A question about turning aluminium

[uk trucker]

Yep, hss tools are the best for aluminium, the carbide ones tend to gouge it out rather than remove material by cutting. Watch out that the ally does not attach itself to the end of the tool if you feed it too fast, several light cuts are better than one heavy cut , in my experience.
My lathe is an EMCO Unimat 4 which forces me to treat it gently because its only small.

[FlyingBeagle]

What does SFM stand for? I gather that it is referring to a feed rate, but what does the abbreviation actually mean.