Development and evaluation of a fine finishing end mill with high rigidity. The effect of a helix angle on the cutting force.

Abstract

The mechanics of oblique cutting indicate that the magnitude of radial force orthogonal to the machined surface can be reduced by increasing the angle of inclination. This paper deals with the experimental research to clarify the relation between the helix angle and the cutting performance of a helical end mill. The performance of an one-fluted end mill with various helix angles is verified through the measurement of cutting force, ploughing force and the surface profile error in the micro milling. It is shown that the radial force is dramatically reduced by increasing the helix angle, restricted within the cutting condition where the single tooth is engaged in the cutting operation. Also, it is made clear that the optimum helix angle which can reduce the surface profile error to the minimum value can be simulated from the measured relation between the radial force and the helix angle, even if the number of flutes engaged in the operation is shifted in each applied condition.