Centerboard Boats: swing keel = no blue water?

[Christopher]

In my boat shopping spree extravaganza in the last month or so I've come across a number of centerboard boats.  A lot of Tartans seem to have them and some others.  Anyone have any opinions as to the durability, reliability, and ease of maintenance on boats equipped with a centerboard?  They are somewhat attractive for me because I like the idea of being able to get in shallows, but also wouldn't mind a deeper draft on the occasions that I race.

[Christopher]

I'll be more specific and refer to the S&S Tartan 27.  This is a centerboard boat, but as I understand has a 3' + draft without the centerboard.  I believe there is a good amount of ballast in the shoal as well..

I think this is much different than the swing keel variety boats...

Not sure though... I'm concerned about the maintenance on something like this.. and also how much more tender is it than something with a fixed full keel.

[LooseMoose]

Centerboards (and dagger boards for that matter) make all kinds of sense... Our last boat only drew 18 inches (board up) and we sailed some 25,000 miles on it and never had a problem.

As to the old canard of shallow draft not being seaworthy or blue water capable ...well like I said it is a canard.

Bob

http://boatbits.blogspot.com/
http://fishingundersail.blogspot.com/
http://islandgourmand.blogspot.com/

[Oldrig]

The Tartan 27, with a drop keel (I guess that's because the centerboard is in the bottom of a small keel) has a great reputation. I've sailed on a friend's boat and enjoyed it a lot.

Some articles on the T27 warn that you should check the pivot mechanism for the drop keel very carefully before buying, however. If I remember correctly (doubtful at my age), it can be very difficult to repair/replace when it goes.

Good luck.

--Joe

PS With all my recent groundings, I'm well aware of the advantages of centerboarders.

[ThistleCap]

Dear Chris,
I think maybe centerboards and swing keels are being used interchangeably.  There are huge differences.  As to your question, 'swing keel=no blue water', I'd agree.  A centerboard really adds nothing to righting moment.  It's purpose is to improve lateral resistance (decrease leeway).  My boat came with a mild steel board, which I replaced with stainless on a 1" stainless pin.  It's only 80 lbs., so wear and stress on the pin is negligible.  The advantage of the keel/centerboard boat, a design used in several famous ocean racing boats, is the boat has the ballast it needs in the short keel, and can be sailed effectively with the board up.  The board is used only when on the wind.  The swing keel is an entirely different animal.  It means the boat itself has little or no righting moment of its own.  The weighted keel in the up position adds some righting moment, but in the lowered position increases righting moment because of the increased lever arm, while also increasing lateral resistance.  The stress and resulting wear and tear on pins and pennants with a swing keel are much greater because of the 800-1000 lbs. or more of weight in the swing keel.  Designed for inland waters, the swing keel boat has little chance of capsizing, because it usually takes the dynamic forces of a breaking sea to capsize, which are mostly absent inland.  The reason I wouldn't take a swing keel to sea is because the chance of a capsize does exist there.  An 80 lb. centerboard dropping back into the boat will be unlikely to cause structural damage.  A half-ton of lead or cast iron dropping back into the boat is a whole different thing.   Even in normal use, a pennant failure dropping the swing keel can cause serious problems.  A friend had this happen, and the dropping keel split the hull forward of the trunk.  He was still at the marina, and barely avoided sinking by getting into the travel lift right away.

Bruce Caldwell did a nice piece for SailNet.  I'd disagree with him on one point.  He says if the pennant breaks, it's game over and back to the yard.  The only thing that will happen if the pennant breaks is you can't raise the board.  If you're on vacation, you just keep on.  The only impact on your trip is you need to anchor in deeper water, and you can't back up in shallow water.  You can go forward in shallow water, but not reverse.  You could even ignore the board until the next winter haul out.  If it's a simple failure, the repair can be done with a set of dive gear.  It's another matter if the pin breaks, a much more serious problem even with the centerboard, but with a swing keel may mean loss of the keel if the pennant can't bear the load.  Knocking the pin out every half-dozen years for inspection is all that's needed to avoid such a problem.      

[Oldrig]

Oops, I should have said "swing keel," rather than "drop keel."
That's a totally different thing.
Sorry.