Dave Cannell ) writes:

Google for "tyvek sail" (w/o the quotes), several interesting ones in

leave the quotes around "tyvek sail" when doing a Google search or you'll
get everything that has tyvek or sail in it, 'way too much. you just want
references to websites that ahve both tyvek and sail. Another way to get
them both is to put a plus sign between tyvek and sail, ie tyvek + sail.

I've made cheap sprit sails out of nylon and cotton canvas. there are
photos and descriptions on my website (see below) plus a file of
information on making sprit sails. There's a diagram for cutting a sprit
sail in the design for the 15 ft solo cruiser.

ordinary nylon cloth comes in 5 ft wide rolls. you have to use the kind
you can't breathe through. if air can pass through the cloth the sail loses
a lot of power. the nylon will stretch a lot on the bias. because of the
stretch it won't sail upwind very well. all that is mentioned in tF Jones
"Boats to Go" where he discusses a cheap nylon sail for canoes and kayaks. I
got around the bias stretch by using two thicknesses of nylon at 45 deg to
each other. My boat sails upwind fine.

cotton canvas is good. it will let some air through so look for a tight
weave. before they had synthetic sailcloth they used to throw buckets of
water on cotton canvas sails during races to get the threads to swell up
and keep air from passing through the cloth. My sail works fine. Notice
that it has a mast sleeve and a loop for attaching the sprit sewed into
the luff of the sail.

Bamboo makes nice light spars for very small boats. I have a bamboo mast
and sprit for the cotton canvas sail. The nylon sail used to have a bamboo
mast and sprit until they got wet, softened, and broke. The nylon sail has
a fir mast cut from a 2x4. A 2x4 is actually 1.75 x 1.75 so if you slice
off 1.75 you get a square piece. you can then set a circular saw to 45 deg
and rip off teh corners to ge a 8-sided piece. I forget if I drew lines on
the stick to guid teh cut or if I had bought the rip fence of the saw by
then. the rip fence helps but they cost $10 or so. I rounded the stick
with an old hunting knife and smooted it by scraping with a thick piece of
broken glass (bottom of a broken bottle). No need to buy a plane. My last
innovation was to make a sprit from 3 metal broom handles that comes apart
for transportation and stowage. That has worked well.


--
------------------------------------------------------------------------------
William R Watt National Capital FreeNet Ottawa's free community network
homepage: www.ncf.ca/~ag384/top.htm
warning: non-freenet email must have "notspam" in subject or it's returned