My adventures in backyard metal casting began in 2009 when I built a totally homemade blast furnace. It seems to work well and can run on propane, waste motor oil, waste vegetable oil, biodiesel, or just about any other flammable liquid or gas. The idea is that it should burn so hot and so completely that it produces no detectable smoke or odor when operating. I can say that this thing got extremely hot and had wonderful cyclone action. I planned to use the burner for other projects and not just metal casting, I am hoping it can be used to run a 55 gallon drum pasteurizer that I am still building, in fact this is really the primary reason I built the burner.