Abstract: An expanded polyolefin foam with uniform fine closed cells is produced by placing a pre-form of a heat-expandable polyolefin resin composition in a mold cavity of generally uniform depth and closed by a platen, heating the mold to a temperature above the blow activation temperature of the pre-form while constraining the pre-form against any expansion under heavy controlled pressure, and then after cooling of the thus treated pre-form, removing the same from the mold and heating to effect expansion thereof. The pre-form is in a solid form with a volume exceeding the volume of the mold by a controlled amount in the range of 0.1-1 percent. The area of the pre-form is such as to fit readily within the mold cavity and its thickness exceeds the mold depth so that as the mold is closed by the platen the excess volume of the pre-form extrudes out around the peripheral edge of the mold before activation of the blowing and cross-linking agents.

Abstract: A shock absorbing pad is formed of first and second interleaved constituent components of different hardness which are interleaved through the thickness of the pad for absorbing forces applied in the direction of the pad thickness. The pads are formed by die cutting interim pads from mats of the first and second materials with the pads comprising constituent components that are separable. The constituent components are separated and respectively associated with different constituent components formed of the other material to provide the desired pad formed of the two interleaved different materials.

Abstract: A positioning guide for accurately positioning and guiding lengths of elongated rubber, plastic and other resiliant stock material having a predominately cylindrical exterior surface configuration being fed along a feed path to a cutting machine having a rotary knive and a pair of endless drive belts flanking the feed path. The positioning guide is formed of an integral elongated plate-like body of a length greater than the span of the drive belts along the feed path having a straight guide bore extending therethrough of circular cross-section at its opposite end. The plate-like body has a width and thickness greater than the diameter of the guide bore at the ends and having a pair of opposite elongated flat-bottomed depressions each forming a relief cavity in top and bottom faces of a plate-like body for receiving the confronting reaches of the drive belts so that the stock material is exposed in the region of the depressions for driving and positioning contact with the confronting drive belt portions.