Abstract
In NC-lathe operation, the spindle speed is programmed for the spindle revolutions per minute or the unit length per minute for the constant circumferential cutting speed. Additionally, the tool feed can be coded in terms of the unit length per minute or per revolution. This paper describes the derivation of formulas which enable calculation of tool movement time when the real tool feederate with velocity unit varies during linear and/or circular interpolation with the most widely used cutting conditions, that is, cutting speed in terms of the length unit per minute and feed in terms of length unit per spindle revolution.