Rout ends and edges accurately with this rail-guided jig.
By Craig Bentzley
Overall dimensions: 18"w × 53⁄4"d × 10"h
Some woodworkers discount loose tenons as the poor machine-cut cousin of traditional mortise-and-tenon joinery, but I’ve found the joint useful in many instances. Joining parts using a pair of matching mortises and a snug-fitting wood strip, instead of sawing a tenon to fit a mortise, saves stock. And with the proper setup, loose tenon joinery is just as strong as its competition, but quicker and easier to accomplish. Wanting a slot mortiser but not willing to spend money for a commercial model, I used leftover material and spare hardware to create a simple rail-guided mortising jig for my plunge router. Despite my initial success, I further improved the jig by adding Bessey’s autoadjust toggle clamps. Now my revised jig is just as reliable and accurate as its predecessor, but thanks to the new toggles, slippage is a thing of the past. Once set, the auto-adjust hold-downs provide the same amount of pressure on a 21⁄2"- thick leg as on a 3⁄4" rail without needing to adjust the footpad. The jig can hold stock up to 8" wide and 33⁄4" thick. By adjusting the base dimensions, you can easily mortise still larger parts.