- Buy Plaster of Paris, play sand, a 5 gallon bucket made of steel, a 2.5 qt bucket made of plastic, two U bolts, a hair dryer, one inch steel piping that is 2 feet long, a fire extinguisher, two eye hole screws, .75 inch pvc piping, one t-joint made of pvc, one homer bucket, two pvc couplings, and four elbow joints of pvc piping.
- Mix 21 cups of plaster of paris with 21 cups of play sand and add 15 cups of water in the metal bucket, mix well and let it sit for 13 minutes
- Place 2.5 quart bucket filled with water inside of the metal bucket mix after it has settled a bit and be careful not to mix in additional water, this will raise the mix level and leave a well after the mix harden.
- After it dries, remove the plastic bucket with channel locks.
- Take your fire extinguisher and decompress the material in it then remove all parts to leave just the metal capsule, then cut the top off with a hack saw or reciprocating saw where it's convenient and weld on the two eye hook screws to be opposite from each other so the holes line up.
- Take a 1.75 inch hole saw to drill two holes opposite from each other through the metal bucket at a 30 degree downward angle.
- Cut the metal pipe in half for two 1 ft pipes and attach PVC couplings, Next take your hair dryer and attach it to a pvc pipe which is attached to the middle hole of the T fitting which can then be attached to the metal PVC attachments by using the elbow fittings and some additional PVC piping.
- Next mix 10 cups plaster of Paris and 10 cups of play sand with 7 cups of water in the homer bucket and place the U bolts upright in the mix with some space between the two. Remove after it hardens from the bucket and cut a hole in it a bit larger than the fire extinguisher crucible you made earlier.
- Now you can place the fire extinguisher in the foundry after lining the inside with charcoal and place the top over it to keep the head inside. The hairdryer ventilation will be powerful enough to fuel the fire and keep track of the charcoal level to keep the fire hot, after melting a few dozen cans you can pour the molten aluminum into a cupcake tray to mold conveniently sized ingots.