Abstract: A method of fabricating a composite metal panel (10) is disclosed, with the panel being particularly adapted for use in constructing railroad passenger cars, and comprising a sheet metal outer component (11) resistance-welded to the lands (15) of an underlying corrugated metal component (12). The method includes laying the outer component (11) on a cooled copper bed, which forms one electrode, and placing the corrugated component (12) having a plurality of laterally spaced apart lands (15), on top of the other component. A welding apparatus electrode is applied to the rear surface of the corrugated component at spaced-apart locations (X), and current is passed between the two electrodes to thereby resistance-weld the lands of the corrugated component to the outer component at the spaced-apart locations. The copper bed is cooled by passing a cooling fluid therethrough.