A method of calculation of cutting forces at diamond grinding of brittle materials is
proposed in article. The cutting forces: normal, tangential and fracture, acting to single grain are
calculated. Total grinding forces are defined by average number of grain in contact zone.
Calculating values of forces are compared with result of experimental approximation of measuring
force at grinding of glass-ceramic workpiece. Grinding forces increase with increasing of diamond
grains wear and can be indicative of grinding wheel blunting