Abstract: A new and improved single tool or jig which is universally useable in connection with the fabrication or trimming of left and right side edge portions of stair tread components, left and right end portions of stair tread side edge plank components, and stair riser components, so as to permit all of such components to be properly mated together in order to impart to the exposed or open stair members a seamless finished appearance.

Abstract: A new and improved method for calibrating workpiece clamping mechanisms such that once a particular clamping mechanism is calibrated with respect to a particular workpiece to be clamped upon a support surface, the clamping mechanism will always clamp the workpiece with a predetermined, precisely repeatable clamping force. In addition, the method of the present invention may be utilized in conjunction with the calibration of a plurality of clamping mechanisms so as to enable the plurality of clamping mechanisms to always generate the same precise clamping force whereby the multiple clamping mechanisms, utilized to clamp a single workpiece upon a support surface, can in fact clamp different regions of the single workpiece with precisely the same predetermined clamping force such that all regions of the single workpiece are in fact securely clamped.