CMT Hinge Mortise Cut Router Bit, 3/8 in

The CMT 850.001.11 Solid Carbide Keyhole Bit is a precision-engineered industrial tool designed specifically for creating "keyhole" slots in wood. These T-shaped slots allow frames, plaques, and mirrors to be mounted flush against a wall by sliding over a screw or nail head. The bit operates in a three-step sequence: it bores an entry hole into the material, transitions to a narrow neck cut, and finishes by carving a wider internal chamber under the surface to accommodate the screw head. This feature is best suited for plunge routers, allowing for vertical entry and horizontal slotting movement. It can also be used in CNC machines or stationary router tables, provided the workpiece is securely clamped.