Mold Shape Deposition Manufacturing (Mold SDM) is a Solid Freeform Fabrication technique for producing complex shaped fugitive wax molds. A variety of castable polymer and ceramic materials have been used to make parts from these molds. This paper describes the Mold SDM method and an automated mold building machine based on a commercial CNC mill. Process steps, material selection and equipment issues are explained. Alumina, silicon nitride, polyurethane and epoxy parts with feature sizes ranging from 0.5 to 30 mm will be shown, as well as preassembled mechanisms and multi-material parts.