Why does nobody talk about switching to a 4-flute endmill for aluminum?

We were running a job on our Haas VF2, milling 6061 parts, using a 3-flute endmill for years. The boss said it was 'good enough.' Last month I swapped in a 4-flute tool for a test run on the same program. The finish went from looking like a cat scratched it to almost a brushed look, and cycle time dropped by about 15 seconds per part. I think the extra flute just handled the chip load better. Has anyone else seen a jump like this just from changing flute count?

3 comments

3 Comments

dakotal161mo ago

Wait, 15 seconds faster? @grant_anderson is right, bosses hate free upgrades.

grant_anderson1mo ago

The boss is always the last to know. That extra flute gives you a better core, so you can push it harder without chatter. It's a free upgrade if your machine has the rpm. We saw similar gains on our old Fadal just by switching tooling brands.

james99519d ago

I read somewhere that 5-flute endmills are basically a cheat code for aluminum. The extra land gives you more stability, so you can step up your radial engagement without worrying about deflection. Worth testing if you've got the spindle speed to spare.