I have a Prestolite air acetylene torch which I use with a B tank. I
use it to fuse tiny jump rings, as well as for melting silver for
casting. I use the smaller tip for tiny work, and the big torch tip
It is very easy to use. I turn the black knob so that it opens to
the B section, which is fine for my work. To turn it on, I turn the
little wrench that is attached to the tank about a quarter of a turn.
Then I turn the knob on the torch handle so that the gas flows
through to the tip.
When You are finished just turn the gas off at the tank—turn the
wrench until the dial registers that it is off. Then I bleed the hose
to remove any gas which is in it. Some skip this step, but I prefer
to bleed it.
Hope this helps,.