How to safely rout along a narrow edge

Here's a simple way to support your router when machining along the edge of a part, such as for rabbeting the edge of a cabinet to receive the back. Clamp a 1¹⁄₂ "-wide scrap (a 2x2 works great) of the needed length to the part, flush with the edge, as shown. The scrap provides sufficient bearing surface, so you can keep the router stable and make a straight cut.

—From the WOOD® magazine shop