There are times when you need the fence and the miter-gauge slot on a router table or a shaper to be perfectly parallel with each other, such as when you are coping the end grain of rails in paneled-door construction. This jig lets you make small, incremental adjustments to the fence while ensuring that the fence remains parallel to the miter-gauge slot.
Start with a squared-up board about 4-1/2 in. wide and 20 in. long. Cut the board lengthwise at about 6¡. Attach one side of the board to a 2-in.-wide strip of 3/4-in. plywood that has been pushed into the miter-gauge slot in a vertical position. Now remove a semicircular area where the jig lines up with the cutter. Draw marks 1/2 in. apart on one side of the taper and draw a reference mark on the other. A movement of 1/2 in. left or right should translate to just under 1/16 in. in movement forward or backward in the fence. With this jig and the reference marks, it is easy to set the fence to make progressively finer cuts.
Bjarn Sorensen, Tempe, Ariz.
Fine Woodworking Magazine, October 2000 No. 144