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Matt/Meribeth Pedersen
 
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Default Main halyard winch, 1sp. or 2sp?

Holy Cow. By that formula, the boat I race on with the 660 square foot
foretriangle (and it's a 12 ton boat to boot with lots of stability and big
loads) has winches about half the required size. We race with old
Barient 52s, and while short tacking with the #1 requires us to swap
out grinders on occasion, I don't think a 110 power ratio is what the
boat wants. I'd say something in the 60's would be better than what
we've got (the Barients were the biggest thing going when the boat
was built).

Use the formula Evan gave you (assume full foretriangle at about 30
knots) and go from there. Use a 35 pound load on the winch handle.
That gives you a 56 which is probably in the ballpark.

"Glenn Ashmore" wrote in message
...


Ryk wrote:


You need to check the page again. The recommendation is based on the
size of the *foretriangle*, not on the size of the headsail. My
*foretriangle* is just over 300 square feet and the Lewmar 46s are a
good match for the loads all the way from the blown out 150% down to
what some of my chums refer to as my "cocktail jib" (short hoist for
about 80% of the foretriangle area).


The foretriangle is what we are talking about. Acording to that formula
your 300 sq ft foretriangle needs a pair of 52s. My I = 58.8 and J =
17.25 so my foretriangle is about 507 sq ft. The formula comes up with
80+ which is obviously out of line.

I think the problem is the 6 factor. It is supposed to be a combination
of 30 knots of wind and all the friction load. It must have been chosen
by a winch salesman. :-)

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com