Thread: Mainsail Trim
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Old 07-20-2008
SEMIJim SEMIJim is offline
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Quote:
Originally Posted by mpwildeman View Post
NOW HERES the kicker. I was playing with her mainsail trim last weekend, I had a 3-4 on the beam and she was playing up again. So just as a laugh I let the main out until it started to luff (back of the main flapping like crazy), and what would happen SHE SPEEDS UP.
I know I'm relatively new to this and all, but I'm confused as to why anybody finds this surprising . Aren't those the common rules: "When in doubt, let it out" and that maximum performance out of the main is when it's just short of luffing?

Random thoughts from my studies and what little hands-on experience I have...

What happens when you trim the main back in just a bit--just to the point it stops luffing?

Is the sail actually luffing, or is it simply blown and that's the leach chattering? Does it have a leach line?

I've no idea how this works with in-mast furling, but on any sort of reach in the air you're talking about, I would expect little vang or mainsheet tension, light on the outhaul, hmmm... light on the hayard and little backstay . A very full main with lots of twist. (I'm sure somebody will correct me if I've any of that wrong .)

Perhaps the jib is too closed and/or too close-in and it's back-winding the main? (At 3-4 kts? *shrug*) As angelog suggested: Try on just the main alone.

As for the balance: Do you have any mast rake? Too much? Too little? You say "she doesn't feel right" on a reach, but in what way does she feel wrong?

In a couple places you mention "3-4." As in 3-4 kts of wind? Seriously? You have more patience than most .

Jim
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