Abstract: A resistance welding electrode is formed of a hollow shank carrying current and cooling fluid and an electrode head connected to the shank by a flexible housing of insulated material. The housing forms a chamber to contain the cooling fluid supplied through the shank. The flexibility of the housing allows the head to rock relative to the shank and also to move axially away from the shank under the influence of the pressure of the cooling fluid. When welding pressure is applied through the electrode to a workpiece, the shank is forced against the head to provide firm electrical engagement between those elements.

Abstract: A clinch weld fastener and method of using the same to effect attachment of a non-ferrous panel, such as an aluminum panel, to a ferrous panel, such as a steel panel. The clinch weld fastener is in the form of a clinch nut blank, preferably of the self-piercing type, with weld projections extending from one end thereof. To effect assembly of the two panels together, the clinch weld fastener is first clinched to the aluminum panel with the weld projections extending outward from one surface thereof and then after placing the aluminum panel with the weld projections in abutment against the steel panel, projection welding the clinch weld fastener to the steel panel thereby securing the aluminum panel to the steel panel.