Method of producing press-forming punch and die

A method of producing a press-forming punch, comprising the steps of:

• preparing a master die and a master punch relatively movable toward and away from each other so as to define therebetween a die cavity;
• relatively reciprocating the master die and the master punch together while a first blank sheet is disposed between the master die and the master punch, thereby press-forming the first blank sheet into a press-formed panel complementary in contour to the shape of the die cavity;
• while a second blank sheet is disposed between the master die and the master punch, relatively reciprocating the master die and the master punch together with a stroke smaller than the stroke achieved when the press-formed panel is produced, thereby producing a half-pressed panel;
• applying an elastic material onto one surface of the half-pressed panel which has been situated face to face with the master punch;
• fitting the press-formed panel over the master die and placing the half-pressed panel over the press-formed panel with the elastic material facing away from the press-formed panel;
• forcing the half-pressed panel against the press-formed panel via the elastic material to thereby shape the half-pressed panel into a punch panel complementary in contour to the shape of the press-formed panel;
• and
• applying a back-up material to the rear surface of the punch panel to thereby produce a press-forming punch.