ball mill

[da physicist]

how do i make a ball mill the cheapest and most inexpensive way?

[insane_alien]

find an empty can, put some grinding media in it an rotate by hand would be the cheapest way.

[Phi for All]

If you can borrow a variable speed hand drill from a gullible relative, I'd drill a hole in that empty can, run a machine bolt through the hole using rubber washers and a matching nut on the bottom of the can. Put the end of the bolt into the drill's chuck, tighten and now you don't have to stand there rotating it by hand.

[InigoMontoya]

Rock tumblers are pretty cheap. Buy one on ebay or craigslist or similar.

 

Done.