Ran a test cut on some 6061 with a new 3/8 ball endmill and got a weird finish.

I was trying to take a 0.015 finishing pass at 150 IPM, but the surface came out looking almost wavy. My feeds and speeds were right for the tool, so I'm thinking maybe my machine's spindle bearings are starting to go. Anyone had a similar finish issue that turned out to be mechanical?

3 comments

3 Comments

drew_grant524mo ago

Could be a simple case of tool runout.

smith.anna4mo ago

Totally agree, that's the first thing I check. Had a job last week where the finish looked awful, just a tiny bit of runout in the collet was the whole problem. Swapped it out and the next part was perfect. It's amazing how such a small wobble can ruin everything.

hayden7202mo agoTop Commenter

Happened to me with a brand new carbide endmill that turned out to be out of round from the factory. Checked the runout on the tool itself before even putting it in the holder and it was already wobbling by a couple tenths. Swapped it for a different one from the same pack and the problem went away completely. Sometimes its not the holder or the collet but just a bad tool from the start.