Hi Denis, Please see below additional information on this demo. Thanks! Material was 4140 Raw bar stock was 2.75” diameter and 14” long Rough Cutting speed - 800 SFM Rough Cutting feed - 0.040” PER REV Semi finish Cutting speed - 1000 SFM Semi finish Cutting feed - 0.030” PER REV Finish Cutting speed - 1200 SFM Finish Cutting feed - 0.012” PER REV
M8 on coolant . M9 off coolant . maybe it use carbide insert for OD operation . and this process is name Backturn process . because it not starting from tailstock to jaws , but starting at jaws to tailstock .