Reddit mentions of ComposiMold (Original) 40oz. Reusable Molding Material, re-heat to re-use!

Couple suggestions

1. Your molds are waaaaaaay bigger than they need to be.
   
2. If you have legos they make awesome mold walls
   
3. Glue your fig to the side of the wall. This can give you a lot more control over where your seam is placed.
   
4. Paint the fig in mold material before pouring. This ensures bubbles aren't on the surface of the figs.
   
5. When you pour, do half way and clean up excess with an exacto. The goal is a clean line. This is really more important if you plan on doing a lot of casts.
   
6. after one side cures, coat it in mold release, paint and pour the other half. If you do this right the two will just pull apart.
   
7. Once you'r done here you can lube up the legos and use it to stabilize the mold when you pour copies. With thinner wall this becomes really useful.
   
   If you're doing one time molds its really easier to use stuff like this
   
   https://www.amazon.com/ComposiMold-Original-Reusable-Molding-Material/dp/B0096BNE9S
   
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   There are a lot of varieties, but basically heat it up and squish around your fig, cut it out and then use it for the cast, or squeeze two part epoxy in there, etc.

It's a resin cast.

1. I took off the window handle and made a mold of the top of it. (used this stuff)
   
2. I poured wax into the mold. The first time I tried this I didn't let the mold cool enough and the hot wax melted the mold and fused to it, but I was able to cut out the fused bits and remelt and recast.
   
   
3. I stuck the wax blank down to the lid of a small plastic container I got from the dollar store.
   
   
4. I made two holes in the bottom of the container. One in the center to
   push the drill bit through, and one at the edge to pour the resin in.
   
   
5. I used some of this resin that I'd had left over from a tabletop.