Need to scribe a line down the center of a thin piece of stock? If it’s a typical thickness (1/4″, 5/16″, 3/8″, etc.), here’s a simple way. Lay the stock on a flat surface and use a brad-point bit with a diameter that matches the stock as a scribing gauge. Lay the bit next to the wood, and drag the bit’s tip along the edge or end to mark your scribe line. A quality bit will leave a perfectly centered line.
– Paul Guncheon