For casting, propane or a pot is the only way to go as you can easily control the tempurature. For melting weights, biodiesel (or for that matter, waste motor oil) is the only way to go. All I did was take an old aluminum skillet, an old aluminum pot, a concrete block broken in half, and some metal doo-ey-floppy to hold up the pot and it worked wonderfully, although it smokes like the devil. I figure I'm getting about 1 cup of biodiesel to every 8# bar of lead... if you used old oil, it would be free. It'd probably take at least one green cylinder of propane to accomplish the same thing... Lighting it can be a trick, just take some old rag and a propane torch and you should have no problem... takes a min, but once the oil is up to temp it really goes to burning good and it doesn't take long at all to melt down the weights.