeaStar58 (Feb 14, 2018)

Arcb said:


> For trailering, centre board for sure. And the mast would ideally be in a tabernacle. A boat you can not easily rig and launch solo, you won't use.
> 
> An alternative design I might consider for the kind of mixed usage coastal/inland trailering I might consider the B & B Core Sound 20 Mark 3. Water ballast cat ketch. Fast, light, easy to launch and can take some weather. I have been aboard these boats. They are pretty sweet.
> 
> Core Sound 20 Mark 3 | B&B Yacht Designs


I have been impressed with the B&B designs too especially considering how well they have performed in the Gulf of Mexico in some fairly grueling seas that have caused others to call for assistance.

The Belhaven design with its bilge keel/centerboard design which give a more open cockpit and cabin and is based a bit on the CoreSound is another one that appeals to me.
Belhaven 19 | B&B Yacht Designs


----------



## deniseO30 (Nov 27, 2006)

There is an ongoing discussion about Gray Seal building on Wooden Boat forum. 
https://r.tapatalk.com/shareLink?ur...share_tid=236486&share_fid=23945&share_type=t

Two very simple statements I would ask you to give lots of thought over.

"Sail, then build" vs "build to sail". Without knowing your actual sailing experience and abilities and just looking at the choice you're making, clearly you need two different boats.

I feel strongly about sailing then building because the boat you build will be strongly affected by the kind of sailing you do. and almost guaranteed, the boat you have or build will be too small too soon.

Also, it's pretty well-established that: it is not cheaper to build a boat than it is to buy one. Most often the Builder seriously and religiously builds a beautiful hull before they lose interest or run out of money because they didn't allow for the fitting out of the craft which is often another two thirds more in costs.

I often see new discussions on the Wooden Boat Forum about a boat someone just picked up from someone else that was building! 
so if you still want to build a boat I would suggest looking for a project that someone lost interest or ran out of money,. These are usually new builds.


----------



## fallard (Nov 30, 2009)

I had centerboard boats for 25 years and then got my swing keel boat 27 years ago. We are able to keep such boats in the shallow (2.5’ MLW) area in front of our house, which was a primary reason for buying them. 

However, we quickly found that variable draft allowed us to take shortcuts and to anchor in shallower water than a keel variant of the same boat. Being able to anchor in the fringes of a crowded harbor can be a real advantage. Extending navigation time in shallow tidal waters can also be an advantage. Being able to reduce draft is also an advantage in a soft grounding situation.

Bottom line: it would be real hard for us to switch to a keel boat when a swing keel/centerboard version is available.


----------



## outbound (Dec 3, 2012)

Fallard physics is undeniable. Each sailor needs to decide which boat is right depending upon how they intend to use the boat. For you and where and how you use a boat you made a great decision. But for someone else it maybe a poor one. For me the extra few degrees to windward, the slightly better avs, the decrease in complexity and maintenance, the slightly better ride are more important than draft. My problem isn’t getting into a nook or cranny but rather having enough chain.
The OP seems to like classic designs. He is building the boat himself. There is a significant increase in skills required to build a centerboarder and a significant increase in expense. Perhaps that’s worth it as there’s no question launching a boat with less draft off a ramp is much easier. Perhaps that’s the key thing in his decision and more important than gunkholing ability. The size he is contemplating is just large enough that centerboard maintenance isn’t him just rolling the boat on its side and working on the centerboard. He’ll need help and some ingenuity.i helped a friend do this. He dumped his boat off the trailer near a tree on his lawn. We rigged a block and tackle and lifted the boat to get to the centerboard. He replaced the pin , wire and pulley. This was done after the boat was placed in a cradle he constructed so it was elevated enough to work on. The board had a weighted shoe and was awkward. Was a two person job. 
I think he understands there’s a difference between a lake boat and an ocean one. If I truly wanted a coastal and lake boat as said would go with a Corsair or Dragonfly like design. If I wanted an easy lake boat with a classic appearance would go with a smaller centerboarder so less HAs with maintenance and give up on the idea of open waiter sailing. People think about sailing but often not enough about owning a boat.


----------



## Arcb (Aug 13, 2016)

I took a screenshot of the Gippsland Lakes on google maps. It looks nice, but challenging sailing on nearly any boat. A series of medium sized lakes connected by narrows, canals and wetlands. The OP is likely to be motoring a fair bit in nearly any boat except a specialised beach boat or cruising dinghy in this area. 

So if you like Grey Seal, go for it, but I would say get the centre board with all the shallows. Get a good engine for getting through the shallows, narrows and canals. If you really do want to trailer it, then see what options the designer has for solo mast raising systems.

*Or, you could just stick to the main bodies of water and you could probably sail just about any boat.


