Patent ID: 7918118

Claim:
A method of using an electromagnetic forming machine to hem a plurality of panels to form a panel assembly, the method comprising: providing an inner panel having an outer edge; providing an outer panel having a central portion, a plurality of flanges disposed about a periphery of the central portion, and a plurality of relief areas, each relief area being disposed between adjacent flanges and each relief area having an upper surface; providing an electromagnetic forming machine having a coil for discharging electric energy to generate an electromagnetic force; positioning the inner panel adjacent the outer panel such that portions of the outer edge of the inner panel are aligned with the flanges of the outer panel and spaced apart therefrom to form a loose assembly of panels; positioning the loose assembly of panels proximate the electromagnetic forming machine such that the coil surrounds the plurality of flanges and is disposed generally below a plane formed by the upper surface of the plurality of the relief areas; wherein the coil is a single turn coil that has a varying cross section along a length of the single turn coil such that the single turn coil comprises a plurality of thick portions and a plurality of thin portions and wherein during the step of positioning the loose assembly of panels, the thin portions are aligned with the relief areas; and activating the electromagnetic forming machine to generate an electric current in the coil which induces an opposing electric current in each of the flanges whereby each of the flanges are bent over the outer edge of the inner panel to form a hem.