Capri 14.2 Mast Head Pulley (Sheave)

Steve Rose

Member
I needed to replace my badly damaged mast head pulley, but could not find a suitable candidate. So, I sketched one (attached). If anyone is interested in a lathe/milling machine project, this would be fun.

However, I found a pulley and bearing on McMaster.com that I installed on my mast.
Diameter 3-1/2" Pulley: 9466T64 ($7.75)
Diameter 5/16" Bronze Bearing: 6391K405 ($1.25)

Press the bronze bearing inside the bearing that is molded into the pulley.
 

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I needed to replace my badly damaged mast head pulley, but could not find a suitable candidate. So, I sketched one (attached). If anyone is interested in a lathe/milling machine project, this would be fun.

However, I found a pulley and bearing on McMaster.com that I installed on my mast.
Diameter 3-1/2" Pulley: 9466T64 ($7.75)
Diameter 5/16" Bronze Bearing: 6391K405 ($1.25)

Press the bronze bearing inside the bearing that is molded into the pulley.
I needed to replace my badly damaged mast head pulley, but could not find a suitable candidate. So, I sketched one (attached). If anyone is interested in a lathe/milling machine project, this would be fun.

However, I found a pulley and bearing on McMaster.com that I installed on my mast.
Diameter 3-1/2" Pulley: 9466T64 ($7.75)
Diameter 5/16" Bronze Bearing: 6391K405 ($1.25)

Press the bronze bearing inside the bearing that is molded into the pulley.

Or you can order one from Catalina Direct, Product #: J1422, $26.92. See http://www.catalinadirect.com/index.cfm?fuseaction=product.display&product_ID=1795&ParentCat=443 ... a bit more expensive than your rig but made to order. Catalina Yachts is pretty good about repair parts availability for their boats.
 
That looks like the same design that I replaced. The inner diameter (bearing surface) is plastic; mine was worn and had radial cracks emanating from the axis. I expect that the bronze bearing will provide better service.
 
Thanks for the outstanding suggestion Steve! The McMaster pulley was installed this afternoon and worked remarkably. ~$12 with S/H total for a brilliant solution that rolls noticeably smoother on the brass bearing than the standard plastic and the nylon material was apparently intended for wire cables and feels more durable than the Catalina version (not that the Catalina pulley didn't perform well for a bazillion years).

I included some photos of the new pulley if folks wanted to see it in action, although I should have popped a pic before I bolted it back in. I finally had to give up on the old pulley because enough of it had cracked to let the halyard slip in between the pulley and mast which nearly sheared through the halyard.

Thanks again, great replacement idea!

Chris & Tammy


IMG_20151204_102808538.jpg IMG_20151204_102856737_HDR.jpg IMG_20151204_103131746.jpg
 
I used the info here to buy a McMaster sheave and bronze bearing. Total came to around $17 including S/H/tax (they used UPS). The one from Catalina direct is now up to $27+S/H/tax, so it is a decent savings. The quality is nice, but perhaps it is too precise. The new one is a very tight fit due to the width of the press in bearing. The extra width caused it to jam going into the aluminum mast slot. I eventually pressed it through with some steady pressure. After that, I also found that the original metal work in the extrusion and bolt holes were not that precise. It caused the new sheave to sit slightly off-axis, so it rubs a bit on the edge of the front and back of the slot. However, it works better than the original and I think it will eventually wear in and roll smoother. The old sheave was very sloppy on the bolt, but that was all plastic. Hopefully the bronze bearing wears in a bit to allow some axis movement.
 

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