WCD Bearing Blocks

[Cory]

Originally Posted by craigboez

The only CAM tensioners I've seen appear to be very difficult to machine on a manual mill and very custom. How do you approach the tensioner?

A cam could be square. Or you could sand a radius into it. It doesn't need to be as fancy as what we make, for example. You just need something with a non-constant radius. They don't even need to all be perfectly the same since you're not going to get the exact same tension across all your chain runs.

[wilful]

For our chain tensioner cams we used a ~1/4" thick piece of 3/4" or 1" (I don't remember which) steel shaft with a hole close to the edge and welded a #10/32 socket head alan bolt into the hole.

[Mark Sheridan]

Originally Posted by wilful

For our chain tensioner cams we used a ~1/4" thick piece of 3/4" or 1" (I don't remember which) steel shaft with a hole close to the edge and welded a #10/32 socket head alan bolt into the hole.

As a "customer" of 766, I can attest that these work well. We even discussed removing the cam after tensioning to save weight since the bearing blocks we use can grip the box tubing so well. The cam tensioner looks like a automotive Cam bolt. I could never find one small enough to work. I suppose this design could be improved by using an aluminum 1/4-20 bolt and a 1/4" thick piece of aluminum to save weight. I don't think the loads are high enough to wear out the aluminum bolt. Plus it is nice to have more area to weld to.