1. Clamp a straightedge to a scrap of lumber. Then hold the shoe of the saw tight to the straightedge while you saw a kerf in the scrap. Measure and record the exact distance between the straightedge and the inside edge of the saw kerf.
How To Use a Circular Saw To Make Long Cuts Learn how to safely saw boards freehand, cut plywood with a straightedge guide and build a ripping jig for accurate cutting with a circular saw.