Abstract: A method of producing bimetal electrodes in which a core of copper is enclosed within an outer covering of a nickel alloy. The alloy is extruded into a relatively small diameter, deep cup by first forming a cylindrical blank with a rounded indentation in one face and thereafter extruding the cup using a punch having an end conforming with said indentation to form a central opening having a diameter at least three times the diameter of the punch. A cylindrical copper core is then firmly seated within the cup, which is then extruded by two stages to form an elongated, cylindrical blank. In one embodiment, the end is finished by trimming away a flaring skirt portion at the open end and thereafter upsetting the blank. In another embodiment, the flared skirt portion of the nickel alloy is bottled inwardly and pressed flat against the exposed end of the core so that no scrap is produced.

Abstract: A method of producing bimetal electrodes is disclosed in which a core of one metal is positioned within a cup of another metal so that the core is recessed back from the open end of the cup. In two embodiments, where the core is fully encapsulated, the open end of the cup is initially bottled or bent inward and subsequently the assembly is pressed through an extrusion die with a tool having a nose with an area substantially equal to the area of the core. In one such embodiment, a weld lug is produced by said tool during the extrusion. Such tool completes the closing of the open end of the cup to fully encapsulate the core and applies the principal extrusion force through the closed end to the core and from the core to the forward end or originally closed end of the cup. Subsequently, the extruded part is trimmed and additionally worked as required. In another embodiment, similar tooling is provided to produce an electrode in which the core is not fully encapsulated.

Abstract: A trim die system for trimming bolt heads or the like is disclosed in which a trim die is formed with a polygonal opening extending therethrough and providing cutting edges at the forward end thereof. The cutting edges are formed in the shallow recess in the forward end of the die, and are spaced back from a land which engages the tool to prevent contact between the cutting edges and the tool when operating without blanks. The land protects the cutting edges against damage and the structure provides increased die life. The tool is mounted for limited sliding movement and is biased toward an extended position. When the die first engages a blank supported by the tool, the tool moves back against the biasing force to reduce the initial impact on the cutting edges of the tool.