• In this video, This Old House general contractor Tom Silva shares his tricks of the trade for installing a mortised lockset.

    1. Hold the lockset's escutcheon plate on the door and mark the doorknob hole onto the vertical rail approximately 36 inches from the door bottom.
    2. Trace the lock mortise onto the door rail, and mark the hole for the doorknob.
    3. Use a combination square to mark the mortise outline onto the edge of the door. