PURPOSE: To enable finish grinding of a bottom surface of the side edge of a gliding surface, the gliding surface and the side of the side edge by mounting a rotary tool having a sanding belt, a grinding wheel disc and a grinding disc for the side edge in such a manner as to be allowed to reciprocate in the longitudinal direction of a table.

CONSTITUTION: In the grinding work of work 7 as ski boards, firstly, the work 7 is supported securely on a table 2 by a plurality of support members 8 horizontally with the gliding surface thereof upward. Then, a boat-shaped base 4 and a frame 5 of the body 1 of the apparatus are adjusted to move horizontally and vertically so that the gliding surface of the work 7 matches a moving track of a grinding surface of a rotary tool 3. Then, the bottom surface of the side edge of the ski board 7 is ground by a sanding belt 20. Then, the tool 3 is operated to turn and a grinding wheel disc 21 is used to grind the gliding surface of the ski board 7. Subsequently, a finishing grinding of both sides of the side edge by a pair of grinding discs 22 for the side edge to complete the grinding work of the gliding surface.