PURPOSE: To prevent discrepancy of the axial center of shaft member and the center line of center hole by giving a tapered part which is upwards extended in the tip part of a die and forming inclination corresponding to the tapered part of the die pin on the guide surface of pin guide.

CONSTITUTION: The tapered part which is upwards extended is formed in the tip part of the die pin 4 and the pin guide 5 is provided with down-narrowed inclination corresponding to that tapered part. In the process of forming that a shaft member 1 which is loaded in the die is pressed with a punch 3, because the die pin is coincided with the inclined surface of the pin guide even if that punch is reached the bottom dead center, the die pin is not deviated in the range of clearance. Accordingly the axial center of the shaft member and the center line of the center hole are not offset. In this way, such work as adjusting the length of the die pin by trial and error can be omitted.