Pro tip: I switched from a 3/8 to a 1/4 inch end mill for finishing passes on aluminum and the chatter marks vanished overnight.

My lead says it's a waste of time and tool life, but the finish is so much smoother. Anyone else have a strong opinion on this?

3 comments

3 Comments

victor_lane602mo ago

Heard that smaller tools deflect less, is that it?

coleh512mo ago

Yeah @victor_lane60, read that smaller diameter means less flex.

ray64828d ago

Have you actually tried a high helix 1/4 inch end mill with a tiny stepover? That changed everything for me, not just the chatter but the whole surface finish. I was fighting with a 3/8 for months on some 6061 parts and the finish was always decent at best. Then I switched to a 1/4 with a polish grade coating and just took off like .005 per pass.... night and day. Your lead probably hasn't run a side by side comparison, because the tool life trade off is minimal if you bump up your feed a tick. I'd say stick with it, man, your parts will speak for themselves.