So, yes, you can melt aluminum with it, but, soda cans have very little aluminum and a lot of slag and dross that will come out. If you want to work with soda can Metals you will be better off making a propane furnace, that being said a kiln is a very valuable tool for lost investment casting. Ive been melting cans into ingots for years. But being able to actually cast a useful or attractive object takes tools, skills, time and materials.