Like I say do it in a couple of passes.

Make the treadmills dia bigger and you will only take a small amount of material away. Reduce the dia and you will start to take more material away.

Very simple

Quote Originally Posted by suesi34e View Post
Hi andy_con
I like the idea of the thread mills and thank you very much for you advice. I just hope I don't go wrong a break a tool I don't have too many of them!
Many thanks
Steve