I'm a prototype model maker, specializing in RTV molding and casting. 3D printing is a great building block to create masters for molding. 3d Prints can be sanded and finished into perfect masters, then molded. Castings can be made in many different materials to achieve different effects. When I'm not casting, I like to finish and paint 3D printed models. I often modify them after printing, and make them into the models I would really like them to become.