PURPOSE: To attain mass production with a deviation within azimuth setting accuracy in a jig, by inserting the pin of the jig to the hole of a core block joining body, turning the joining body, and slicing it setting an angle at an azimuth.

CONSTITUTION: Core block joining bodies 10 and 11 are the ones having azimuths of +θ° and the inverse of -θ°. And both side planes of the azimuth dividing piece 22 connecting slidably with each of the joining bodies 10 and 11, is formed in a taper shape having angles of +θ° and the inverse of -θ°. By fitting the guide pins 16 and 17 in the azimuth setting position aligning holes 18 and 19 of such joining bodies 10 and 11, turning them almost in a truncated chevron pattern centering the pins 16 and 17 respectively, and bringing into contact with the dividing piece 22, the joining bodies are fixed. In such a state, by slicing the joining bodies with a wire saw 23, core chips having the azimuth of +θ° and the inverse of -θ° respectively can be obtained. In this way, the azimuth of a magnetic head, or the dimension accuracy of a magnetic gap height can be decided as a design accuracy of a stool jig, thereby the mass productivity being improved.