On Sun, 3 Jul 2011 13:03:25 -0400, "Wilbur Hubbard"
wrote:

"Wilbur Hubbard" wrote in message
anews.com...
"CaveLamb" wrote in message
m...

snipped Bruce's speculation


That foot looking loose has me puzzled.
Because it does. But when I tensioned it it looked worse!

We had no tension on outhaul or vang in that run.
It looks like the foot of the sail is trying to slide aft a bit.
There is no slug at the clew, and the tack fitting doesn't pull it
forward in line with the rest of the luff. It's only an inch or so.
But it might need to be retained there better. Just add a slug at
the bottom?

And I'm going to have to come up with a gate setup at the slot where
the slugs go into the mast. There is a sail stop there now, but it holds
the stack up about 5 inches. I don't know if there are more slugs on
this
sail or what, but it sure stacks a lot taller when furled!


Don't add a slug at the bottom of the luff unless you know for sure that
the tack hook is in line vertically with the mast track slugs. The tack of
the mainsail may be placed so it is NOT in a vertical line with the mast
slugs. This may be due to the fact that the tack hardware sits a few
inches aft on the boom. Mine is built that way so the sail was especially
cut and the tack cringle is four inches aft of the vertical line formed by
the mast slugs.

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\o________o\



But, there SHOULD be a sliding slug at or near the clew. It should slide
easily and it should be lubed with silicone spray so it keeps sliding
easily. The outhaul should be used to keep it from sliding forward and to
flatten the sail as required. The track in the boom also needs to be kept
slippery. If you have slugs or even if you have a bolt-rope in lieu of
boom slugs. My mainsail has one sliding slug at the clew and a boltrope
the from clew to tack. This is a true shelf-foot. When the sail is bellied
out all the way the shelf assumes the perfect shape with no wrinkles. When
the outhaul is pulled tight the shelf assumes several folds that make it
appear to be no shelf at all. All told there is about six inches
difference of foot length between flat sail and full sail.


Oh, one more thing. The bolt rope, if any, on the foot of the mainsail MUST
be nylon so it can stretch adequately. Dacron halyard line is not suitable
because it doesn't stretch enough.


Willie, Wrong again.

Assuming that the sail is attached to the boom and not loose footed,
to properly rope the foot the sail is stretched, often using a tackle,
and then the rope is sewn to the foot. The purpose of all this is to
reinforce the foot of the sail and to limit the amount that the sail
can be stretched by the out haul.

As the purpose of the foot rope is to limit the stretch of the foot of
the sail, using a nylon rope would defeat the basic reason for the
roping as nylon rope has up to 40% stretch and it would be impossible
to sew the rope to the sail to do this - it would mean that the foot
would be 40% shorter with tension released.

Try http://www.schattauersails.com/ultimateoffshore.html
and http://www.sailmakerssupply.com/prod_detail_list/26
for additional information.

Cheers,

Bruce