Centerboard Keels in Blue Water Vessels

[barnakiel]

I do not have a centerboard but to me it makes a lot of cruising sense. Exactly - cruising - because for a crossing maybe nothing beats a 10' draft with a lead bulb;-), BUT once inshore and exploring I wish we had the centerboard.

So my strong YES to centerboards in the cruising aspect.

b.

[Bash]

yes, barnakiel. We could define "cruiser" as: "someone who spends half the time underway wishing there were more draft, and the other half wishing there were less."

the problem: how do you make centerboards work (economically as well as mechanically) when the ballast exceeds four tons of lead?

[Sharkman]

Originally Posted by Bash

yes, barnakiel. We could define "cruiser" as: "someone who spends half the time underway wishing there were more draft, and the other half wishing there were less."

the problem: how do you make centerboards work (economically as well as mechanically) when the ballast exceeds four tons of lead?

Hi Bash

in OVNI's the board is not ballasted, just flat plate. On ours the plate only weighs around 120kg of a total ballast of 3600kg. The balance is lead encapsulated in the bilges. So when the plate is lifted off the wind the centre of gravity is hardly affected. Having internal ballast makes for a smooth ride, too.

Mechanically this means that the hydraulic system is not having to work too hard, and so only uses glycol as hydraulic fluid. When approaching shallow water the hydraulic controls for plate and rudder are put in the "up" position, so if the boat touches all that happens is that the plate or rudder lifts with no resistance. When under way with the plate and rudder down they are locked in place by hydraulic pressure. In the event of a collision there are copper core plugs in the top of the pump that rupture, thus reducing the risk of major damage. The pump is just inside the top of the starboard cockpit locker, and easily accessible. jimmy Cornell reported hitting a log in heavy weather in his OVNI 43 and this fail safe system worked perfectly.

Hope this helps explain one approach to your query.

[danielgoldberg]

Someone mentioned the Southerly's already, but note also that the Shards are cruising pretty far afield in theirs. They also did a video where they beached the boat in the Bahamas. Looked very cool.

[Sailndive345]

Originally Posted by Sharkman

.... When approaching shallow water the hydraulic controls for plate and rudder are put in the "up" position, so if the boat touches all that happens is that the plate or rudder lifts with no resistance. ....

Sharkman,

I have been a fan of Ovnis and Garcias for quite some time - wonderful boats, hope you have been enjoying yours.

I am curious about what you described above - This is assuming that you would make contact with the bottom or something hard (!) only while making way 'forward'? Do you ever worry about impact while making leeway? Do you think the board would withstand the forces and not get jammed in place?

Fair winds!

Sailndive

[James S]

I've never sailed any thing with a center board bigger than an O'day day sailor....and never really fancied having one...that is until my recent trip to a boat show.
Most of the boats were indoors and to get into them you climbed up these great big tall scaffolding sort of platforms...so here’s all these sailboats towering above everything with these great long keels.....and then there's this 40 something with a centerboard sitting right down on the floor....like 3ft to the water line.
It was a big visual thing for me, and actually did get me thinking.

[conachair]

There are a lot of Ovnis out there so they must work. One thing I´m jealous of is how easy it is and how little tide you need to dry out for a scrub on a beach. Major advantage for bluewater cruising where you might go for a very long time away from any other way of drying out.

[James S]

The one I saw at the show was an Ovnis.

[Sharkman]

Originally Posted by Sailndive345

Sharkman,

I have been a fan of Ovnis and Garcias for quite some time - wonderful boats, hope you have been enjoying yours.

I am curious about what you described above - This is assuming that you would make contact with the bottom or something hard (!) only while making way 'forward'? Do you ever worry about impact while making leeway? Do you think the board would withstand the forces and not get jammed in place?

Fair winds!

Sailndive

Hi Sailndive

There's no doubt that the plate could be damaged (likely bent) by a serious side impact, but given the way the pivot works, and the massive nature of the pin etc., I'd be almost certain that as long as there was some upward thrust the core plug would rupture. I know that if we touch in any plane we are likely to have the plate control in the 'up' position, in any case. It's standard practice for us to do this in shallow water or a narrow channel, just like the old Thames barges with their leeboards - 'touch and go'.

