Thom,

I'm not sure you understand MY shelf-footed main. It has no elastic material
comprising the shelf. It has the same 6.9oz Dacron as the rest of the sail. It
is the shape of the panel that constitutes the shelf foot that gives it it's shape.

The bolt rope definitely gives the foot of the sail support as it slides into the
internal track in the boom. Note in the photo how the sliding slug and the bolt
rope line up. Both keep the foot onto the boom and have the added virtue of
spreading out the forces over a greater area than with a clew only like your
set-up.

My friend you have a weak understanding of my clew and sails in
general. Anybody who can even abide a roll-up headsail proves he
has low standards and is willing to compromise performance for
convenience, which convenience leads to all sorts of additional
problems usually at the very worst times.

And, of course, all those layers at the clew patch are sewn together.
Done properly, which they are, those webbing straps are as unnecessary
as tits on a boar hog.

CN

"Thom Stewart" wrote in message ...
Neal,

I'm not sure you truly understand your main sail. That bolt rope on the
foot of a shelved main give NO SUPPORT! A shelved main is a free footed
main and anchored only at the TACK and the CLEW. That shelve is an
elastic material which is designed to let the full airflow shape of the
sail continue to the bottom of the sail. It is the assure that the air
doesn't form a vortex at the Boom. The material is meant to be loose
enough to let sail shape carry to the foot of the sail.

All those layers of of cloth mean didderly without the stitching to
prevent the shearing action that take place at the Clew corner. The slug
is a nice feature but a Clew Strap is something you should install. With
a free footed sail an awful lot of strain is put on the Boom slut.

Neal, my friend, you have a weak Clew on that sail.

Ole Thom
P/S Neal, stop kidding yourself that the shelve is working as a system
for STRENGTH. It isn't!!


http://community.webtv.net/tassail/ThomsHomePage

Well Neal,

You're proven you inability to accept the truth about the action of a
"Wing Keel", the fact of a low profile PH, the advantage of a furler on
a cruising boat, and now the actual operation of your own Main Sail. The
scope of your known ignorance continues to grow. Explanation seems
hopeless.

I will try, once again, to enlighten you. Your SHELVE, it has excess
material so that as the foot of the sail forms its curve there is no
resistance applied by the shelve. As you flatten your sail, the shelve
folds on itself. This is what I refereed to as an elastic action. If you
knew what the hell the shelve is doing you wouldn't be jumping to WRONG
conclusions.

Your sail's foot is only supported at the TACK and CLEW. You have the
same support as you would have if the sail was REEFED. There would be no
support from the Folded Part of the sail. That is the best example I can
think of right now.

Neal, your new main IS A FREE FOOTED sail/ with a shelve. Why can't you
understand that a shelve give no more support to the foot of the sail
than the reefed section of the sail


http://community.webtv.net/tassail/ThomsHomePage

Comments to help assist you in overcoming your misconceptions are
interspersed below.


"Thom Stewart" wrote in message ...
Well Neal,

You're proven you inability to accept the truth about the action of a
"Wing Keel", the fact of a low profile PH, the advantage of a furler on
a cruising boat, and now the actual operation of your own Main Sail. The
scope of your known ignorance continues to grow. Explanation seems
hopeless.

You don't have a wing keel. You have a keel with end plates. In order for
it to be a wing keel the end plates must have a NACA foil section to them.
You have silly flat plates that are NOT wings.


I will try, once again, to enlighten you. Your SHELVE, it has excess
material so that as the foot of the sail forms its curve there is no
resistance applied by the shelve.

No resistance? Is that why the mainsail will stay put even if their
is only an aft force placed on the clew? If your argument was correct
the sail would also need downward force at the clew. Make no mistake,
a shelf-footed sail with a boltrope in the boom has it's shape maintained
by the foot and clew and not the clew alone as you suggest.

As you flatten your sail, the shelve
folds on itself. This is what I refereed to as an elastic action. If you
knew what the hell the shelve is doing you wouldn't be jumping to WRONG
conclusions.

I don't jump to wrong conclusions. It is presumptious of you to assume
you know more about my mainsail that I know about it. But, the do say
old farts get set in their ways so I forgive you your ignorance and
haughtiness.

Your sail's foot is only supported at the TACK and CLEW. You have the
same support as you would have if the sail was REEFED. There would be no
support from the Folded Part of the sail. That is the best example I can
think of right now.

Wrong, again. The foot is supported by the bolt rope as well as by the clew.
Do you forget all about air pressure?

Neal, your new main IS A FREE FOOTED sail/ with a shelve. Why can't you
understand that a shelve give no more support to the foot of the sail
than the reefed section of the sail

Why can't you understand you are looking it the entire picture and seeing
only a few pixels?

CN

OK Neal,

You've proven your point of ignorance. I admit to my inability to show
you the obvious. This is rather like your insisting
on the air being heavier in a Low Pressure Area because of the moisture
(G) I failed to show you the error of your way there also. I still try
but I'm learning to call it quits after trying

If your happy; so be it!

OT


http://community.webtv.net/tassail/ThomsHomePage

"Capt. Neal®" wrote in message

I'm not sure you understand MY shelf-footed main. It has no elastic
material
comprising the shelf. It has the same 6.9oz Dacron as the rest of the
sail. It
is the shape of the panel that constitutes the shelf foot that gives it
it's shape.

Only when the outhaul is set such that the sail can belly out to the extent
allowed by the shelf foot. Tighten the outhaul, and the shelf foot becomes a
loose 'bag' along the boom.

If I desired to pull my outhaul all the way out so the sail is flat then
why would I bother having a shelf foot. The shape of the main is
optimal with the shelf in place.

CN


"Wally" wrote in message . ..
"Capt. Neal®" wrote in message

I'm not sure you understand MY shelf-footed main. It has no elastic
material
comprising the shelf. It has the same 6.9oz Dacron as the rest of the
sail. It
is the shape of the panel that constitutes the shelf foot that gives it
it's shape.

Only when the outhaul is set such that the sail can belly out to the extent
allowed by the shelf foot. Tighten the outhaul, and the shelf foot becomes a
loose 'bag' along the boom.

"Capt. Neal®" wrote in message

If I desired to pull my outhaul all the way out so the sail is flat then
why would I bother having a shelf foot. The shape of the main is
optimal with the shelf in place.

I thought the idea was to use the outhaul to flatten the main in heavy wind;
and let it out for more belly in light wind.

That may be a racing mentality but for cruisers, one reefs in heavy wind.

CN


"Wally" wrote in message . ..
"Capt. Neal®" wrote in message

If I desired to pull my outhaul all the way out so the sail is flat then
why would I bother having a shelf foot. The shape of the main is
optimal with the shelf in place.

I thought the idea was to use the outhaul to flatten the main in heavy wind;
and let it out for more belly in light wind.

"Capt. Neal®" wrote in message

That may be a racing mentality but for cruisers, one reefs in heavy wind.

So, short of reefing, you're saying that there's only one required sail
shape for everythng up to, say, 20 knots, regardles of point of sailing? And
that the outhaul is redundant insofar as it offers adjustment of the sail's
belly?

Wally,

Neal may not move the outhaul because he doesn't want add any stress to
that Clew corner and the skimpy stitching. I can see his point but I
don't think it will help in the long run.

Ole Thom


http://community.webtv.net/tassail/ThomsHomePage