I was threading a barrel today with a new tool holder and new HSS insert. After every pass I had Built Up Edge on the insert. Checked setup. Everything looks good. I tried speeds between 140-320 rpm. Infeed was between 2-12 thou. per pass. I tried my normal cutting fluids Ridgid and Supercut. I still had the same results. I had to stop and stone the insert before I made the last two passes to clean the threads up. The insert seemed as sharp as any I have used. Never had this happen before. Any ideas? Boe