Abstract: A plug may be used in a receiver of a track system in order to prevent debris from filling the track. In order to keep the receiver clean, the plug preferably includes a generally planar base with a size of sufficient area to cover at least one receiver and prevent entry of debris into the track system. A mount prevents the plug from dislodging from the receiver. The mount includes a primary end with a primary clip and a secondary end with a secondary clip, each clip having a unique length. An overhang forms a space between the base and both the primary and secondary clips on opposing ends of the plug. The plug is positively retained in the receiver with an overhang on both the primary end and secondary end at least partially being displaced by the track system, thus pinching the track between the overhang on opposing ends of the plug.

Abstract: A device including an annular undercut having a curved cross-sectional shape made by electrical discharge machining (EDM) is disclosed. An exemplary device with an EDM-formed annular undercut is a tool used for injection-molding of plastic parts having a crab's claw seal.

Abstract: A method is provided for electrical discharge machining (EDM) a workpiece to include an annular undercut having a curved cross-sectional shape. The annular undercut is useful, for example, in making devices such as the tooling for plastic injection-molding of plastic parts including crab's claw seals. According to embodiments of the method, a workpiece is rotated about a central workpiece axis. An energized EDM electrode is moved in a plane containing the central axis and about an electrode axis generally perpendicular to the plane toward the rotating workpiece to provide a spark gap between the shaped electrode tip and the body. At least portions of the undercut are then formed by the EDM electrode as the workpiece is rotated. Devices made according to the forming methods are described.

Abstract: The invention is directed to an improved wear-resistant sprue bushing typically for use in plastic injection molding operations. The sprue bushing has a body member, a nozzle seat and a wear-resistant liner. The sprue bushing shortens cycle times by facilitating cooling and has an increased service life.

Abstract: The combination of a mold body for molded plastics or the like with a materials alloy core pin which at one and the same time establishes an aperture in the molded material and substantially reduces the mold cooling time by being formed from an alloy which rapidly dissipates heat that includes copper, nickel, silicon and chromium. The percentages of each material in the alloy can vary in a range but there is a preferred percentage to total materials for rapid cooling purposes.

Abstract: A quick set sprue bushing for use in combination with injection molding apparatus. The bushing is made from a beryllium-free alloy that will rapidly dissipate heat. The alloy is of the copper, nickel type and reduces the cure time by between 15% and 20%. The significance of being beryllium-free is that it has been established that beryllium is a carcinogen and endangers workers. A bushing of this type results in the sprue or tail of the molten plastic type cooling as rapidly as possible for removal of the molded product from the mold. The bushing is elongated and has a generally conical passageway along its longitudinal centerline axis that diverges in the direction of the flow of material therethrough, and is further provided with a stainless steel bushing insert at the end that receives the injection mold apparatus nozzle such that the bushing will not conduct heat from the injection apparatus to the mold but will dissipate heat from the mold that comes from the molten material.