Concrete panel construction and mold

A mold for forming precast panels, said mold comprising:

• a mold body configured to impart a predetermined shape to a molded product formed therein, said body having a panel-forming component provided with a plurality of integral, flexible, elongated, partial side elements presenting the periphery of the body, each of said elements terminating at a longitudinal edge,
• a plurality of elongated, rigid side rails on respective elements longitudinally coextensive therewith, each of said side rails projecting from said longitudinal edge of the corresponding element and cooperating therewith to provide a sidewall of the mold body complementing said panel-forming component and presenting a continuous inwardly facing molding surface for forming the molded product, at least certain of said side rails having openings therethrough communicating with the interior of the mold body,
• a plurality of tapered holeformers received in corresponding openings of said side rails and extending into said mold body interior,
• a plurality of tapered recess formers mounted on respective interior ends of said holeformers and each having a substantially greater diameter than the associated holeformer,
• said sidewalls having end edges and the flexible elements thereof providing hinge means for swinging movement of the sidewalls on said component outwardly from normal, molding positions and away from a molded product within the mold body to permit said product to be withdrawn therefrom,
• the end edges of adjacent sidewalls defining closed corners of the body when said sidewalls are in their normal positions and, upon said outward swinging movement of the sidewalls, said end edges separating to cause said corners to open, and
• releasable means associated with said end edges for holding the corners closed to maintain the sidewalls in their normal positions during the molding process.