Thread whirling process with a curved curve to suppress that can solve the problems caused by cutting or rolling, the moving path insert (13) to interfere both Desai, into time curve curve screws desired, it is an object of to provide such a method of manufacturing a screw with. A method of manufacturing a screw, in the case where the lead angle of the screw and mounting angle (β) is different, determined by the following formula mounting angle. Mounting angle = tan -1 {n × pitch / (π × D1)} D1 = {(the outer diameter of the screw diameter + of the Valley of the screw) / 2} + ΔT When the outer diameter ΔT> 0 of D1 ≦ ≦ screw diameter of the Valley of the screw, {(Screw outer diameter - the diameter of the valley of the screw) / 2} × 0.2 <ΔT <{(Screw outer diameter - the diameter of the valley of the screw) / 2} When <0 ΔT, - {(Screw outer diameter - the diameter of the valley of the screw) / 2} <ΔT <- {(- Diameter of the Valley of the screw screw outer diameter) / 2} × 0.2 However, 0, n D1 ≠ 0, ΔT ≠ is the number of threads転造や切削による問題を解決でき、インサート(13)の移動経路が所望のねじのカーブ曲線に出際・入り際ともに干渉することを抑制して、目的とするカーブ曲線を備えたスレッドワーリング加工によるねじの製造方法などを提供すること。ねじを製造する方法において、ねじのリード角と取り付け角(β)とが異なる場合に、取り付け角を下記式によって求める。取り付け角=tan-1{n×ピッチ/(π×D1)}D1 ={(ねじの谷の径+ねじの外径)/2}+ΔTねじの谷の径≦D1≦ねじの外径ΔT>0のとき、{(ねじ外径-ねじの谷の径)/2}×0.2<ΔT<{(ねじ外径-ねじの谷の径)/2}ΔT<0のとき、-{(ねじ外径-ねじの谷の径)/2}<ΔT<-{(ねじ外径-ねじの谷の径)/2}×0.2但し、D1≠0、ΔT≠0、nは条数
