Patent ID: 8419491

Claim:
A method for manufacturing a spark plug which includes a center electrode, a metallic shell having a bore extending in a direction of an axis, and a ground electrode disposed at a front end of the metallic shell and formed from a ground electrode member, wherein a step of forming the ground electrode comprises the steps of: cutting off a distal end portion of the ground electrode member which is provided on the metallic shell through shearing action caused by use of a movable blade, whereby a cut surface is formed at the distal end of the ground electrode member; and disposing at least one support part in a vicinity of the cut surface such that said support part prevents the distal end of the ground electrode member from moving in a direction in which the movable blade is pulled back after the cutting the distal end portion, wherein movement of the distal end would be caused by friction generated between the movable blade and the cut surface but for the support part.