Abstract: The top edge portions of a ski of plastic material are produced in a two-part mold by placing the bottom surface sheet and edge portions of the ski on the floor of the mold while preformed top edge portions carry the top surface sheet and are supported in the mold by an auxiliary strip which extends outwardly from its side surface and rests on two opposite walls of the mold box. The auxiliary strips are held in place by magnets lodged in the opposite mold walls while the mold is open. After closing the mold with the mold lid a plastic foam material in the mold is expanded to produce the ski core and bond together the top and bottom surface sheets and edge portions of the ski. The auxiliary strips are severed from the top edge portions to finish the ski.

Abstract: A rack for holding the sides of a flat-sided plastic napkin holder vertical while the bottom of the holder is being molded. The rack includes a wire basket of generally box-like shape with vertical sides and a bottom formed from segments of stiff wire. In addition to the wire basket, the rack includes a rectangular sheet of relatively stiff, resilient polyethylene which is held fast at the middle by the bottom of the basket frame so that the halves of the sheet extend upwardly and press outwardly against two of the basket sides to give it a U-shaped profile in side view. The wire basket has three short legs to support it firmly on the rim of a mold for casting the bottom of the napkin holder. To use the device, preformed sides of the plastic napkin holder are forced between the two halves of the polyethylene sheet and confronting sides of the wire basket so that the pressing halves of the sheet hold the napkin holder sides in position against the basket without slippage.

Abstract: A fixture for blocking lenses of various diametral sizes with cast blocks of corresponding diametral sizes using a single annular support of fixed diameter for all lenses as a reference relative to which pressure used in clamping of the lenses for blocking may be regulated to prevent lens distortion despite variations in their diametral sizes.

Abstract: A valve seat for a butterfly valve having an annular, rigid reinforcement ring embedded in a body of molded elastomeric material. The seat has a pair of diametrically aligned shaft openings for the valve disc supporting and actuating shaft. These holes extend through the elastomeric material and the reinforcement ring and, during molding of the elastomeric material, are occupied by removable cores which center the reinforcement ring about the cores between the end faces of the mold and position it concentrically between the inner and outer circumferential walls of the mold cavity. To prevent the reinforcement ring from rotating about the cores and to center it positively between the end faces of the mold, a pair of aligned pins are provided, one in each of the mold end faces, which clamp the reinforcement ring between them. These pins are located circumferentially along the reinforcement ring approximately halfway between the cores.

Abstract: The specification discloses a method of making an aperture-defining frame member, particularly a window-frame, comprising a rigid frame-shaped reinforcement made of e.g. a solid metal section embedded in synthetic resinous material. The method comprises placing the reinforcement in a mould cavity having the shape of the required frame member and locating the reinforcement in the cavity solely by engaging complementary interfitting formations on the reinforcement and on pin-like projections which extend from the cavity walls, e.g., recesses on the reinforcement engaging the ends of the projections. The longitudinal axes of all the projections are parallel to a predetermined plane and the engagement of the end of each projection with the complementary recess of the reinforcement prevents movement of the latter at least in first directions perpendicular to the plane. The projections are located around the reinforcement to prevent movement of the reinforcement in second directions parallel to the plane.