You were lucky with the stainless, some grades are not nice to machine.

Agree. There's nothing wrong with metal that cuts OK. Problem is plenty of alloys don't cut well, and some are horrible. Industry choose alloys for particular purposes, and often don't require it to be machinable. What turns up as scrap can be almost anything.

When I started with a lathe I had terrible problems – almost bad enough to put me off completely. Turned out my entire collection of scrap metal was unsuitable. Gummy aluminium, gritty steel, work-hardening stainless, pipes with super-hard welds, and other bad news. Almost by chance I bought some EN1A, which is a mild-steel specifically made to be easily machined. Suddenly the lathe worked properly!

Not realising a metal is difficult is very confusing. Experienced operators recognise difficult metal and adapt, but it's safer to learn how decent metal turns before trying to cut the difficult ones.

When things go wrong in the workshop people tend to blame the tool first. Then, maybe, the operator. (Many have touching faith in themselves, despite not having developed any skills yet!). It's easy to forget the material could be horrible. Now I understand tools and materials better most of my workshop problems are caused by me.

Dave