PURPOSE: To prevent a cutting chip from generating in a saw tooth and its quality from changing so as to set a shape of the tooth to be more accurately regulated, by using upper and bottom blades, which are formed in alignment with the original or the basic shape of the tooth to be set, so as to cut off the saw tooth.

CONSTITUTION: An upper blade 4 and a bottom blade 5 are prepared in alignment with an angle in the part of a tooth crest point 2 and a bottom land 3 in the original or the basic shape 1 of a tooth to be set. The upper blade 4, performing vertical motion in the direction of an arrow head A through struts 7, sets the tooth to be regulated cooperatively with the bottom blade for a part of the tooth whose setting is required. Prior to the above, the part of the tooth to be set is aligned positioning between the upper blade 4 and the bottom blade 5, and pressurization in the downward direction is applied to the upper blade 4.