[Joe_CNC]

I've been having a bit of a strange problem with 3 Flute High Helix Endmills designed for aluminum. They cut very nicely with less vibration than 2 or 4 flute endmills, but the bottom surface of the cut comes out rather rough compared to a 2 or 4 flute. The profiled walls of the cut are fine.

Specs:

Haas Super Mini Mill
0.5" HSS 3 flute high helix endmill for aluminum, Centercutting
4,000 rpm - 10,000 rpm (500 SFM - 1300 SFM)
15 - 75 ipm (.001 fpt - .005 fpt)
.075 - .15 Axial DOC

6061-T651 Aluminum

Has anyone else experienced this problem?

When I run at the same speeds/feeds with a standard helix 3 flute, the bottom surface is much better, but still not as good as a 2/4 flute.

Thanks,
Joe