Microcircular holes made in electrodeposited copper foil resulted in profound improvement in the copper electroplating method of stress analysis with respect to detection of the principal stress amplitudes in the machine parts under biaxial stress conditions. In this paper, with the goal of wide application of this idea, a practical method is presented which is applicable when the directions and locations of combined acting loads are unknown. The accuracy of this method is also ascertained by the combined load tests of cyclic torsion and plane bending to the plate element.