Compression molding of composite parts on hot mold surfaces with a short cycle time

A molding system is provided comprising a cold mold with a large thermal mass and contoured thin mold inserts (15,17) with a low thermal mass. A composite sheet blank (11) of glass fibers in a thermoplastic matrix resin is placed between the inserts, heated and then transported to the cold mold. The composite sheet is pressed in the cold mold between the mold inserts to flow form and then cool the part. The mold inserts keep the surfaces of the composite sheet hot during the forming process, thereby enabling the matrix resin to flow and form smooth surfaces.