PURPOSE: To improve the precision by setting a grinding wheel for grinding and shoes of a supporting means changeable for a grinder for shaping the grinding wheel for grinding receiving a shaping force for the grinding wheel for grinding by a grinding wheel for shaping by the shoes and detecting a fluctuation of the shaping force applied on the grind wheel for grinding by a sensor and load cells.

CONSTITUTION: A shaping means for grinding wheel T2 is set at a shaping position after a work drive means is retracted from it, and a grindwheel 18 for grinding of a grinding wheel means is set at the shaping position. A support means T3 is then moved toward the grinding wheel 18, shoes 30, 34 are positioned at a support position of the grinding wheel 18, and both shoes 30, 34 are put to get in contact with the grinding wheel 18 at a constant contact pressure. The grinding wheel 18 is then rotated at a set rotation number, a grinding wheel means for shaping T2 is driven to the grinding wheel 18 by a servo motor 14, and it performs shaping at a constant shaping force. The shaping force is detected by a pressure sensor S1 and load cells 32, 36 at this time, and the position of a grindwheel for shaping 27 and the shoes 30,34 are regulated to set the fluctuation of the formation force to the minimum by a shaping force control means C.