Thread: Sail Trim
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cavelamb cavelamb is offline
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First recorded activity by BoatBanter: Dec 2006
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Default Sail Trim

Wilbur Hubbard wrote:
"CaveLamb" wrote in message
m...
CaveLamb wrote:
I have a brand new suit of sails.
I'm trying to learn how they are going to trim -
and/or if I need to have any changes made.

Yesterday, winds 23 to 15, under mainsail only...

I could get all three tell tails on the leach to stream
only as the luff started to shiver (sometimes fairly deep).

The sailmakers said that they had added some shape.
I'm wondering if this may mean too much belly in this sail.


Make that 13 to 15?



Next time don't do mainsail only. Use a headsail, too. 13 to 15 you should
be able to hank on a 120 or 130% genny. 100% without a doubt! As you know,
the two sails on a sloop work as a team. The slot effect comes into play and
this will allow the mainsail telltales to stream backwards, even the lowest
one, because of the increased velocity across the windward side of the
mainsail. Does the mainsail have a Cunningham cringle? If so you can flatten
it some with a downhaul on the Cunningham.

That lower telltale on the mainsail can be a touch nut to stream back. You
just might find the optimal is the upper telltales streaming back and the
lower one fluttering or going around forward into the low pressure area on
the leeward side of the main there the chord is longest and the air tends to
stagnate.


Wilbur Hubbard



Good points.

I'm studying the main first because of the new shape.
It really does have noticeably deeper camber.

And yes, absolutely, will look at it with the genny up before deciding
anything drastic.

The old main didn't do this. I could get all three streaming and not
be hanging on the edge of a luff.


This boat was designed with a full battened main.
Very flat (by comparison) with fine entry and exit slopes...
Also a pain in the butt sometimes.


The genoa, which I thought was 130% is actually 143%.
I'm hoping we will get to that today or tomorrow.

Film at eleven?



--

Richard Lamb
http://www.home.earthlink.net/~cavelamb
http://www.home.earthlink.net/~sv_temptress