For some reason propane-air torches are not very available in the US
, Silver is mostly worked with propane -air in Mexico and torches are
available there. They are a copy of the European Sievert-Primis torch
that has 3 different burner heads a small flame, a medium flame and a
very large bushy flame good for annealing. Melting for casting is done
with Propane- Oxygen in Mexico. I have never run Across the Sievert
torch in the US but they seem to be available someplace:
I bought a system in Mexico and it works fine and was actually
cheap but they could use a little better quality control.
Acetylene has a density about 0.9 that of air a little lighter it
diffuses pretty well and does not linger in low pockets like propane
with a density about 1.5 times that of air.
Propane is not allowed for shipboard welding and cutting , Acetylene
I am not very fond of acetylene cylinders and I worked in that
industry for 35+ years and managed a number of Acetylene plants.
There were a lot of very old cylinders and some ratty valves. Some
vendors had good stuff and took good care of it some were terrible.
Its a people-business thing Since I retired there has been a change in
US regulation pertaining to propane and acetylene cylinders
regulating allowable age and requiring retesting. I haven’t seen the
regulation but it should improve things.
I personally do not like to see any flamework in a combustible
structure. A clean well ventilated work area, minimum inside gas
storage and good work practices such as careful leak testing and the
equipment safety procedures provided with the equipment. is
essential. With good cylinders and a leak free system fire problems
will start someplace else first.