We report a centerless grinding machine which can perform multi-function with 600 mm wide grinding wheels. By increasing manufacturing area, long workpiece such as camshaft and steering shaft, is allowed to grind more quickly, compared with cylindrical grinding system. In this paper, the design of centerless grinding machine puts emphasis on symmetry to exploit the thermal stability. Results of finite element analysis shows that the difference of the structural deflection in the front and rear guideways is less than 1.5 μm due to symmetric design. The difference is less than 3.0 μm, even though the thermal deformation is considered. According to the performance evaluation, the radial error motion of the G/W spindle, which is measured by applying Donaldson Ball Reversal, is about 1.1 μm. The yaw error of the G/W slide is improved from 2.1 arcsec to 0.5 arcsec by readjusting the slide preload and ball screw.
