If you can get another farmer out there in Nanawa to help you and split the drops, that would be optimal if you can't do these solo.

Really OP, the bombs in Copperbell aren't worth your time unless you're already L50, which I see by your info that you are. They do have about a 5%-10% higher drop rate than Nanawa if I remember right. Take a helper with you there as well, it's so much faster, and you can farm ants for the scales (scale glue) while waiting for bomb repops.

Unfortunately, steel has taken more of a front seat for BS in this patch, it's almost impossible to skip over it now. So if you are stuck in the dreaded 30's, you'll have to just suck it up and farm ash until 36-ish when you can start churning cobalt ingots.

FYI, if you think bomb ash is bad, try getting your hands on some aldgoat horns for any reason.