Determine the spindle speed (RPM) and feed rate (IPM) for a turning operation, as well as the cut time for a given cut length. Turning operations remove material from a rotating workpiece by feeding a single-point cutting tool axially, along the side of the workpiece. Calculations use the desired cut diameter, cutting speed, and cutting feed, which should be chosen based on the specific cutting conditions, including the workpiece material and tool material. In some turning operations, the diameter of the workpiece will change so the spindle speed and cutting speed (SFM) must change as well. Typically, values are calculated for a single cut diameter and then either the spindle speed or cutting speed is held constant while the other varies.