I have heard of a couple of boats that have bent plates - one at least when the plate was caught in a rock cleft during a grounding. But you'd have to ask what damage might have occurred to a 'conventional' boat in similar circumstances?

In the latest edition of 'Voiles et Voiliers' (excellent French sailing mag) there is an account of a guy who has sailed his Garcia Maracuja single handed around the world south of all three great capes, amongst other exploits. During that time he has been stranded for five days on an atoll in the Tuamotus before the French Navy towed him off, and survived a further stranding in the Chilean canals. On his way to Cape Horn his plate sheared off, but he made it to port OK and fitted a new plate with the aid of friends. There is no mention of whether the damage that caused the plate to shear off was caused during the two groundings, but you'd have to wonder. And either grounding might have finished off a lesser boat, in any case. And he's still out there after 120,000 miles in the same boat.

So plates can be damaged, but that's certainly the only one I've ever heard of breaking. But we're talking pretty extreme stuff here, and given the numbers of this type of boat sailing in far flung places, the track record is still pretty good we feel.

And we like ours very much, thanks - they are different, and take a little bit of getting used to, but the positives far outweigh the negatives. The sheer strength of the boat is very reasssuring, and she sails really well. And more and more we use the shoal draft for exploring and dropping anchor where others can't go - going back to 7ft draft would be very hard now.

Best wishes

[estarzinger]

I think a good cruising boat should either be able to sneak into shallow water or to be able to sail well upwind. Both of those things are fun, challenging and let you get away from the crowds.

Our first boat was a centerboarder, and our current one is a witch upwind.

It would of course be ideal to have a boat that could do both, but that is a tough, almost impossible, design challenge and I am not aware of any cruising mono that can do both well. A tri is a design solution to that challenge but they have their own drawbacks.

I prefer to minimize the number of moving parts under the water. If I did a centerboarder again I would hope for the top of the trunk to be above waterline so it could be worked on without hauling the boat.

[Sharkman]

Hi Evans

Totally agree with your analysis, the only thing I'd add is that in our view the added 'nuisance' factor of the board only makes sense if you end up with real shoal draft and beachability. If all we'd gained was a couple of feet less draft, we wouldn't have bothered for the very reasons you outline - there's no doubt that there is more to potentially give trouble with a board, and there's more maintenance.

As far as upwind performance goes, they are not the fastest or highest pointing boats, but we knew that before we got one. Ours is weakest in light airs upwind with our yankee/staysail combination, but we're hoping to do something about that with a new light weather genoa that we're having made. Upwind over 10 knots the boat is fine as long as you don't try and pinch - like this she'll make 6-7 knots at around 45 degrees to the wind, and the motion is comfortable enough. After 17 years with a German Frers IOR design upwind was always going to be a disappointment, but I'd have to say that the OVNI is no worse than many fully loaded cruising designs we come up against, and off the wind she's great.

And the inspection plates in the box area all above the waterline, so that the hydraulic ram can be inspected (all but one plate is perspex) and the ertalyte guides for the board can be inspected and cleaned. It's simple and it works OK.

The compromise works well for us - as you say the ability to get into quiet spots is sweet, and we're really beginning to use the shoal draft as our first choice in deciding where to anchor. And I still hope we'll get a bit more out of her upwind!

Best wishes

[barnakiel]

Originally Posted by Bash

the problem: how do you make centerboards work (economically as well as mechanically) when the ballast exceeds four tons of lead?

As per other posts, do not put all your ballast in the centerboard/daggerboard OR have it operated with mechanical purchase/hydraulics, etc..

b.

[estarzinger]

Originally Posted by Sharkman

the only thing I'd add is that in our view the added 'nuisance' factor of the board only makes sense if you end up with real shoal draft and beachability. If all we'd gained was a couple of feet less draft, we wouldn't have bothered for the very reasons you outline - there's no doubt that there is more to potentially give trouble with a board, and there's more maintenance.

Completely agree. I think some of the worst design compromises are centerboard boats that are not very shallow with the board up.

