A device for producing plates made of metal, plastic or a metallo-plastic composite material, including thermofusible, thermoplastic and thermosettable materials, by machining with a machining tool in a fast prototyping process, includes a plate mold integrated in the prototyping machine. The mold is adapted to receive a material matching the shape of the mold, and to subject the plate to a heating/cooling cycle using a heating/cooling device integrated in the mold body, and additionally includes a vat (2), a base plate (3), a heating circuit (4) and a fluid circulation circuit (5).