I'm Doing It Now
Mark: I asked the same question a few weeks ago in this fourm relative to my C-22. Catalina Direct does sell kits to do what you are asking for the C-22, and they seem reasonable for what they are selling. They probably also offer a kit for the C-25. I only wanted to change the jib sheet, not the main and the jib sheet, so I decided to make my own sheaves out of delrin. I have a little lathe and it wasn't much of a problem. The original sheaves were made for 1/8 inch diameter S.S. wire (for the C-22). Catalina Direct uses 1/4 inch diameter line, very high tensile strenght, for their kit. What I did was use 5/16 diameter line,(Sta-Set X)and made the two sheaves for the jib halyard wider, to corespond to this diameter line. I changed the thickness of the aluminum spacer that separates the main and jib halyard sheaves, to .025 thick Stainless Steel, from 1/8 inch aluminum. This is where I picked-up the extra room for the larger diameter line. I used the existing main sheaves. I really don't have any problem with the wire halyard for the main, so this solution seemed to make the most economical sense to me. Aldo