4 Flute vs. 6 Flute End Mills: The Ultimate Guide to Choosing the Right Tool for Hardened Materials
4 Flute vs 6 Flute End Mills for hardened steel (HRC40–55): real test data, surface finish, tool life, vibration and when to switch. PM Series 6 flute delivers 40–60% longer life and Ra 0.6–0.9μm on H13, 4140 and mold steel.