Spindle Rotational Speed Effect on Milling Process at Low Cutting Speed

The spindle rotational speed fluctuates during milling due to intermittent cutting forces applied to the spindle, but the speed effect when machining with a relatively large cutter at low cutting speeds is still not clear. The focus of this paper is to investigate the effect of spindle servomotor dynamic characteristics on milling processes at various rotational speeds. Based on the simulation and experimental studies, it was found that the cutting speed fluctuation is not negligible at low operation speeds and that the spindle servomotor dynamics affect the machining process and tool life. Thus, it was concluded that the spindle dynamics have to be carefully evaluated and chosen when testing machinability of metals, especially low rotational milling applications typically required for machining of difficult-to-cut materials.