We melted down about 200 soda cans in a brake drum last night in my welding class last night. Adding them into a pipe crucible placed into the bowl of the drum. Tongs just pulled off the non aluminum slag on top and we poured the pour aluminum into a form to make an ingot - like a gold bar but aluminum. Man was it fun.
The class instructor was pointing out the difference that these bowl shaped brake drum designs are more so considered a foundry. He has a swiveling lid that sits over top to better enclose the heat for forging but he was pretty insistent that "forges" have are enclosed and load from the side for the most part.
Sorry if I'm coming across like a know it all Poindexter, type...but, I was thinking of this thread when we were doing the aluminum work.
I'm gonna build me one of these in my class, soon. Hopefully next week.