Abstract: Wire stock for connecting rods is run through the nip of a pair of obliquely toothed rolls having teeth which taper from one face of the roll towards the other, and have a larger radius at the tip than along the portions flanking the tip. The angle of obliqueness matches the angle that a turn of a spiral wire will traverse the connecting rod. Round wire stock for the single-faceted spiral wires is run through the nip of a pair of rolls one of which has a cylindrical surface (i.e., a flat longitudinal profile), and the other of which has a circumferential groove with a slightly larger diameter than the round wire stock. As the wire is flattened on one side, its curved side is broadened. As the resultingly single-faceted round wire is wound into flattened spiral form, it is spatially orientationally guided, so that the facet becomes located facing outwards.