old woman's tooth

An old woman's tooth is a hand-operated router with a small, narrow cutting head, traditionally used in carpentry to cut grooves, rebates, and decorative edges along the length of timber. Unlike a plane, which removes a continuous shaving, the router's cutter rotates to gouge out material in a controlled path, typically working along the grain rather than across it. The tool gets its peculiar name from the resemblance of its cutting head to a worn, prominent tooth.

The body of the tool is usually wooden, with a sole that slides along the workpiece and guides the depth of cut. A single handle or knob allows the user to push and steer the router in a straight line, while the rotating cutter does the actual work. The cutting edge itself is a small, hardened steel bit, often rectangular in profile, mounted in a spindle that turns either by hand crank or through a shaft driven by a treadle or foot pedal on larger workshop versions. Most hand models require constant manual rotation of the spindle.

This tool was essential before electric routers became commonplace. Carpenters used it to cut window muntins, door frame grooves, and the channels in traditional furniture construction. A skilled operator could work accurately to within a sixteenth of an inch, though the work was labour-intensive and required steady pressure and control. The slow, deliberate cutting action made it possible to work hardwoods and veneered panels without tearout, because the speed and feed were entirely within the operator's control.

Common failures occurred when the user applied inconsistent pressure or allowed the tool to drift sideways, resulting in a grooved path that wandered in depth or width. The rotating bit could also grab the wood suddenly if the grain reversed or if the operator fed the tool too aggressively. Because the cutting head was exposed, hand and finger injuries were a real hazard, especially when the tool broke free from the work.

Today the old woman's tooth survives mainly in restoration work, heritage carpentry, and among hand-tool enthusiasts. Modern electric routers have largely replaced it, offering faster speeds and more consistent results with less physical effort. However, its simplicity, quietness, and the direct tactile feedback it provides still appeal to craftspeople working on historical pieces or in situations where electricity is unavailable. Used examples remain available through antique tool dealers and are relatively affordable.