Method of production of reinforced foam cores

Abstract

Rigid foam insulation boards and thin flexible fibrous sheets or strips are stacked in alternating layers with adhesive between the layers, and the stack is compressed while the adhesive cures to form a rectangular core panel or billet. In one embodiment, the parallel spaced sheets or strips extend diagonally of the panel or billet, and each billet is cut through the alternate layers of foam and fibrous sheets and along parallel spaced planes to form a plurality of core panels. The core panels are adhesively bonded between skins of rigid sheet materials to form laminated sandwich panels with the fibrous strips connecting the skins. The above stacking and curing steps are also performed with core panels in place of insulation boards to form a billet which is cut to form core panels with grid-like webs, and grid-like core panels are used to form a billet with the webs extending in X-Y-Z directions. Billets are also formed with core panels stacked in a step-like manner and then cut along inclined parallel planes to provide core panels with truss-like webs, and billets are formed with adjacent rigid foam boards having different densities and thicknesses, Resilient foam panels are used in place of or with the fibrous sheets for producing core panels which may be curved, and the foam between the webs of grid-like core panels is recessed to expose the webs for bonding surface materials such as stucco to the core panels.