A small kiln or aluminum foundry to do at home with simple things. See it ! Very simple.
Step 1: Make Refractory Concrete
Make your own refractory concrete with sand, volcanic stone and cement.
Step 2: Put It in Bucket Reserving a Hole
A bucket have to be filled with the refractory concrete. After that you can reserved a hole to put air.
Step 3: UP to the Foundry
Make the lid of the foundry.
Step 4: FIRE XDDDDDD
After drying, it's time to put the fire on and to found aluminum !