Patent ID: 8122584

Claim:
A method of producing a honeycomb structure molding die for the use of molding a honeycomb structure body, the die having a plurality of feed holes through which molding material is fed and a plurality of slit grooves formed in approximating a lattice arrangement communicated with the corresponding feed holes, the method comprising steps of: preparing a metal material of a plate shape having a feed hole formation surface in which the feed holes are formed and a slit groove formation surface in which the slit grooved are formed; forming the feed holes with a depth in the feed hole formation surface toward the slit groove formation surface of the metal material without penetrating the metal material; forming the slit grooves of a straight-line shape or a line shape approximating a straight line in the slit groove formation surface of the metal material in approximating a lattice arrangement while moving a thin circular grindstone blade which is rotating in a straight-line direction or a line direction approximating a straight line and in reciprocating motion in order to cut the metal material with a depth of reaching the fed holes; and removing fine metal powder, generated by cutting the metal material, attached to the thin circular grindstone blade every time the slit groove is formed in the metal material, wherein; the step of removing the fine metal powder uses a dressing grindstone in which a plurality of polishing grooves are formed, and at least the outer peripheral edge part of the thin circular grindstone blade is passed through the polishing grooves every time the slit groove is formed, in the step of removing the fine metal powder from the thin circular grindstone blade, the dressing grindstone is placed at an upstream side of the metal material in the moving direction of the thin circular grindstone blade, and the dressing grindstone used during the step of removing the fine metal powder has a plurality of polishing grooves of a predetermined pitch, said predetermined pitch being equal to a pitch of the slit grooves to be formed in the metal material.