Patent ID: 7632448

Claim:
A method of manufacturing a door, comprising: heating a wood fiber board blank to a thermo softening point such that the material of the blank is plastically deformable; placing the wood fiber board blank in a press comprising an upper mold and a lower mold, at least one of the upper mold and the lower mold movable toward the other from an open position for receiving the blank to a closed position defining a mold cavity; moving said at least one of the upper and lower molds towards the other into the closed position to provide the mold cavity with at least one constriction adapted to restrict lateral extrusion flow of the softened material of the blank, the constriction located in a relatively high strain area; heating at least one of the upper mold and the lower mold; pressing the blank in the mold cavity in a pressing cycle to form a first molded door skin, the pressing cycle comprising at least one deformation period in which pressure is applied to create strain in the blank, followed by at least one pressure reduction period in which the pressure is reduced without opening the mold cavity so that the upper and lower molds remain in close contact with opposite sides of the blank to convert water in the blank into steam which is allowed to escape from the mold cavity, followed by a pressure increase period; affixing the first molded door skin to a first side of a door frame; and affixing a second door skin to an opposite second side of the door frame.