Step 4: Gang Mold
This mold is simply a slightly more complex version of your block mold. Start with several rectangles of foamcore. Adhere them to the mold board, and then spray them with a sealant or shellac. Then glue down your parts with a daub of hot glue, this makes things a little simpler to arrange and cast. Fill this mold with silicone exactly as prescribed in the previous step.