AS I WAS making a corner cabinet out of birch plywood with cherry facings and five-sided shelves, I encountered a problem. My design called for gluing cherry facing strips to the front edges, which I would then shape. However, the long front edge of the shelf had no opposing parallel edge to use for clamping. I developed this jig so I could clamp the facings to the front edge of the plywood.
I made the three-part jig (tongue and two cheeks) from scrap plywood. The tongue is about 7" long and 1½" to 1¾" wide and should be made from the same thickness of plywood as the workpiece to which you will be clamping the facing. Cut the tongue to give a 45° end. The final length should be about twice as long as that of the cheeks, so that a bar clamp and a C-clamp do not interfere with each other. Make the two cheek pieces from scrap the same width as the tongue and about twice as long as the width (3-3½"). Screw and/or glue the cheeks to the tongue with a mitered edge facing away (sort of like a miter saw gone awry) to form a cradle.
To use the jigs, slide one onto the workpiece and move it up or down the long edge until the mitered edge is directly opposite the desired clamp point. Use a C-clamp to clamp the cradle tightly to the workpiece. A long bar clamp will then span the two parallel clamping surfaces. I used one of the jigs near the back corner and positioned two down the length, giving three points for clamping.
—Willard Anderson, Chapel Hill, N.C.