Abstract: The apparatus includes a pair of spaced conveyors for conveying upper and lower frame plates through a pair of nailing assemblies. Each nailing assembly includes a nailing gun pivotal between upper and lower positions whereby nails can be driven through the plate and into a stud disposed between the plates at positions spaced along the width of the plate. The conveyor includes a drive unit for advancing the plates through the nailing assemblies discrete distances of 1.5, 16 or 24 inches. One of the conveyors and nailing assemblies is movable laterally relative to the other conveyor and nailing assembly whereby adjustments in width of the frame undergoing fabrication is accomplished. In use, a stud is butted against retractable stops upstanding between the nailing assemblies. Upon command, clamps carried by the nailing assemblies clamp the stud and frame plates one to the other and the nailing gun automatically drives a nail through the plate into the stud.