PURPOSE: To stably manufacture a cage type rotor of a motor having a low vibration and low noise by preventing a positional deviation of a weight to be fixed in the rotor of the motor in which an unbalance correcting weight is mounted.

CONSTITUTION: When a protrusion 8 is provided at an end face of a caulking jig 6 and a recess 7 is provided at an end face of a caulking pin 3 for fixing a weight 5, by pressing the pin 3 by the jig 6, to be crushed and deformed, the protrusion 8 of the jig 6 is introduced into the recess 7 of the pin 3, and the weight 5 can be fixed without deviating centers of the jig 6 and the pin 3. According to this method, the weight 5 is fixed at a normal position, the deviation of a center of gravity is eliminated, a moment expected for the weight 5 is assured, and a cage type rotor for a motor having a low vibration and low noise can be stably manufactured.