We recommend using MK2110 or MK2120 CNC internal grinder to grind the inner circle of gear. Selecting Which model depends on the grinding size of the work piece. The maximum internal grinding diameter of MK2110 is 100 mm, the maximum grinding depth is 150 mm, the maximum internal grinding diameter of MK2120 is 200 mm and the maximum grinding depth is 300 mm. Then the MK1620 NC end surface cylindrical grinder is used to grind the gear's outer circle and end surface. A customer asked that both ends have keyways, can they be automatically grinded? Of course, MK1620 external grinder is equipped with Accretech end-facing aligner to find the highest point, automatically skip the keyway grinding, we are equipped with radial gauge to measure the external diameter, and thickness gauge to ensure gear thickness. It is equipped with Siemens 828D NC system, THK ball screw, Rexroth guideway in Germany and NSK bearing in Japan. The measuring instruments are all from Accretech.