The polygonal profile is machined by the lathe tool which is reciprocated lateially and synchronized with the revolution of the main spindle.
To study peculiarities of such an unordinary lathe turning, three components of cutting forces were measured by the wire resistance dynamometer in these experiments.
We can understand that the cutting forces are under the cyclic variation with the lateral movement of cutting tool, but only a little time-lag is observed between the cutting force curve and variation of rake angle.
As the results of comparison between the turning of circular and polygonal shaft of the same condition, we can make out that the radial force is influenced extremely by the polygonal turning, and the axial force is in the second place and the tangential force is affected a little.