On Sun, Jul 11, 2004 at 09:37:58AM +1000, Rick Measham wrote:
> The main reason I wanted a polygon area over a
triangle-or-quadrilateral area is because I've seen Chinese Junks
that have sails with several gafs, for which you need an n-sided
> polygon.
At 12:31 am -0400 2004-07-11, Ben Okopnik replied:
Arrgh. As a sailor of some twenty years, a live-aboard and long-distance
cruiser for the last dozen-plus, and a big-time fan of junk rigs, I've
just _got_ to stick my oar in. :) You can't have multiple gaffs; those
are full battens and a single gaff. As to a concern expressed by
someone else earlier with regard to sail camber, don't worry about it:
unlike a Bermud(i)an rig, junk rigs aren't cut to have any curvature in
the sail material itself; they get their shape from the positioning of
the battens. Interestingly enough, many modern Bermudian rigs that are
designed for ease of use are now made with full battens as well, thus
coming full-circle...
Hey, I wouldn't have a clue what they're called! I just took a guess
that they'd be called gaffs because of one of the pictures I saw in
the original question.
Now, if all the sails in the original problem have, as you suggest,
some curvature, then surely the junk rig is the only one for which
the solutions really work. The others need to allow for some
curvature? The junk rig, being flat, is a flat polygon and can be
calculated as a polygon?
Cheers!
Rick Measham
(Certified Land Lubber)
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