Newbie - poor auminium cutting, but why?

[m_c]

Thanks very much for taking the time to input!

The end mills are new but I did run with a slow feed speed and a fast RPM. I oiled the surface to try to prevent sticking - but your comment makes a lot of sense. It's a bit dark and cold in the shed at the moment, but I will look at the mill tomorrow, and perhaps try a faster feed and a slower rpm....

So you essentially tried rubbing/melting your way through the material.
Cutting any kind of material is all about ensuring you take a suitably sized cut. Too small a cut/feed, and you just end up with the cutter rubbing against the material, which causes it to heat up, melt and basically turn into a mess like what you managed.

I'd very much doubt any form of Shapeoko will manage to cut aluminium well, as they just don't have the rigidity.

To give some idea of required feeds in 6061 alu, Suggested feed rate for a 1mm two flute endmill is 100mm/min, at 10'000rpm, for slotting with a depth of cut of about 0.75mm
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