The water hardened rod we bought
http://www.kbctools.com/can/Navigati...fm?PDFPage=800
doesn't state a tolerance. The oil harden version is +- 0.0005. So far my old school vernier has not detected any variance at all from listed size in the few measurements I have done. The problem must be the bearings (which I can only measure with a cheaper digital vernier). I never expected bearings to be materially and consistently on the small size. Not sure it is possible to do anything on the lathe with the surface hardened 5/16 except trash or bend it. Will try the emery cloth to see what happens but I noticed KBC sells oversize reamers. A few key oversize reamers might provide a long term solution. Bearings were 1603 2RS. We ordered by bearing # and BDI never provided a vendor or catalogue when we placed order. Only when delivered was vendor obvious.
If anyone knows for certain that reamers can be used on the bearings successfully, would appreciate the heads up. I know I once tried to use a drill as a reamer on a bearing by clamping the inner rotating assembing in a vice and using a portable drill. I am kind of hoping I can do the same with a reamer for a thousand or so.
I am much more in tune with measuring electrons versus 0.0005's ....
