Turning with suppressing thrust force has been proposed as a method of processing a micro-shaft. Advantages of thrust force free cutting have been demonstrated by turning micro-shaft (diameter: ~0.05 mm). Although the feed rate is a small value in the previous research, the processing efficiency has not been discussed because the processed shaft is small. If the long shaft is machined, it is indispensable to increase the feed rate to improve the machining efficiency. Therefore, in this research, we confirmed whether the suppression of thrust force was possible with high feed rate to expand the application range of thrust force suppression turning. The condition of suppressing thrust force by turning the long shaft of the medium diameter (~1 mm) was chosen, and the range of the small deformation by suppressing thrust force was clarified. It was also found that deflection due to principal cutting force also caused dimensional error even when thrust force was suppressed.
