Milling aluminium (need help quickly)

[jrgen20]

Hello there feloow CNC operator. This is my first post so please be gentle.

I need to mill 2 track shaped slots in to a alumminium bar. The dimesions of the slots are: (in metric!!!) length - 84mm, width - 38mm, depth - 22.5mm. Since i never have had to cut aluminimu before i am usin a 33diameter mill with the capability of cutting 6mm in depth at a time (for rough cut) and a 12mm end mill for finish. Since i am not familiar with aluminium i have no idea what spindle speeds adn feed rates to use. The first program i made took about 35min to make the slots. My machine is a Quaser MV 154 P (9000-1m).

I have 8 details to make and i do not have the time to wait that long. PLease help me!

Jürgen

[Donkey Hotey]

What kind of aluminum?

How many flutes on the endmill?

Are you running flood coolant? Mist coolant? Blowing air on it? No coolant at all?

You should be able to get away with 0.05mm per tooth for the feed. The machine's rigidity limits the feedrate.

Your choice of coolant will limit your RPM and machining speeds. If you're running flood coolant, you should be able to get away with 7000 RPM. If you're only running compressed air, it's going to be around 1500 RPM.

At 1500 RPM, with a two flute endmill, that's 3000 cuts per minute. 0.05 times 3000 = 150mm / minute feedrate.

At 7000 RPM with a two flute endmill, that's 14000 cuts per minut. 0.05 times 14000 = 700mm / minute.