Greets…new here with a question about alignment issues on an older (Craftsman) contractor saw. I’ve been using it with fairly good results for years…last week the bearings went bad – bad enough that the arbor also had to be replaced. Sears sent me a new arbor with one of the 2 bearing included.

I had a local machine shop procure the 2nd bearing and press them both into the trunnion. I aligned the trunnion as best i could by placing a blade on, setting my miter gauge in the slot just touching the edge of one tooth at the front – then checking for the same ‘just touches’ on the same tooth at the back. Then i tightened the 6 trunnion bolts and took a look at how the blade spun.

It had a horrible ‘wobble’. I took the blade back off and put a micrometer on the arbor’s flange. The up-and-down looked fairly good but the side-to-side deviates by .008.

Here’s the stuff i don’t know:

Since putting the micrometer on the top of the flange shows < .002 deviation but placed on the face of the flange shows much, much more, haven’t i learned that the shaft itself is true, but that the face is poorly cast/ground/milled…whatever the process. Or can there be a different explanation?

I don’t have a great deal of experience using a micrometer (read: any) so if there are important ‘to-dos’ involved i might be part of the problem. But it seems fairly straight forward.

Also….just how serious _is .008 deviation? Showstopper or within tolerances for an admittedly < fine woodworker?

thx

–steve…