Drawer-Lock Bit

The unique geometry of a drawer-lock bit creates a strong bond between perpendicular pieces. And the joint is not only functional, but attractive as well.

Unlike stub tenons made on a tablesaw, the wedge-shaped tenons created by a drawer-lock bit self-align both workpieces for a perfectly mating joint. Furthermore, once you've set the bit to the correct height, you need only adjust your router-table fence to make a variety of mating cuts.

One safety note before we get into using this bit: Remember that a drawer-lock bit should always be used in a router table, never a handheld router.

1) If your router table doesn't have a split fence, you'll need to build out the fence almost the full diameter of the bit. That's because most of the bit must be captured inside the fence when milling drawer or box sides.

Close up the opening around the bit by making an auxiliary face for your router table fence. For our 2"-diameter bit, we cut a ⁵⁄₈ x2-¹⁄₄ " dado in a scrap of ¹⁄₂ " medium-density fiberboard (MDF), then clamped it to the router table fence with the dado centered over the bit, as shown below.

2) Mount the drawer-lock bit in your table-mounted router, and set the top of the cutter so that it's ¹⁵⁄₃₂ " above the tabletop.

3) Calculate the fence position by adding your drawer front's intended overlap (if any) and the thickness of your drawer side. Position your router table fence that distance back from the upper cutting edge of the bit.

For example, if your drawer front will overlap the sides by ³⁄₈ ", and the sides are ¹⁄₂ "-thick, put the fence ⁷⁄₈ " back from the lower part of the bit. For flush-mount drawers, or drawers to which you'll add a false front, place the fence only the thickness of the drawer side from the bit's lower cutting edge.

(You also could use this dimension for milling the drawer backs. But here in the WOOD® magazine shop, we like to cut the backs with the same overlap as the fronts, then trim them to size. This ensures that the inside dimensions of the drawer remain constant.)

4) To prevent tearout while milling the fronts, attach a backer board to your miter gauge so that the backer board just touches the auxiliary fence face, as shown in drawing above.

5) With your drawer front already cut to finished size, place it faceup on the router table. Keep one end of the drawer front against the router table fence and mill the workpiece using the miter gauge as a guide. Turn the workpiece around, keeping it face-up, and mill the other end. If you're making more than one drawer, machine all of the drawer fronts (and backs, if you like) using this setup.

1) Without changing the cutting height of the bit, move the fence so that it's flush with the lower cutting surface of the drawer-lock bit. We like to rotate the bit so the cutting edge is forward, then lay a straightedge against it for reference, as shown below.

2) To prevent tear-out, make a pushblock from scrap and an extra piece of drawer-side stock (or scrap of the same thickness), as shown below. Make certain that the two pieces forms a 90° angle, and that the screws are high enough to clear the cutting path of the bit.

3) Cut the drawer sides to size. Stand the drawer side on end, placing the inside face against the fence. Use the pushblock, as shown below, to guide the drawer side through the bit.