Abstract: Molded fiber reinforced plastic (FRP) composite hinges and a method of making integral fiber hinges molded-in an FRP composite. After a mold surface has been prepared, a layer of fabric is placed against the mold surface, the fabric is impregnated with resin, and a hinge assembly is placed against the resin-impregnated fabric. The hinge assembly includes juxtaposed narrow strips of reinforcing fabric and fiber hinge fabric. The hinge fabric is composed of flexible fibers which are of high tensile strength and capable of repeated flexing without substantial fatigue (e.g. aramid fibers), and which form flexible elements along a desired hinge line in the molded composite. The hinge assembly also has an elongated wire between a strip of hinge fabric and an adjacent strip of reinforcing fabric, the wire being coextensive with the desired hinge line, and the fibers of the fiber hinge fabric extending across the desired hinge line.

Abstract: A vacuum bag molding apparatus for a mold having an inner molding surface and a peripheral edge with a vacuum pipe extending around the edge and connected by a series of vacuum ports to the inner molding surface inward of the edge, which includes a continuous channel member of metal or plastic and a spline member of metal or plastic which is receivable with a tight fit in the channel of the channel member to hold a flexible air-impervious sheet between the spline and the channel of the channel member to provide an air-tight vacuum bag which is evacuable through the vacuum ports of the mold to carry out a vacuum bag molding procedure. The sheet of flexible material, channel member, spline member and adhesive to secure the channel member to the edge of the mold may be supplied as a kit.