Please STOP using the torch!!!
Are you using acetylene only?
Or is this an oxy-acetylene setup?
Are you using your propane torch with acetylene? The orifice is much
too big for this and this might be why you are getting the “black sap
Just the opposite will happen if you try using an acetylene torch
with propane, the torch will not light! Or it will but the flame will
constantly go out!!!
If however you are using an acetylene torch with the gas then
perhaps you have a clogged filter.
Some torches have little filters over the orifice that get clogged
If, after a soaking in your ultrasonic, the torch still does this, I
would either return the torch where you got it, or if it is an older
torch, invest in a new one.
Please don’t take this as being rude, but, where do you live that
they “will” allow acetylene but not propane, usually its the other
Concerning the laws in your area, Is it a matter of the size of the
tank? I once lived in an area that would only allow two 1lb
disposable propane canisters indoors.
Anything larger was prohibited, Acetylene was completely off limits!
I wish you the best.