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Old 05-24-2013
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Re: Bob Perry's take on Wolfenzee's dream boat

Wolf:

I would agree with you that most of what has been discussed falls heavily into the category of 'wants' not 'needs'. You and I would probably agree that the only true 'needs' are food, water, air, and shelter from extreme conditions. Anything else is a 'want'.

Many of these suggestions would be improvements to the way your boat would sail. So some of of the participants in this thread would want these things if this were our boat, and so consequently have suggested these items thinking that you may wish to think about adding them at some point.

My comments on your mainsail result from me interpreting your post #317 as you saying that you want a new mainsail and are saving to buy one. My comments are only aimed at making sure that you understand what you are buying, and because your comments show that you have no clue about the realities of what you are saying.

First of all, actually measuring Atkin's drawings, it appears that Atkins has drawn the boom almost 20 feet long. That means that your boom is approximately five feet shorter than the original design. If your boat balances so well now, that means that Atkins really blew it badly. That would move the center of effort of the mainsail roughly 3'-4" forward of its original designed position. That is enormous. We normally think of a changing rake and inch or two as a big correction. Then when you add the increased jib luffs, that moves the center of effort even further forward.

As to the mainsail you seemed to mention wanting, while you did not mention the words 'hollow leech", the reality is that any reputable sail maker would not try to build a battenless mainsail without a hollow leech. A straight battenless leech would beat itself to death very quickly and would need a large leech cup to minimize that. The typical accepted recommendation for leech hollow on a battenless main falls between 2% and 5% of the leech length depending on the intended use of the sail, and its construction. 2% is 10" and 5% is roughly 2 feet.

If you sail maker has not explained that to you, then you really need a new sailmaker because no competent sailmaker would recommend a batten-less mainsail without explaining the buyer the generally accepted realities, i.e. that they have a shorter lifespan than a fully battened mainsail, that they have a hollow leech, and that therefore they have way less area.

Measuring the actual drawings, with a 15 foot boom, you could easily have as much as 18" to 20" of roach on your sail. That means that minimally, you are losing close to 50 feet of sail area. That is huge.

Respectfully,
Jeff
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Last edited by Jeff_H; 05-24-2013 at 02:43 PM.
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