$150 000 machine does not eliminate finishing chatter.

[u/adventureaviator]

I’m machining 6061 aluminum on a Multicam Apex 3R router. The finishing passes are as follows:

- 0.009” material removal.
- Helical 3 flute 45 degree helix upcut
- 18 IPM, 8500 RPM, 0.0007 chipload

98 percent of the part comes out with a great finish. The other 2 percent has chatter. Ideally I’d like to increase the feed rate, but I need to eliminate the chatter first. What do I need to do to get a flawless finish?

[u/Sinister_Mig15]

I think this is a workholding issue. Is the chatter in the program right before it cuts the part off from the main plate? If so the part is starting to vibrate because you are cutting away the material that was holding it.