Things You'll Need
Instructions
Mill one piece of marine plywood -- or any high quality plywood that will remain stable and unwarped, such as medium density fiberboard (MDF). Dimensions should be at least 1/2 inch thick to 3/4 inches thick, a minimum of 8 inches wide and 36 inches long, or longer. Mill a strip 8 inches wide using your table saw and rip fence.
Cut your strip of plywood 36 inches long using your chop saw or table saw, giving you a piece of plywood 3 feet long, 8 inches wide and 1/2-inch to 3/4-inches thick.
Cut a strip of hardwood 40 inches long by 2 inches wide and 2 inches high. Rip the hardwood on your table saw using your rip fence, then rotate it 90 degrees and make another rip, before cutting it to 40 inches in length with your chop saw.
Cut your 40-inch strip into two lengths, 37 inches and 3 inches.
Mark a pencil line on your piece of plywood 2 inches from the edge, running parallel, the length of the strip.
Determine the angle at which you want your jig to taper. You can use a bevel gauge, a straight edge or calculate the slope of the taper by the rise and run method -- determining how much taper you want for every linear foot and multiplying it by 3 feet.
Mark your taper line on the plywood. With your saw turned off, set your plywood in between your rip fence and the blade. Begin your taper line where your parallel line meets the edge of the plywood nearest you. It should veer toward the blade and away from your parallel mark along the length of the plywood.
Glue the back of your hardwood strip and lay it along your taper line. Firmly clamp each end of the hardwood runner to the plywood, then turn it over and reinforce the glue connection by predrilling and countersinking 1-inch drywall screws every 8 inches. The screws need to penetrate the wood runner. Their heads need to tighten into the countersunk pocket so they do not protrude at all.
Glue the 3-inch strip at the heel of the runner -- nearest you, perpendicular to your tapered runner, then screw them from the underside the same way you fastened the runner. Use two screws. The heel at the base of the runner should form an "L" with the foot of the L pointing toward the blade. It will hold the stock you're tapering as you run the jig through the table saw.
Cut two scraps of hardwood 1 inch wide by 1/2 inch thick and 2 inches long. Drill a hole 1/4 inch from the end of each of your 2 inch pieces, using a countersink. Screw them in at 1 foot intervals along your hardwood runner without glue. They should overhang the side of the jig facing the blade. These will act as tabs to keep your taper stock from rising as they pass through the table saw.
Test your jig. You should be able to set a piece of square stock, 2 inches by 2 inches, cradled in the "L" of your jig. Adjust your rip fence so blade will enter the wood at the top and exit the wood right at the toe of the "L" creating a finely milled taper.