Yesterday I attempted to set up a charcoal furnace to melt aluminum. I have two brake drums from some huge trucks. The brake drum is my furnace and I have a huge cast iron pot for my crucible. I used my air compressor to feed air into the furnace.
The brake drum is resting on a 3/8" steel plate.
In this photo you can see the crucible. It is a cast iron pot I purchased at a junk shop. It probably holds a gallon which is huge amount of hot metal.
I put a grill in the bottom hoping to get charcoal under the crucible as well as surrounding it. I managed to burn 20 pounds of charcoal and melted a garbage bag full of cans.
I managed to dip out this 2.5 ounce blob of aluminum and pour it in my muffin pan mold. There was quite a bit more metal still in the crucible but I was loosing my heat.
I learned a great deal from this first pass. I manged this with no cover, no insulation and a poorly controlled air supply. I am sure I can do better.
Also in my rush I dipped out good metal with the dross. So I have to work on my techniques as well.