On Tue, 06 Mar 2012 18:24:11 -0500, Wes
wrote:

Ed Huntress wrote:

Well, I never got a decent finish, it was so bad you could ridges across the item I
turned. I tried a different carbide insert and it wasn't any better.

By "ridges across," you mean chatter-type? Or was your tool-nose
radius too small for your feedrate?

I was within the nose radius. I tried 0.001 to 0.002 ipr.

If it's chatter, you know what things can cause that.

This is a very solid machine. 22" chuck, 4" dia quill in tail stock, uses 1" sq tool
holders. This should have been cake.

Wes

Well, someone else may have more specific ideas, but when it's
chatter, the short answer is that you have too much drag for the
rigidity of the setup, or you've had the bad luck to hit the right
frequencies for a sympathetic vibration.

The former is much more likely. I think the thing to do is to start at
the tool tip and work your way out from there. Tool nose sharpness?
Rake angle? Relief? Too much of the tool in the cut? Insert clamp?

You know the drill. Good luck.

--
Ed Huntress