Abstract: When machining small diameter holes, tool breakage and torque fluctuation at the machining point are detected. The machining method includes: measuring a reference thrust of a spindle when the spindle is fed from a machining feed start point to a machining end point in a direction in which the spindle extends under a machining condition without machining a workpiece; determining a threshold with respect to a feed coordinate based on the reference thrust; measuring a machining thrust of the spindle with respect to the feed coordinate while machining the workpiece; and comparing the machining thrust with the threshold with respect to the feed coordinate.

Abstract: When machining small diameter holes, tool breakage and torque fluctuation at the machining point are detected. The machining method includes: measuring a reference thrust of a spindle when the spindle is fed from a machining feed start point to a machining end point in a direction in which the spindle extends under a machining condition without machining a workpiece; determining a threshold with respect to a feed coordinate based on the reference thrust; measuring a machining thrust of the spindle with respect to the feed coordinate while machining the workpiece; and comparing the machining thrust with the threshold with respect to the feed coordinate.