Wharram Builders and Friends

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Hello, I  read  the optimist pram test and the Marchaj wind tunnel article thats why I gave the crab claw another chance.  Windward ability is not the only thing we look for in a rig. We don't all need to point like a race boat . We do however need to point like a cruising boat, especialy when reefed. Getting away from a lee shore in a blow is a very important ability for any cruiser. I believe a  boat should be able to point 45 derees to aparent wind, minimum. I encourage folks to do their own tests on crab claw and other rigs. I noticed Wharram is revisting the sprit sail in his latest design. I did not mension in my earlier article that the lugsail developed more power than the crab claw. I often sailed 1-1 1/2 knots faster with the lug. If the crab claw undergoes  further testing and development I am shure it could point better but not great. Hell, maybe ill give it another try! It shure is pretty.....Kevin

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Comment by Scott Veirs on February 17, 2015 at 4:16am

Here's some data --

http://econscience.org/tiki/2015/02/15/performance-of-a-bamboo-poly...

Share yours if/when you gather it.  We've got more coming from a Hitia 17 that really needs to go upwind in light air this June in the Race to Alaska...

Comment by Kevin Hutchinson on February 21, 2015 at 6:58am

 Hello Scott, I am so glad you did an evaluation of the crab claw. I would love it if someone take something like a laser day sailor and tried different rigs  of equal size  upon it  .  That would give a nice apples to apples comparison.  I did it on my sailing kayak not the most efficient sailor by any means. I think I was tacking about the same you were about 135 degrees between tacks . For me I need better windward ability than that. I think it is a safety factor to be able to sail away from a leeward shore it is vital in a cruising boat.   The lug sail pointed better and had more power than the crab claw. I think a way to get the crab claw to windward is to make it loose footed  this will make it more like an upside down windsurfer sail. Oh course this will kill the vortex effect. To tell you the truth I never felt this effect except maybe when running before  the wind. By the way everyone keeps saying the crab claw is a cheap rig to make . If I made a conventional rig from bamboo ,ropes ant polytarps it would be cheap as well!

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