Accuracy test of a milling machine : rise in temperature of main spindle and accuracy of work

This is a report on the accuracy of machining which is changed by a rise in temperature of main spindle. The machine tool and cutters used in this experiment were a bed-type milling machine and end mills made of high speed steel respectively. The following conclusions were obtained. 1. In the case of high revolution number, the temperature of main spindle has risen remarkably for an hour. Since a dislocation of main spindle and a error of cutting surface increase with rise in temperature of it, a predrive is required. 2. The predrive had better be done in higher revolution number than used cutting condition. In this experiment, the revolution number of predrive is two times as many rotations as that of main spindle used, so that accuracy of work obtained by predrive only twenty minutes is sufficiently