He is designing his own chess set, and wants to make one set of
pieces out of brass, and one from iron. I've done a bit of work in
brass, but not a lot, and none in iron.
Good luck on finding iron these days. I hoarde wrought iron when I
can find it.
Brass will melt easily for casting, but you need to watch out for
zinc fumes, you’ll get heavy metal poisoning. The mildest form is
zinc flu, and lasts for 48 hours, the worst is death.
Steel (which I think your friend really wants) requires relatively
extreme temperatures to melt, so if you wanted to go down that
avenue I woudl suggest going to a foundry that does steel investment
If you just want to machine steel and brass… brass can be machined
using standard jewelry tools. Steel on the other hand requires
something a little more heavy duty.
If I were to machine a steel chess set, I would use stainless steel,
and get it cast professionally, or I’d do the rough work with an
angle grinder, then pretty up with a linnisher.