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post #7 of Old 10-04-2007
Helms ALee!
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And now for a more helpful post. This is from the bizzarro AFOC tenuki school of sail trim, so be prepared for a bit of strangeness and undoubtedly some inaccuracies.

Sail trim for the blind, deaf and dumb, literally:

Hold the tiller in your hand, strike a steady course to windward take a couple of deep breaths, feel the movement of the boat through your seat, then close your eyes. That's right. Feel the tiller in your hand. How does it feel?

- inert, ie totally neutral. ok, you need at least some weather helm, get more sail power aft. power up the main and depower the jib/genny.

- lee helm - ok, problems here, you need to move sail power aft now! same sorts of stuff as neutral helm but more drastic

- strong weather helm, boat is fighting you - time to move sail power forward! depower main now, and maybe power up genny if appropriate.

- strong lee helm - ok, you must reef or drop that jib/jenny now! oops, you forgot to raise the main, do that now.

- light weather helm, boat feels responsive and in control - smile you are in the fast lane. Now open your eyes, you're gonna hit that DUCK!!

other points of sail have their own special subtly, but they can all be deduced with your eyes closed. start there, a balanced boat is a happy and fast boat. the balance shows at the tiller.


Wacked notes on 'sail power'. (this is just to set down a point of departure for the conversation - kibitzers join in!) for example: increasing sailpower in the genny moves the total sail power foward. here are the effects of the control on the sail power of the sail they control.

Main (aft power)
outhaul ( tightening - | ease + )
sheet ( tightening + | ease - )
traveler ( to windward + | to leeward - )
cunningham ( tighten - | ease + )
vang ( tighten - | ease + )
reef ( in - | out + )
halyard ( tighten - | ease + | drop -- | raise ++ )

Genny (fore power)
sheet ( tighten + | ease - )
reef ( in - | out + )
halyard ( tighten - | ease + | drop -- | raise ++ )

Crew weight effect on balance

goes in direction opposite of the movement of power, ie
you need to move sail power aft, move crew weight fore.


So, which control do you use once you figure out what you need to do to balance? Easiest way is probably to look at the sail shape, the telltales, etc. To really understand how boat balance works in relationship to sail trim you need to spend serious time sailing without using the tiller, either lash it down or let it swing free. everything starts and ends at the tiller IMHO.

Hope that is useful or at least starts a good argument!

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Last edited by tenuki; 10-04-2007 at 09:46 PM.
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