....the brass wouldn't ball up. All it seemed to do was turn into a
steaming mass of burnt metal.
Augest, are you applying flux to the brass before heating? It needs
to be fluxed. The black flux for brazing is best, but the white flux
for silver soldering also works. I regularly form little balls on the
fluxed ends of 16-, 18-, 20-, and 22-gauge wires with my acetylene
torch (even with a butane torch, for the smaller-diameter wires).
I don’t agree that brass fumes “are highly toxic.” If you overheat
brass, the zinc will fume off, and that’s not good for you, but I
would guess that the fumes from the flux are more dangerous, so be
sure to wear a mask for fumes or use a good exhaust system (or both).