Replacing halyard sheaves

Sea Change

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I've been getting a lot of friction on my main halyard so decided to pull the sheaves and they seem pretty worn. Certainly the hole is much bigger than the pin!
How do I go about sourcing new ones? It's a 1988 Jeanneau Sun Kiss 47.
I'm currently in the US, but have family flying out from the UK in a couple of weeks of that helps.
 
If you post the diameter of the sheave it' thickness and the hole for the axial, that would help.
Additional information on the max rope diameter, and the length of the axial pin. That would help someone to specify it.
 
It's an old Francespar mast.
Everything is very worn so it's hard to be sure what size things are supposed to be. The pin is 12mm, sheave diameter about 80mm, thickness about 15mm.
 
If it's just the hole that has worn you can get the hold bored out and a bush fitted.

I bored out my mast head pullies and fitted some stainless sealed ball bearings in the pully that reduces the friction considerably

Any one local with a small lathe could do the job like a local machine shop
 
It's an old Francespar mast.
Everything is very worn so it's hard to be sure what size things are supposed to be. The pin is 12mm, sheave diameter about 80mm, thickness about 15mm.
Boat of similar age, when I replaced mine the rigger just opened a drawer and took off a couple of sheaves from a drawer full; I guess they are quite standard. There are also made in metal (not sure steel or light alloy).
 
Slight thread drift - my mast is down and Im r not at the boat, but pretty sure it’s a Selden (Sadler 29), how do you get the pin out to replace the sheave?
 
Slight thread drift - my mast is down and Im r not at the boat, but pretty sure it’s a Selden (Sadler 29), how do you get the pin out to replace the sheave?
Can't help with that, I'm afraid. Mine was simply a long clevis pin that serves as the axle for both sheaves.
Doing it at the masthead whilst afloat was... interesting.
 
Haven't managed to track down sheaves yet, but worst case scenario, I can buy a sheet of 15mm delrin for $15, and I have an 80mm hole saw and a 12mm drill bit.
Not sure how successful I will be in shaping the edge though.
 
View attachment 196100

I've been getting a lot of friction on my main halyard so decided to pull the sheaves and they seem pretty worn. Certainly the hole is much bigger than the pin!
How do I go about sourcing new ones? It's a 1988 Jeanneau Sun Kiss 47.
I'm currently in the US, but have family flying out from the UK in a couple of weeks of that helps.
Just take them to an engingering shop. They can make you new ones. I had brass bearings pressed into my new ones
 
Slight thread drift - my mast is down and Im r not at the boat, but pretty sure it’s a Selden (Sadler 29), how do you get the pin out to replace the sheave?
If Seldén post circa 1980, the head box can be lifted out of the mast extrusion once the two large nyloc nuts on top have been removed. The sheave pins can then easily be knocked out.
 
I was very surprised to see that at the sites that "Runagroundhard" and "Bignik" recommended there were no sheaves with bronze bushes.
Sheaves will naturally wear and are at inconvenient locations, so the most robust sheaves would be a good choice.
That means bronze bushes.
gary
1752495550233.jpeg
 
Z Spars have, as always, been very helpful and prompt. But they don't have the right size.

Waiting to hear from US Spars, who seem to be their US counterparts.

Rig Rite have the right size... at $99 (plus taxes and shipping) per sheave. Seems rather a lot! Would definitely have a go at making my own before I paid that.

I can get an equivalent part from a place in Denmark at €32, not sure what's involved getting that delivered to the US though...
 
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Sheaves will naturally wear and are at inconvenient locations, so the most robust sheaves would be a good choice.
That means bronze bushes.
gary
View attachment 196142

Even bronze bushes will ware when grit is introduced which I fitted my mast head and mast bottom sheave bearings with sealed stainless steel ball bearings.

S6201RS portant 12*32*10mm (10 PCS ) ABEC-3 440C acier inoxydable S 6201RS roulements à billes 6201 roulement à billes en acier inoxydable - AliExpress 18
 
Z Spars have, as always, been very helpful and prompt. But they don't have the right size.

Waiting to hear from US Spars, who seem to be their US counterparts.

Rig Rite have the right size... at $99 (plus taxes and shipping) per sheave. Seems rather a lot! Would definitely have a go at making my own before I paid that.

I can get an equivalent part from a place in Denmark at €32, not sure what's involved getting that delivered to the US though...
Who is it in Denmark? Ours eventually came from John Mast who are very efficient (but think close for a period for summer holidays)
 
Hi Roger.
How did you keep the ball bearings in place in the Delrin /Plastic sheaves?
Locktite or some other product?

gary
 
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