Anyone have any idea what sort of hardness value an Atlas milling arbor ought
to be? I started making one, and was planning on having it heat treated.
Probably would work okay without the heat treating, but in for a dime, in for a
dollar.
I made one out of oil hardening steel, and one out of 17-4, which is pretty
much limited to about Rc 44. Left a little material on for final grind, and
hope they come out reasonably straight. If anybody has a guess, I'd like to
hear it.

Best Regards
-Frank