The type of insert may be the problem. I recently had to turn 5" diameter 304 stainless and my "normal" inserts just were not doing a good job. Talked to a tooling guy and got some Sumitomo inserts which cut that stuff like butter. The edges appeared to be much sharper than my other inserts and last a lot longer too. I'm hooked on the new inserts and won't go back to the cheap ones.??
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Bill From Socal
