The power consumption while machine runs idle (i.e. do not perform machining operation) is less than that when it performs machining operation. Hence, the actual power consumption was measure by subtraction of those two values of power consumption for the machining operation under observation. The results of surface roughness and power consumption are shown in the figure 4, figure 5 and figure 6. The effect of spindle speed, feed rate and depth of cut on surface roughness and power consumption are presented in figure 4, figure 5 and figure 6 respectively.