Estimation of cutting forces in micromilling through the determination of specific cutting pressures

In this paper a new model for the estimation of cutting forces in micromilling based on specific cutting pressure is presented. The proposed model includes three parameters which allow to control the entry of the cutter in the workpiece and which consider also the errors in the radial position of the cutting edges of the tool.Due to the difficulties presented in the manufacturing of the micromilling tools, manufacturing errors frequently appear. These are errors in the radial and angular position of the cutting edge and have significant influence in the estimation of the instantaneous cutting force in micromilling.The accuracy of the estimated parameters of the cutting force expression plays a major role in the resulting cutting force. For this reason, the influence of the fitting of the specific cutting pressure is analyzed.The new mechanistic force model determines the instantaneous cutting force coefficients using experimental data processed for one cutter revolution. The model has been validated through experimental tests over a wide range of cutting conditions. The results obtained show good agreement between the predicted and measured cutting forces.