I'm trying to restore an older Thistle and the mast is missing the entire sheave assembly for the main halyard. It's a silver aluminum mast but I'm unsure of the brand. If anyone has a clear photo of the masthead area showing how the sheave is installed, that would really help. TIA.
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Missing main halyard sheave assembly
- Thread starter DING!
- Start date
We encountered the same issue, my old friend and I, when we were trying to restore his '68 Thistle, the way it was, the mast was missing the sheave and the old mounting holes were barely visible, it turned out to be a Dwyer DM-375 mast, and the sheave sat inside a slotted bracket held in with a single pin, if yours looks anything like that, you might be able to retrofit with a standard Delrin sheave and stainless pin from a marine supply, I'll try to dig up a photo of mine if that helpsI'm trying to restore an older Thistle and the mast is missing the entire sheave assembly for the main halyard. It's a silver aluminum mast but I'm unsure of the brand. If anyone has a clear photo of the masthead area showing how the sheave is installed, that would really help. TIA.
Worst case, you can fab something simple with a side mount block to get sailing until you find the exact part
WhimsySailor
Member
- Joined
- May 9, 2025
- Messages
- 5
Missing masthead sheave on a Thistle? my buddy had the same problem, just last weekend lol.I'm trying to restore an older Thistle and the mast is missing the entire sheave assembly for the main halyard. It's a silver aluminum mast but I'm unsure of the brand. If anyone has a clear photo of the masthead area showing how the sheave is installed, that would really help. TIA.
You're probably looking for an internal sheave box. Check for any faint manufacturer stamps on the mast. Then hit up Thistle class suppliers like Great Midwest Yacht Company or West Coast Sailing – they often have these specific parts or diagrams.
block head
Member
- Joined
- Aug 16, 2025
- Messages
- 7
I ran into that same issue restoring my old Thistle, mast was missing the sheave setup completely. I finally tracked photos down through the class association forums, and that helped me fabricate a replacement that worked perfectly, it is worth checking there