Good sources for learning basics/My basic Questions

[Hawkeye]

As the guys have said, beverage cans aren't the greatest source of aluminum. Generally speaking, the best source of metal for a given task is to use an item that was made the same way. For casting aluminum, melt down something that was originally cast. That metal will have the right added metals (such as zinc, etc.) to cast well. I started out melting down aluminum electrical cable, which is pure aluminum. Really nasty to machine.

I've had success with wooden patterns forming green sand, as Stan mentioned. I even made a replacement handwheel for my bandsaw by using the broken plastic wheel as the pattern. Another method that's worked for me is Lost Foam Casting - you carve the pattern out of insulting foam and coat it in drywall plaster. After it dries completely, you can sink it into a bucket of sand, using a controlled flow of air to liquify the sand. When you pour the molten metal into it, the foam burns out and is replaced by the aluminum. Do it outdoor, with a bit of a breeze (or a fan) to blow the chemical smoke away. Search Lost Foam Casting. There is plenty of information out there.

And take Stan's advice seriously. Plan for the what if's. Leather boots, heavy gloves, no synthetics, face and eye protection.