1 Assembling the jig
The multipurpose edge guide shown at right will allow you to cut either 45° miter cuts or 90° crosscuts with a saber saw or a circular saw. Make the jig from a piece of %-inch plywood, referring to the illustration for suggested dimensions. Cut the base in the shape of a triangle with one 90° angle and two 45° angles. (To make a jig for 30° or 60° miter cuts, the sides should be 12, 16, and 20 inches or a variation of the 3-4-5 ratio.) Screw the fences to the base—one on each side— opposite one of the 45° angles. The fences must be flush with the edge of the jig base.
Making a miter cut
To cut a miter using the jig, set the stock on a work surface with the cutting line on the board extending off the table. Align the cutting edge with the line and butt the angled side of the jig against the saw’s base plate, with the fence on the bottom of the guide flush against the edge of the workpiece. Clamp the jig in place and make the cut, keeping the saw flush against the jig throughout the operation (left). To make a 90° crosscut, use the square side of the jig as your guide.