Cunningham Purchase Survey

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Quinn McCarthy
Posts: 84
Joined: Fri Jan 17, 2003 12:12 pm
Location: International Falls, MN

Cunningham Purchase Survey

Post by Quinn McCarthy »

I am just curious as to what purchase people are using on their cunninghams. Our new boat came with a 3:1 or 6:1 purchase if you go through the grommet and down to the mast base. Is 6:1 over kill? Could you damage the sails if you had a 6:1 CH and got carried away?

Thanks much.

Quinn
~~~~~Quinn McCarthy~~~~~
~~~~-Born 2 Run #545-~~~~
Tom Line
Posts: 137
Joined: Mon Jan 13, 2003 10:32 pm

Re: Cunningham Purchase Survey

Post by Tom Line »

Sail trim is always opinion of course, but on the 7.9 with a Boston D4 mainsail, I rarely use the cunningham. The primary purpose of the cunningham is to tension the luff of the sail, which is the one of the primary controls to set the fore-aft location of the maximum draft.

Assuming you have your halyard at the correct tension (maximum draft should be around 50-55% back in the sail, 35-45% in the genoa fyi), there's not much to be done with the cunningham. I have mine with a 2:1 purchase (tied to one side of the mast, through the mainsail grommet, then led aft) and I've never needed more than that.
Last edited by Tom Line on Mon May 04, 2009 12:13 pm, edited 1 time in total.
Tom Line
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dave
Posts: 727
Joined: Fri Jan 02, 2004 10:39 pm
Location: Little Rock

Re: Cunningham Purchase Survey

Post by dave »

I concur on that even with Dacron. The cunningham is the most overused and abused control on most boats. Leave it alone or use very sparingly and you will point higher and be faster than doing the opposite.
Last edited by dave on Sun May 31, 2009 9:58 pm, edited 1 time in total.
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Tim Bosma
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Re: Cunningham Purchase Survey

Post by Tim Bosma »

our cunningham runs up from the ring on the gooseneck down through a hook that goes in the luff tab and ends in a block, the next part runs from the base of the mast up through the block, down and is lead back on the cabin top. this gives us a 4:1. our main is raised up to max hoist, then eased a schosh when set up for lighter air, then if the air builds, an adjustment is called for by the main trimmer. not too much, though.
Tim Bosma, Bosun
Hot Tamale Racing
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S2 7.9's : #477
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