See Notes about the instructions.
At first, I only used plaster when casting shoe soles for my dolls. It was simple and cheap, but the results are a bit too fragile, so you cannot have very thin soles or heels.
So, I decided to try casting metal. First, I needed moulds. I bought some silicone rubber and carved a couple of masters for making the moulds. These are Tiny Kitty size as the silicone rubber is expensive stuff and I wanted to get some practice before trying anything bigger.
Next, I placed each master inside a frame (made of cardboard), mixed the silicone rubber and hardener, and poured it in. And that was a bit messy as not all frames were as well sealed as I thought they were. Fortunately, the leaks were not very bad. Then I noticed that one master was not secured well enough to the cardboard on which the frame was placed, so it started to float and almost ruined the mould.
After the moulds had hardened, I removed the cardboard and cut the blocks from the middle (lengthwise). You need a very sharp knife for this. I found out that balsa is actually the best material for the master as it is so soft that you can cut it in half along with the mould.
The instructions said to leave the completed mould alone for 4-5 days before using it for the first time, so I waited until the next weekend.
Melting the casting metal was easy to do on a regular stove. I had bought a cheap stainless steel bowl for this purpose as I knew it could not be used for anything else after it was used for melting metal.
The first try was a disaster. I was too slow and the mould was only half-filled when the metal started to cool. Fortunately, with casting metal, you can melt your failures and try again. The picture shows the second attempt. As you can see, there is still empty space in the toe of the shoe.
The wedge sole was much easier to cast and succeeded in the first try. (This is the mould done with the "floating" master.)
Here is a finished pair of wedge soles after removing the excess metal with a pair of pincers and a file. Look also similar soles cast using plastic.
I managed to get the first type of sole correct on the third try (the leftmost sole in the picture), but then the next one was similar to the second try. Together, the unsuccessful soles form a pair of left and right shoe soles, even though the mould is a universal one (same for both feet).