----------



## fallard (Nov 30, 2009)

outbound said:


> Fallard physics is undeniable. Each sailor needs to decide which boat is right depending upon how they intend to use the boat. For you and where and how you use a boat you made a great decision. But for someone else it maybe a poor one. For me the extra few degrees to windward, the slightly better avs, the decrease in complexity and maintenance, the slightly better ride are more important than draft. My problem isn't getting into a nook or cranny but rather having enough chain.
> The OP seems to like classic designs. He is building the boat himself. There is a significant increase in skills required to build a centerboarder and a significant increase in expense.


You can have the shallow draft and a decent ride with a properly designed swing keel boat-and go to weather with the best of them (keel down, of course.). The Clearwater 35 does all this, so that may be why I like what I have.

The OP has options if he is building a boat from scratch, but it may require the input of a qualified naval architect to achieve an optimum compromise. And yes, it will be more complex and costly to built variable draft. The Clearwater 35 swing keel boat cost about 30% more than the same hull with fixed keel and non-retractable rudder and your compromise is a keel trunk that splits the main cabin in half.

To reiterate my original point: We bought the boat primarily to keep it at our dock, but subsequently learned that the variable draft has been an immense advantage.


----------



## paulk (Jun 2, 2000)

Centerboards are useful for cruising in shallow water, but you do want something fairly sturdy for taking on ocean swells, even if it's just sailing coastwise. The design you suggest looks like it would be up for the task, but also looks like it would take a long time to build. Bruce Kirby has a design that might provide more performance in light air, looks good, and would be easier and quicker to build: Norwalk Island Sharpie Sail Boats by Bruce Kirby Marine | Sailboat and Yacht Designer of Laser, Sonar, Ideal 18, San Juan 24, Canada 1 and others It appears the design is robust and stable enough for heavier weather too: http://www.nisboats.com/pdfs/Charlie Fisher Bass Strait 1.pdf They're sold as kits or you can purchase plans:http://www.nisboats.com
I contemplated building a 29' one, but we ended up buying a used production boat because we wanted to spend more time sailing than building.


----------



## outbound (Dec 3, 2012)

Fallard don’t want to get into a pissing war. Especially as this is thread drift. Yes you have a wonderful boat. Yes, all boats have warts including mine which JeffH has pointed out. Yes, I think ( as does others) i have a damn good boat for a cruising couple crossing oceans but not perfect. If I had infinite sums I’d call BobP, or perhaps one of several European houses then NEB to watch a perfect boat for cruising being built. Yes, there are good centerboard boats for ocean work. Boreal or one of the Ed Joy boats come to mind. Still a 35’ weighted centerboard is at a disadvantage c/w bulbed, high aspect fin keel. Yes, it is the physics. Naval architecture has moved on as well. They are very skilled and smarter with this stuff than me or you. There’s a reason that even in the one off market where money isn’t limiting folks have moved on and similar designs as yours are no longer in production.


----------



## fallard (Nov 30, 2009)

outbound said:


> Fallard don't want to get into a pissing war. Especially as this is thread drift. Yes you have a wonderful boat. Yes, all boats have warts including mine which JeffH has pointed out. Yes, I think ( as does others) i have a damn good boat for a cruising couple crossing oceans but not perfect. If I had infinite sums I'd call BobP, or perhaps one of several European houses then NEB to watch a perfect boat for cruising being built. Yes, there are good centerboard boats for ocean work. Boreal or one of the Ed Joy boats come to mind. Still a 35' weighted centerboard is at a disadvantage c/w bulbed, high aspect fin keel. Yes, it is the physics. Naval architecture has moved on as well. They are very skilled and smarter with this stuff than me or you. There's a reason that even in the one off market where money isn't limiting folks have moved on and similar designs as yours are no longer in production.


For the record, Out, I wasn't in a pissing contest with you, just offering my opinion. OTOH, your comments come across as a bit presumptuous ("..smarter with this stuff than me or you", references to "the physics", and "..similar designs as yours are no longer in production."), considering you don't know my technical background and apparently are unaware that variable draft, ocean capable boats, similar in concept to the Clearwater 35, are still being manufactured by Southerly boats (https://www.southerly.com).

My point is that-getting back to the premise of this thread-you can achieve variable draft, stability, and competent sailing characteristics in the same boat, admittedly with other compromises and at significant additional cost over a keel boat. Perhaps the OP might have wanted to know that as he mulls over his options. I offered the example of my Clearwater 35 to establish an experience base for this position.


