Practical notes of this kind, are worth waiting for.

Thanks

Brian W

On 27 Jun 2004 14:01:47 GMT, (William R.
Watt) wrote:

//
This tells how I made a 30 square foot sprit sail out of tyvek
(tm Dow Chemical) house wrap.
//
Before making the sail I cut an 8.5 ft, 1.75x1.75 inch mast
out of a used 12 foot spruce 2x4. The corners were roughly sawn
off with the blade set at 45 degrees to make an 8-sided mast and
then a 40 pound weight was suspended at the midpoint of the luff
to measure the mast bend. (The weight is supposed to be 50 pounds
but I had a 40 lb concrete block handy.) That's when the mast
broke. My plan to cut around some nail holes in the wood had not
worked out. I went to the public library, consulted Fred
Bingham's book, made an 8-sided spar gauge according to his
illustration, and cut a shorter mast out of an 8 foot spruce 2x4
which had no nail holes in it, avoiding the larger knots. The
mast has a 2 inch bend, the same as the 7.5 ft mast for the
existing sail which was also cut from a spruce 2x4.
//
All of the descriptions of tyvek sails I found on the Internet
used double-sided outdoor carpet tape to join the seams.
//
Cutting the tyvek was easy. The scissors did not have to be
opened and closed, just pushed along the pencil line, cutting
like a knife. Sewing the tyvek was a lot easier than sewing
cloth.
///
Tyvek is very stiff. It makes a loud noise
when it moves
///
6. Someone wrote on the Internet that grommets do not hold up
well in tyvek. One eighth braided nylon line was hand stitched
along the edges of the corner reinforcements leaving a loop at
the corners for tying on the sprit and mainsheet. The line was
crossed over itself at the corner so the strain is directed along
the line.

- END -