For this project I used a couple types of Smooth-On products: Mold Max Stroke and Mold Max 30 along with GE Silicone I in tubes. The hard mother mold is made with Bondo and fiberglass resin. This piece of drift wood had holes that had to be filled slightly before molding. I decided to use a shallow fill to give me the option to either leave them filled or cut them out of the cast piece. The cast is not solid and can be filled with foam with a couple pieces of plywood inserted for attaching fish and hanger for wall.