To prevent the generation of neck cracks, etc., and to conduct centering of the neck chuck with high accuracy.

A centering jig 20 which functions as a dummy neck which is the reference of a neck 1c of CRT 1 is inserted in a cone receiver 11 on a cone receiving base 12, and the positional deviations of the centering jig 20 from a mounting head 13 in x-y directions are adjusted. After the adjustment, a neck chuck 14 is fitted to the position, which is determined as the reference position of the neck chuck 14.