To make improvements in finishing accuracy by installing a honing head, capable of imparting a contact pressure to a shaft hole inner surface to plural pieces of square bar fine grain honing sticks, in the spindle of numerically-controlled vertical lathe for wheel working, controlling both peripheral and vertical traveling speeds of the honing head, and finishing the shaft hole at a specified cross hatch angle.

In the case where a shaft hole of a wheel 17 is honed, an L-shaped groove 9 of a float joint 8 of a honing heat in accord with this shaft hole is fitted in a pin 7 of an outer cylinder 6 fitted in a mounting part shank of a unit spindle. Next, a fine grain honing stick 15 is inserted into the shaft hole, and then an expansion cylinder is expanded to some extent, extruding each sliding arm 11 by a cone part of connecting rod 13, and each fine honing stick 15 is widened to the specified size, pressing it to the shaft hole. Next, cutting oil is sprayed under rotating the spindle and, after the honing stick 15 is made to go down, a rising motion is repeated, whereby honing for the shaft hole is carried out. At this time, both rotating and lifting speeds of the spindle are controlled so as to make a cross hatch angle in a reference pattern come to 65 to 95°.