Patent ID: 6921503

Claim:
A method for constructing a fiber-reinforced polymer article with the use of a mold that has a mold cavity with a first cavity surface, comprising: placing a first spacer in the mold cavity, wherein said spacer has a mold-conforming first spacer surface that conforms to said first cavity surface, and wherein said spacer is thinner than said mold cavity to leave a free volume on a side of said spacer opposite said first cavity surface; placing foamable material in said free volume and allowing said foamable material to expand and push said spacer toward said first cavity surface and form a foam core; opening said mold and removing said spacer; establishing fibrous material in a spacer-formed volume previously occupied by said spacer, and closing said mold with said foam core lying in said free volume and substantially against said fibrous material; injecting a flowable polymer into said spacer-formed volume previously occupied by said spacer and around said fibrous material therein and allowing said resin to harden, and removing the article that comprises said fibrous material surrounded by said hardened polymer from said mold cavity.