Thread: GIS Yawl

Very nice!

Clint,

You will have to be careful that Jia is not in one of the buoyancy tanks when you glue the top down.

MIK

Good tip, MIK.

You know that reminds me I swear I heard some faint meowing coming from Christophe's forward tank. It was especially noticeable on port tack and when we hit some chop it developed a sort of staccato sound.

Originally Posted by Compass Project

Good tip, MIK.

You know that reminds me I swear I heard some faint meowing coming from Christophe's forward tank. It was especially noticeable on port tack and when we hit some chop it developed a sort of staccato sound.

Did I ever tell you about my friends Henry and Al - both are really hotshot racing sailors - about as good as regular sailors get. Al used to build a plywood Moth dinghy each year to race and Henry decided to buy one of them and wanted a test sail.

Al is obsessive in a good way - his moths were around 35lbs hullweight (11ft boat) built of 0.7mm ply with 1.2mm in the cockpit. Al cared for them obsessively and NEVER got water inside the hull - that is the worst sin with Al.

The old style scow moths are very close to the water - about 8 inches freeboard.

Instead of screw in inspection ports they cut the holes but just cover them in stickyback contact plastic.

Al rigs the boat for Henry. Henry goes out on Sydney Harbour. And it is pretty breezy. Out of the inspection hole in the foredeck a kitten punches out through the plastic. Henry doesn't know whether to save the kitten or save the boat ... if he takes concentration off sailing he will nosedive and the boat will fill up.

Anyway some other people picked up the kitten.

When Al saw the plastic had come off and a bit of water got into the boat he was furious with Henry. Henry tried to explain about the kitten.

Al thought he was lying.

Such is life.

MIK

Mik, that is a great story.

I think the GIS was a catboat in a previous life!

You are wrong.

It was a kittenboat.

MIK

I'm working with my sailmaker, best in Maine called Hallett. They don't do a lot of lugs, but are familiar with allowances for spar bend.

My yard bends a little under 1 1/2" at the halyard attachment point, a little more aloft, with a weight equaling one third the sail area. So I know the sailmaker is clear, my pitch to him is that we want to cut the sail with enough round in the head such that when the yard is prebent with good halyard tension there is enough draft left in the sail to create some power. When the gust comes, the yard bends more (maybe 1/2" more?) and we want to flatten the sail aloft to depower and open the leech to spill wind. So allowing for 2" of flex in the yard would equal 2" of round in that portion of sail. Sail flattens out aloft in gusts but maintains some fullness for lighter air.

Mizzen will be cut with only a slight round to luff (3/4" of bend to mizzen) so that with halyard tension, the sail is flat.

I have a choice to make of sail material and think I'll be going with 4.5oz.

Clint

The bend will close to double in a big gust with a couple of heavy people working hard sitting on the gunwale.

At some point the bend will be limited by the sail cloth. It is hard for the bend to exceed the round cut into the sail as the sail will restrain the spar from bending further.

MIK

Originally Posted by Boatmik

At some point the bend will be limited by the sail cloth. It is hard for the bend to exceed the round cut into the sail as the sail will restrain the spar from bending further.

MIK

This must have been the reason my floppy thing didn't break that day at Port Stephens. Still, I was conscious of it and nursed it a bit on the "bad tack" where it bends against the mast.

one has to be careful of one's floppy thing.

I think on the evidence you might be sitting in the wrong place by that description.

Originally Posted by Boatmik

one has to be careful of one's floppy thing.

I think on the evidence you might be sitting in the wrong place by that description.

Haha, very funny.

Looking forward to my carbon tow arriving so I can begin experimenting a bit.

Originally Posted by Boatmik

one has to be careful of one's floppy thing.

Can I quote you on that!?

Looks like a booboo I can't live down or up to

I just put my order in for the sails. We have a few questions to work out. On the basis of peoples' feedback, I added a set of reefpoints between the boom and first row. I like this idea. I call it the 'child's reef'. Anytime there is a child aboard, that reef goes in. In my meeting with the sailmaker, we were looking at the top row of reefpoints, waaayyyyyy up there. Now, I did notice that Al used them, but has anybody else? I was thinking of bringing that row down so that they are all equally space.

By the way, the GIS Yawl plan is available now for free. Thanks to MIk, of course, but also to John Goodman for having the determination to work through the problem solving to get his yawl figured out and successfully launched. Enjoy.