Investigation of Machining Different Nominal Thread Diameters with the Same Thread Mill Tool Due to Varying Revolution Radius of Helical Interpolation Motion

In this study, we focused on screw cutting with a thread mill tool based on helical interpolation motion and proposed a novel monitoring method to achieve a high accuracy of screw cutting with a wireless holder system. In this paper, the machining of screws with the same pitch and different nominal diameters using the same tool was investigated. In addition, the method of drilling a pre-hole and then thread cutting, and the method of drilling a pre-hole and then thread cutting at the same time were studied. As a result, it was found that when machining threads with the same pitch and different nominal diameters using the same thread mill, the cutting force during machining is almost the same by considering the feed rate of the table to be constant at the cutting point. In addition, it was found that the radius compensation was likely to be the same if the feed rate was kept constant at the cutting point during threading after pre-drilling. On the other hand, it is necessary to consider the amount of radius compensation for each nominal diameter when both pre-drilling and threading are performed at the same time.