----------



## outbound (Dec 3, 2012)

I know and like Southerlies. A nicely made and thought through craft. Think it quite a different design however. Still think putting a whole lot of weight a distance down on a more effective foil simplifies the physics while allowing a better polar. Believe that’s why in spite of the complexity lifting keels have gotten more popular. We now can engineer and have the materials to do so so do so. I was not being presumptuous rather humble. Had an NA as crew it was amazing to learn how much is involved. I’m in awe by how complex this has become. I thought there were geniuses like the wizard of Bristol who just saw boats and ships whole in theirs mind eye and put down their vision. Yes there are still extraordinarily gifted people but they see it more like a complex vector diagram and it’s a team that creates these wonders. I’m sorry if I got your hackles up.


----------



## fallard (Nov 30, 2009)

outbound said:


> I know and like Southerlies. A nicely made and thought through craft. Think it quite a different design however. Still think putting a whole lot of weight a distance down on a more effective foil simplifies the physics while allowing a better polar. Believe that's why in spite of the complexity lifting keels have gotten more popular. We now can engineer and have the materials to do so so do so. I was not being presumptuous rather humble. Had an NA as crew it was amazing to learn how much is involved. I'm in awe by how complex this has become. I thought there were geniuses like the wizard of Bristol who just saw boats and ships whole in theirs mind eye and put down their vision. Yes there are still extraordinarily gifted people but they see it more like a complex vector diagram and it's a team that creates these wonders. I'm sorry if I got your hackles up.


Apology accepted.

Not to be argumentative, but my understanding is that the Southerly keels are aiifoil shaped cast iron and are pivoted from a cast iron "shoe". So the ballast system is a combination of keel and shoe. By comparison, the Clearwater 35 keel is also a NACA shaped foil, but has 2500# of lead encapsulated within the leading edge of the fiberglas keel. Another 2500# of lead is glassed into the very slack Clearwater bilge, creating a ballast configuration very similar to that of the Southerlies. The Southerly 35S keel is not what I would call a high aspect foil, but neither is my Clearwater keel, which has a similar-if not slightly lower-aspect. From a hydrodynamic perspective, the keels are similar, IMHO, and so too is the ballast weight distribution within the keel. However, the Clearwater shrouds are inboard, allowing the genoa to be sheeted closer to the centerline than on the heavier Southerly 35S, so I would expect the polars for the 2 boats to be comparable if not in favor of the Clearwater.

Both the Clearwater and Southerly designs incorporate a protective skeg to spare the prop in a grounding, but the Clearwater has a swing rudder vs twin rudders in the typical Southerly. The Southerlies were designed to handle grounding, with their cast iron shoe and the twin rudders to keep the boats upright.

If you check with Southerly owners, you would find the same enthusiasm for variable draft via weighted swing keel. Whether any of this scales to the size and boat construction of interest to the OP is arguable.


----------



## Chucknuckle (Oct 16, 2018)

Thanks for all the great responses! I have a vehicle suited to towing the Grey Seal and local cruising grounds within a 60 minute drive in several directions, so I would really like to be able to trailer her and not have something bigger which really needs to be craned into the water and permanently moored. What I'm balancing this against is perhaps a slightly less seaworthy boat if I get caught out and need to heave to in heavy weather, and (more pressing to my mind at the moment) is the added complexity during the build and for maintenance. And of course the added difficulty of launching a boat with a deeper draught.

I'm building the boat more to have the boat, than to go sailing, if that makes sense. I have no illusions that building will be cheaper than buying, and certainly not quicker! It's a project I expect to take two to three years, which I think falls within my capabilities but will also teach me new skills and challenge me. I'm also planning to use it as a way to spend some more time with my old man, as I have no doubt he will be spending as much time working on it as I will! My sailing experience isn't extensive, although I know the basics and have been out fairly often in my younger years. Time, money, and weather permitting I will be taking some classes and sailing on other peoples boats in the meantime while building the boat. I've picked this design not because it's the best boat (although all reports I've read from other owner/builders is that she handles very well) but because I think it looks beautiful and for the challenge of building it. I'm aware that the cabin is comparatively cramped and there are easier and faster boat designs available, but none of them give me a longing feeling like the Grey Seal does. The designer also has plans for a longer, 24'7" version of the same boat which would no doubt be roomier, faster and have better sea-keeping abilities, and I may look into that version, but I also feel like I'd be giving myself further problems when it comes to trailering and launching/recovering. One piece of knowledge I haven't actually looked into yet is how easy it will be to launch a boat of that size at the local marinas. Cranes are available so if worse comes to worst I would always be able to get the larger boat into the water, but I'd really like the process to be as painless as possible. Interestingly Iain doesn't offer a keeled version of the larger boat, only an offset centreboard, which would definitely be easier to construct than having to put the centreboard through the keel, and the draught is listed as no more than the smaller version of the boat. However, the longer boat means many more scarph joints for the planking and an increased materials cost. Food for thought.

Thankyou so much for the _Charlie Fisher_ read! That was excellent! What an amazing trip!


----------