I would not work too hard on upwind . . . We have discovered there is a real big disadvantage to having a boat that goes upwind really well . . . since you can do it, you end up actually doing it . It is great fun in a flat water day sail, but . . . while the boat really enjoys upwind offshore in waves for several days, for the crew it is really not so pleasant. With the center boarder we usually just changed our plans and went somewhere else on a reach or hove-to until the wind changed.

Its a psychological problem ( I think the clinical term is "stubborn as a mule"), since we know we can do it, we tend to keep going upwind when it would be easier and more pleasant to give up on that destination and just pick another.

[CarlF]

Some centerboard boats can be tender and lack upwind sail carrying capacity - but remember that the Hinckley B40 has a centerboard and has crossed many oceans, circumnavigated, and won the Bermuda race which is an upwind offshore race in rough waters.

Another advantage not already mentioned for the blue water centerboard boat is that it is far less likely to become ensnared on fishing gear or other floating mid ocean hazards. This can be a life threatening problem if someone has to go in the water to clear it.

Centerboard boats also typically use encapsulated ballast and therefor lack the single worst piece of engineering in modern sailboats - keel bolts. The loss of a keel can and does kill people, yet to save a few dollars most builders persist in using the wrong metal (stainless instead of bronze) to secure an extremely heavy object to too small a keel stub. Conventional practice uses no keying or other fiberglass reinforcement for the keel. Worse, there is rarely a telltale sign of a broken or corroded bolt. The only reliable way to check the keel bots is to drop the keel - if it's possible to dissemble the interior to reach all of the bolts. This expensive adventure always requires a boatyard - and a good one at that. If your boat has ever had a hard grounding or is more than ten years old -- and you've never dropped the keel - those bolts should worry you.

On the other hand, a centerboard will not put the boat or crew at risk if it sticks up, sticks down, bends, breaks or falls off. In fact, the boat can quite safely finish whatever voyage it's on. While wooden centerboard boats could open a seam around the centerboard trunk, this isn't a major risk with a well built fiberglass or aluminum boat which are easy to overbuild around the centerboard trunk. I once removed and replaced a centerboard with a friend using a mask with the boat moored off a beach. Try that with a keel.

Carl

[Sailndive345]

Originally Posted by Sharkman

Hi Sailndive

There's no doubt that the plate could be damaged (likely bent) by a serious side impact, but given the way the pivot works, and the massive nature of the pin etc., I'd be almost certain that as long as there was some upward thrust the core plug would rupture. I know that if we touch in any plane we are likely to have the plate control in the 'up' position, in any case. It's standard practice for us to do this in shallow water or a narrow channel, just like the old Thames barges with their leeboards - 'touch and go'.

I have heard of a couple of boats that have bent plates - one at least when the plate was caught in a rock cleft during a grounding. But you'd have to ask what damage might have occurred to a 'conventional' boat in similar circumstances?

In the latest edition of 'Voiles et Voiliers' (excellent French sailing mag) there is an account of a guy who has sailed his Garcia Maracuja single handed around the world south of all three great capes, amongst other exploits. During that time he has been stranded for five days on an atoll in the Tuamotus before the French Navy towed him off, and survived a further stranding in the Chilean canals. On his way to Cape Horn his plate sheared off, but he made it to port OK and fitted a new plate with the aid of friends. There is no mention of whether the damage that caused the plate to shear off was caused during the two groundings, but you'd have to wonder. And either grounding might have finished off a lesser boat, in any case. And he's still out there after 120,000 miles in the same boat.

So plates can be damaged, but that's certainly the only one I've ever heard of breaking. But we're talking pretty extreme stuff here, and given the numbers of this type of boat sailing in far flung places, the track record is still pretty good we feel.

And we like ours very much, thanks - they are different, and take a little bit of getting used to, but the positives far outweigh the negatives. The sheer strength of the boat is very reasssuring, and she sails really well. And more and more we use the shoal draft for exploring and dropping anchor where others can't go - going back to 7ft draft would be very hard now.

Best wishes

Those sure are great testimonials in favor of these boats!

One of my favorite features that the Garcia offers is the stern daggerboard (just in front of the rudder) - so much so that I envisioned adapting something like that to my fiberglass boat Have you seen any such additions to Ovnis? From all I have heard, the daggerboard helps the Garcia track almost as if she has a long/full keel.

Fair winds!

Sailndive