Influence of Pilot Hole and Work Material Hardness on Thread Milling with a Wireless Holder System

This study investigated the effects of simultaneously machining pilot holes and threads, as well as the accuracy of thread machining after pilot hole drilling. In addition, the thread machining of S50C and SKD61, which are work materials with different hardness, was also examined. Furthermore, a smart machining method for thread milling using helical interpolation was developed by monitoring cutting data using a wireless holder. The results show that the proposed monitoring method is effective for improving the accuracy of thread machining using helical interpolation motion of the threading tool. Moreover, this study discussed the differences in results due to the presence or absence of pilot holes. Finally, the influence of the hardness of the work material on the results was analyzed.