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Main Halyard Sheave


I recently removed the main halyard sheave from the top of the mast on Revolution, #526. It is aluminum, 6.75" in diameter, .5" thick, and has a 7/8" center hole in it. The hole has a brass or bronze bushing in it which reduces the ID to 5/8".

fit of 3/8" line on original sheave

This sheave has carried a wire rope for 25 years with little apparent wear. I am now changing to an all-rope (3/8") halyard, which the original sheave can handle without machining.

close-up of sheave groove

I also plan to have an extra aluminum sheave made up as a spare, and machined specifically for 3/8" rope. My machine shop will duplicate these at a cost of about $100.00 each. If anyone else is interested, I would be willing to arrange a volume purchase. For reference, I have attached photos of the sheave I removed from my mast.


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