Outhauling and Mast Bending

JBlumhorst@aol.com
Sat, 22 May 1999 13:19:49 EDT


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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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Hi Webgang,

The issue of how the too-short boom makes the sail too baggy is really the
same as how bending the mast makes the sail so much flatter.

If you restore the extra 1.5 inches of outhaul to the boom by extending it,
you take 4-5 inches of draft out of the foot of the sail.

If you bend the P19 mast forward one 1.5" at the level of the draft, you take
4-5 inches of draft out of the sail at its most powerful section.

An inch or two of outhaul or forward mast flex can reduce the draft in your
sail by 50% (very rough approximation)

It's not intuitively obvious, but that's how it works. In fact, it's so
counter-intuitivethat I keep checking my reasoning to see if I'm missing
something. But compressing that 10' peice of PVC pipe by 1.5 inches and
producing 5" of "draft" was very convincing.

Regards,
Judy