Re: Dry machining aluminum



Metal Man Joe wrote:

I'm surprised you are sucessful at this. I've tried dry machining AL
(by accident), and any sort of reasonable feeds and speeds results in
molten AL flying up through the endmill flutes and creating quite a
mess.


The trick is that the aluminum stock needs to be kept cool. When machining
thin sections, that is impossible without SOMETHING (air, water, mist, oil,
whatever) to draw away the heat. Some alloys don't need to get very hot AT ALL,
to create that horrible blob. Even 120, certainly 150 F is enough to do you in.

If you can keep the tool plowing ahead, and not concentrate too much heat in
one spot, you can get away with it, as long as the tool stays sharp.

The risk of a ruined cutter and workpiece, as well as the coolant's ability
to extend cutter life, keeps me going back to flood coolant for anything
I'm going to be doing a lot of.

Jon

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