Butane should work, MAPP will be faster, acetylene faster yet. I haven't noticed that acetylene is smokey when used in proper mixtures, perhaps the equipment you used needed a tune-up. You could go really retro and use a small charcoal forge.
Bill
An air/acetylene torch will not be any dirtier than the other alternatives
since most produce a mixed flame immediately on igniting
(air is drawn in by Venturi effect of proper gas flow). Jewelers use it
because it is simple, cheap, and safe. (one regulator, hose and gas).
You might find the gas supply is more expensive with the other
alternatives, and the difference in safety factors is slight. (Also,
slightly more heat output than air/Mapp).