Low-dough tablesaw safety guard
Clamp your safety guard and stop in place, as shown. Adjust the rip fence so that the distance from the stop to an outside tooth of your dado set equals the width of your workpiece. Set your miter gauge at 90°, and cut away the underside of each rail at each end. Make two or three passes, as necessary. For the final pass, butt the end of the rail against the stop.