Abstract: A thread forming screw having a helical thread and a tapered lead-in section with a polygonal cross section is formed from a conventional blank by rolling the blank between a pair of thread rolling dies having means thereon to form alternating convex lobes and concave relief areas in the frusto-conical surface of the blank. Thus, the screw may be formed with a polygonally shaped threading end without a prior working of the blank's frusto-conical surface. Curved ramp surfaces smoothly interface the lobes and concavities to allow metal in a workpiece being threaded to roll into the concavities thereby reducing the torque needed to form a thread in the workpiece.

Abstract: A tilting terminal clamp including a threaded shank extending from a head end, an integral annular plate retaining ring spaced below the head and a plate having a frusto conical annulus about the shank aperture to provide a concave surface confronting the annular ring with the annulus being sized and shaped to substantially receive the annular ring.

Abstract: A thread forming screw having a helical thread and a tapered lead-in section with a polygonal cross section is formed from a conventional blank by rolling the blank between a pair of thread rolling dies having means thereon to form alternating convex lobes and concave relief areas in the frusto-conical surface of the blank. Thus, the screw may be formed with a polygonally shaped threading end without a prior working of the blank's frusto-conical surface. Curved ramp surfaces smoothly interface the lobes and concavities to allow metal in a workpiece being threaded to roll into the concavities thereby reducing the torque needed to form a thread in the workpiece.