ASA and PSIA Instructor
Join Date: Apr 2000
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I've never seen a rope clutch used on a mainsheet, I cant' say why not, nor quite provide an explanation for why not, but I would not use a clutch. The mainsheet is the one line on a boat most often played, ie.e repeatedly eased and trimmed, and a rope clutch is not good gear for such an application.
As to size, given the above statement I'd generally go with as large a size as cleanly fits in the sheaves. If the 1/2 fits cleanly I'd use that size again. While the 3/8 would probably be fine to carry the load, the crew's hands will like the 1/2 a lot more...
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