I started casting because metal rods are expensive and I had scrap aluminium and brass. My furnace was a large uninsulated bucket. My crucible was the bottom half of a fire extinguisher. I used chunk charcoal and a hair dryer. Pipe was used for a mold. Surprisingly it worked well for aluminum. Next I tried brass. I melted the brass, the bottom of the fire extinguisher fell out and also burned up the bucket. Then I built a furnace out of a small hot water heater, 4" of insulation and a refractory cement coating, propane burner and a proper crucible. It worked really well casting copper and brass rods. Problem was the rods were so hard that I couldn't turn them. I posted the issue and asked for help under another heading. I look forward to being in the forum.
Welcome. I started with charcoal but now use waste oil, and sometimes propane. I also started with 1 lb propane cans for crucibles and got exactly the same failure(s) you describe. Charcoal is an effective fuel but its controlled use takes some practice. Too much air overall or in a concentrated area will unleash a destructive beast that will cut right through steel or even ruin a proper ceramic crucible. It's not so much a matter of too much heat, but too much oxygen. That's a topic for another day. At any rate, I'm glad you've joined us. Jump right in. Pete
Welcome! The alchemy that is alloys is something I have always been interested in. What makes one piece machine like butter and the next burns up a tool bit? Hopefully the answer to yours will help us all.
