This simple guide guarantees success whenever you need to make a straight routing pass. It’s perfect for jointing a long edge or routing dadoes and grooves. You’ll get smooth, chatter-free results, thanks to the guide’s firm support fence. Positioning the guide is foolproof, because it’s dedicated to the bit you plan to use.
The guide is nothing more than a 1/2-in.-thick fence glued to a 1/4-in.-thick base. The base protrudes by the radius of the router’s base. The fence must have a straight edge—I used the factory edge of my MDF. Routing the base with a straight bit completes the guide (see photos, below).
To use, simply align the guide’s base with your cutline on the workpiece. Clamp the guide in position and rout, using the same straight bit that you used to complete the guide. For best results, don’t try to remove more than 1/16 in. from the edge or to rout a dado deeper than 1/4 in. at a time.
The guide works perfectly with your router, because you use your router to make it. Make the base extra wide; then trim it with your router. Now when you use the guide, the routed base indicates the edge of the cut, as long as you rout with the same bit or another bit with the same diameter.
A short guide is perfect for routing dadoes and rabbets. Make sure the guide extends beyond the workpiece on both ends.
Difficult operations, such as squaring the ends of a large tabletop, are a breeze. When you rout end grain, clamp a block against the back edge, so you don’t blow it out.