Our favorite tip has to do with the way [Eric] makes this a reusable two-part mold, which is more akin to injection molding. To pour silicone for the second part and get it to separately nicely ...

A release agent consisting of petroleum jelly and naphtha is added wherever the two sides of ... to allow the resin part to cure. While pouring the silicone for the molds, the mold box is placed ...