Method of molding a composite framed resin article

Claim 1

The method of making a molded body of predetermined shape comprising the steps of: providing a pair of vacuum molds having complementary molding surfaces, heating sheets of cellulose acetate butyrate to a moldable temperature and placing one sheet on each mold, evacuating the air from the area between said sheets and said molding surfaces to cause said sheets to conform to said molding surfaces and form complementary body portions, maintaining the air evacuated from said molds to retain the sheets in intimate engagement with said molding surfaces, applying moist resin and fiberglass to the exposed surfaces of said molded sheets to bond said fiberglass thereto, curing said resin and fiberglass, relieving the vacuum pressure within said molds to facilitate the removal of said body portions therefrom, connecting said complementary body portions in assembled relation, introducing a foamable polyurethane resin between said body portions, permitting said polyurethane resin to foam, and curing said foamed polyurethane resin, whereby said fiberglass permanently bonds to said body portions and seals the same to prevent a chemical reaction between the cellulose acetate butyrate and the polyurethane resin and said polyurethane resin foam permanently interlocks with said fiberglass to provide permanent buoyancy for said body.

Claim 2

The method of thermoforming and reinforcing a molded substantially rigid article to a substantially exact predetermined shape within close tolerances, comprising the steps of: providing a mold having a non-planar configuration-imparting surface, vacuum-applying means operatively associated with said surface, heating a thin sheet of normally rigid thermoplastic synthetic organic polymeric resin to a moldable temperature and applying the same to said mold with portions of said sheet in intimate engagement with said mold in a manner that the sheet will be drawn against said mold surface by vacuum, energizing said vacuum-applying means to evacuate the air from between said molding surface and one side of said sheet to cause at least said one side to conform to substantially the exact non-planar configuration of the surface of said mold, superimposing a reinforcing layer of fiberglass saturated with a polyester resin binder to the other side of said sheet while holding said one side in intimate engagement with and conforming to said non-planar molding surface by said vacuum, curing and hardening said resin binder while maintaining the vacuum between said sheet and said molding surface, releasing the vacuum to permit the removal of the reinforced molded article from the mold, and stripping said article from said mold, whereby said one side of said article retains the exact configuration of the molding surface and said sheet provides a coating for the reinforcing layer after the removal from the mold.