dog ring with dogs having rounded intersection edges between the flanks of the front and rear portions and having a maximum overlap length of the back taper area specific embodiments of the present invention have been described various alterations and modifications will occur to those skilled in the art in particular it should be noted that the calibration method described herein may also be used to form internal teethings of a ring in the case of an internal teething call major diameter the diameter defined by the base surfaces of the dogs and minor diameter the diameter defined by the upper surfaces of the dogs minor diameter lt major diameter thus for an internal teething the condition of a clearance between the preform and the dies concerns minor diameters a functional clearance is then preferably provided between the minor diameter of the preform and the minor diameter of dies 62 and 64 as a result the minor diameter of the formed teething is smaller than the minor diameter of the preform it should further be noted that the method described herein applies to dogs which generally but not necessarily have an involute shape it may also be applied to dogs with planar surfaces the method also applies to the case where the characteristic angles of the front and rear surfaces are not constant warped profiles further the method discussed herein applies to the forming of any mechanical part comprising an element having dogs formed thereon further the method discussed herein.