Does anyone cut that fast?
What machine are you using? Nomad? SO3?
What end mills are you using? Coatings?
Which Al alloy are you talking about? 6061? 7xxx?
Me, I never use C3D numbers. I do them myself, starting with G-Wizard recommendations. I factor in deflection so my rates tend to be lower than some but I get a great finish.
I rough 6061T6 on the Nomad @ 20 IPM, 10K RPM using 2 flute, ZrN/TiB2 coated end mills. The Nomad cannot use 0.25" end mills effectively for metals. I don’t even suggest trying.
End mill materials, coatings and helix angles matter:
Please provide some details and we can provide some guidance.
I did try 12(@10krpm), 16, and 24 IPM. For me 12 IPM was the worst. It was VERY noisy/chattery.
Feeds and speeds has a solid basis in physics and mathematics. The feed rate and RPM must be coupled properly for the available spindle torque to obtain a clean and optimal result. Too slow a feed and the end mill may not be cutting anything… until a step occurs… and you get a racket.
Adding in deflection to the equations ensures that secondary and tertiary effects do not create problems… and tool life is improved.
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