Abstract: A cross-support member extends between the opposed side panels of an inverted U-shaped boot insert to prevent the side panels from collapsing toward one another. The cross-support member may be a separate structural element which is associated with the inverted U-shaped boot insert, or may be formed as an integral part of the inverted U-shaped boot insert (e.g., by partially cutting out the cross-support member from at least one of the side panels and/or by affixing the cross-support member to an interior surface of at least one of the side panels). The cross-support member may itself include lateral stiffening panels of desired geometry (e.g., triangular, rectangular, etc.) which are preferably formed as an integral part of the cross-support member by folding a lateral section of the cross-support member angularly out of the cross-support member's plane.

Abstract: An injection mold device for forming an article such as footwear from a plastic material includes a two-part male die such as a boot last, a fabric liner covering the male die, and a split female die surrounding the male die in spaced relation and forming together therewith a mold cavity. Beyond the upper end of the cavity, liner retaining pins on the male die extend outwardly of the peripheral wall thereof for retaining the liner in place during the injection molding operation. One of the pins is mounted for retracting axial movement for disengaging the tip thereof from the liner, and such pin bears against a sloping bearing surface of a first removable male die part which facilitates such retracting movement upon a relative shifting of the parts. The other pins are rigidly mounted in the male die part and project into recesses of the female die having undercuts and grooves extending between the recesses and the mold cavity.