This low-cost slot mortiser utilizes my Sears saw table and motor. The arbor platform sits snugly in a space between the saw table and a catching table I built behind the saw. Short rails under the platform fit the miter-gauge slots to keep the platform from shifting. The V-belt on the arbor twists 90¡ and slips over the saw’s motor pulley (the direction of twist determines which way the arbor will turn), and then the weight of the motor keeps the belt taut.

The sliding table consists of two plywood sleds that allow forward-and-back and side-to-side motion. Hardwood runners are attached to the lower sled, top and bottom. The top sled has two sets of grooves, so it can be repositioned atop the lower sled for end-grain mortising, at 90¡ from the position shown in the sketch. Various stop blocks limit the mortiser’s travel and control mortise depth. To adjust for mortising stock of various thicknesses, shim the work or the arbor platform.

Joel Katzowitz, Marietta, Ga.

Fine Woodworking Magazine, December 1984 No. 49