Today I started melting down some lead pellets and casting them from molds I made. To make the molds I used two pieces of crumpled up aluminum foil and placed the object I want to copy between them. I then smashed the pieces together with a hammer then cut away an inlet to pour in the molten lead. I first made a ring just by using a piece of pipe I hammered into the foil, then I attempted to copy a key. Here is the result!
Unfortunately the key is to thick and so wont actually fit in the lock! Also, since its lead its really soft and bends easily... Also, the copy was not perfect either, and I had to file down some parts.
This is an attempt to make a home cast water-cooling block (from zinc). My roommate had this idea and I had the materials. Its gigantic. The copper tubing runs through the block several times and I will pump water with a small fountain pump form a bucket. I made the form from a soda can I cut up and bent into shape. The form deformed from the heat when I poured the zinc and so is not great. The top surface needs to be sanded down since bubbles formed while it was cooling. We have not actual tried this yet...