Abstract: A matched mold curing apparatus defining a molding cavity has two sets of layers of curable, fiber-reinforced, thermosetting composite material laminated on a lower forming tool and upper forming tool. Closed-cell foam core segments are provided and placed adjacent to each other on the layers. The core segments are oversized with respect to the nominal size determined by the molding cavity in the closed condition, minus the thickness of the layers of composite material. A controlled temperature is applied firstly to allow plastic deformation of the core segments, but without closing completely the matched mold. The temperature and pressure are then applied to cause complete closure of the matched mold and curing of the laminated layers.