It is an object of the invention to prevent a lapping member from being cut by an edge of a slider when the edge is chamfered by lapping it with the lapping member. A slider held by a slider holding jig according to the invention is put in contact with a diamond lapping sheet. A load applying portion moves weights provided in the form of a plurality of stages downward from a state in which the lower end of a shaft portion of the weight at the bottom stage is located above the slider holding jig without contacting the slider holding jig, thereby loading the slider holding jig with the weights sequentially from the bottom stage.