Abstract: A die for use in extruding helical gears includes a die orifice at the upper end of the die teeth where the extrusion blank first enters the die. Each tooth is formed with a land directed parallel to the helix on the drive and trail side of the tooth and an end face perpendicular to the helix that intersects either a transition surface, directed perpendicular to the die axis, or a land. Alternatively, the end face can extend entirely across the tooth width from one land to the other without the use of the transition surface. Relief surfaces slope inwardly from the land and provide spaces within which the extrusion blank may expand without undue frictional contact with the die.

Abstract: A sheet metal blank is placed at the entrance of a die having a splined interior contour. A punch having a conjugate splined surface enters and passes longitudinally through the die. The splines are formed by passing the blank and punch through the die within an annular space whose contour defines the final spline configuration. Alternatively, preformed splines having a large pressure angle and full corner radii are reformed by multiple passes through dies whose configurations vary to produce shallow pressure angle splines and tight corner radii.