"jim rozen" wrote in message
...

Some of the postive rake, uncoated carbide inserts (with
formed-in chipbreakers) were *too* sharp when I was
turning nylon parts for a second job. It was common
practice to go and deliberately break the edge, with an
arkansas stone to prevent the material from chipping out
at high speeds and feed rates.

An Arkansas stone? On carbide? I'd think it would gouge the stone, no?

As for the positive rake, positive rake for what? Steel? Aluminum? And do
you keep a separate set of zero-rake tools for brass? Or is one supposed to
just cross his fingers that he doesn't have a crash?

I'm not arguing with you. I'm arguing with the idea of using carbide as your
basic tool material for hobby machining. I've used a lot of carbide over 30
years, and I wouldn't do it. Not on my South Bend, and not on a Chinese
lathe.

Ed Huntress