Processes for making metal prototype parts are described. The key steps of the invention include: making a computer aided design (CAD) file of the prototype part; modifying such file a first time to produce a file of a first mandrel upon which the part will be formed; modifying such file a second time to produce a second mandrel upon which a metal anode will be formed, the anode and first mandrel then being used in an electroplating process to form the prototype. Stereolithographic techniques are preferred for making the mandrels out of polymeric materials.