Abstract: A method and apparatus for forming attachment pads on a panel for attachment of a clinch nut thereto. The panel is formed between a forming die and a fixed anvil, which occupies a predefined net reference position. A face plate simultaneously “finds” the panel and is mechanically locked into position using a novel force applying device. The face plate maintains the location of the surface metal around the forming die, thereby forming a raised pad at the predefined net reference position. The novel force applying device includes self-contained piston modules positioned in tandem. Each module includes a housing having a void and a piston mounted within the void. The piston includes a driven and drive surfaces, wherein fluid pressure acts against the driven surface to drive the piston in an advanced direction such that the drive surface of the piston abuts another piston for cumulative effect.

Abstract: A method and apparatus for forming attachment pads on a panel for attachment of a clinch nut thereto. The panel is formed between a forming die and a fixed anvil, which occupies a predefined net reference position. A face plate simultaneously “finds” the panel and is mechanically locked into position using a novel force applying device. The face plate maintains the location of the surface metal around the forming die, thereby forming a raised pad at the predefined net reference position. The novel force applying device includes self-contained piston modules positioned in tandem. Each module includes a housing having a void and a piston mounted within the void. The piston includes a driven and drive surfaces, wherein fluid pressure acts against the driven surface to drive the piston in an advanced direction such that the drive surface of the piston abuts another piston for cumulative effect.