The lashings are tight. One piece from top of sail to bottom, wrapped around the mast in a spiral, with holes every metre or so. Then through a block at the bottom, up to the tack of the sail (which is also the last hole the spiral wrap goes through, back to the pulley, then pulled as tight as I can get it. So far it tacks well (I have not watched it as too busy shunting, but it is to leeward when I start the shunt, and to leeward on the other side when i complete it. I will try and get some photos next sail.
No idea if it will have too much friction with 3 sections of mast up, but it would not be a big deal to run a second lashing for the top half if it was. So far, this is definitely a success.
On Sun, Apr 16, 2017 at 5:41 PM, lucjdekeyser@telenet.be [harryproa] <harryproa@yahoogroups.com.au> wrote:
Thank you Mike. Sadly attachments do not show up in messages with me. But I have seen plenty of pictures of hooped sails on Dutch traditional boats. The gap with the mast is most often not negligible. I assume that the loose lashings are shaped like a luff pocket sail. Rod's lashings showed to be very tight to the mast on the one picture. I was wondering if this setup would mimic a mast with a track to lee. If not and the lashings allow the sail to rotate freely I would expect the luff angle to be the bisector of the angle of an equivalent luff pocket which would be less to lee than optimal.
This would suggest theoretically the design of a non-rotating mast with a fore-aft symmetric biconcave foil with blunt edges and more concave to lee (to mimic a wing mast rotated for up wind) and with a track in the middle of the lee surface to fix the lee side of the imaginary luff pocket. Of course with all the complications of a bare pole wing mast.
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Posted by: Rob Denney <harryproa@gmail.com>
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