Abstract: A cutting tap includes a body having an axial forward end and an axial rearward end. The body has a threaded body portion with spiral flutes adjacent the axial forward end, a cylindrical shank portion adjacent the axial rearward end. The threaded body portion includes a chamfered fluted section and a constant diameter section. The threads have a chamfer relief extending radially inward from the cutting edge to a heel of a land. The amount of chamfer relief reaches a maximum value at a point between the cutting edge and the heel, and then becomes smaller between the point of maximum relief and the heel of the land to provide a clearance that reduces the propensity of the tap to chip.

Abstract: A cutting tap includes a body having an axial forward end and an axial rearward end. The body has a threaded body portion with spiral flutes adjacent the axial forward end, a cylindrical shank portion adjacent the axial rearward end. The threaded body portion includes a chamfered fluted section and a constant diameter section. The threads have a chamfer relief extending radially inward from the cutting edge to a heel of a land. The amount of chamfer relief reaches a maximum value at a point between the cutting edge and the heel, and then becomes smaller between the point of maximum relief and the heel of the land to provide a clearance that reduces the propensity of the tap to chip.