The use of lost wax process to obtain prototypes representative of zinc alloys die cast parts is described. The set-up for the rapid prototyping unit consist of a stereolithographic production of the part, with automated creation of the mold and casting of the alloy, all linked together with human intervention. Lost wax process is a foundry process, involving metal solidification and cheap and easy to handle materials for both model making and mold creation. Lostwax also produces better surface appearance, reducing the need for further surface finishing