Improving finishing efficiency using a cover plate in gyro finishing

Gyro finishing -a type of mass finishing-is one of the potential processes for finishing complicated shapes. This study proposes a cover plate located above a workpiece to improve finishing efficiency in gyro finishing. First, the effect of the cover plate on the force acting on the workpiece, which is related to the finishing efficiency, was investigated, and we confirmed that the force increased by using the cover plate. This was considered to be caused by the restriction of upward motion of the abrasive media. Subsequently, the effect of the cover plate on the finishing efficiency was evaluated by comparing the surface roughness variation with and without the cover plate. The finishing efficiency of the workpiece surface increased by approximately a factor of 2.0 with the cover plate due to the large force acting on the workpiece. Additionally, the bad effect caused by using the cover plate via larger force acting on the workpiece-worsening of the surface roughness-was not revealed. Therefore, the cover plate was confirmed a highly effective method to improve its performance. Furthermore, the effect of the cover plate was investigated under the workpiece-stopped condition for an improved understanding. We confirmed that the surface roughness obtained using the cover plate improved over the entire front surface of the workpiece due to the increase of the contact pressure.