A method and apparatus for shaping, compacting, and supporting a composite material (C) contained between two flexible membranes (G, F) and capable of being stretched over a porous mold (A) are described. The apparatus enables the use of inexpensive mold despite the high pressures used. A counter-mold (M) having the same characteristics as the mold can be used in certain instances. The equipment enables the use of a plurality of molds and counter-molds during one manufacturing cycle.