This standard establishes the general dimensions of hand and machine dies for ISO metric triangular profile threads:
——coarse pitch, from M1 to M68;
——fine pitch, from MI X 0.2 to M56 The shape and dimensions of the entrance of the machine dies, the shape of the V-notch and the execution with or without a chamber having diameter D\ are left to the manufacturer's discretion. For the execution tolerances of the threaded part of the dies, see UNI...... (in preparation). For hand die holders, see UNI 7580.
UNI 7579-1976 history
1976UNI 7579-1976 Round manual and mechanical spinnerets. for triangular ISO metric threads