Polishing mechanism for metal casting base machining

The utility model relates to the technical field of grinding machines, in particular to a grinding mechanism for machining a metal casting base, which comprises a box body, a mounting plate, a first electric push rod, a cross-shaped sliding table and a stepping motor, the top of the box body is connected with the mounting plate in a sliding manner, and the first electric push rod is fixedly mounted on the bottom end surface of the mounting plate; and a cross-shaped sliding table is fixedly mounted at the bottom end of the first electric push rod. The water pump is started to pump out cooling water in the water tank and spray the cooling water to the polishing face of the metal casting base, generated waste water enters the water tank through the through opening and the through groove, the waste water is filtered through the filter screen box and can be recycled, the damage probability of the polishing face and parts and loss of the cooling water are effectively reduced, the polishing quality is guaranteed, an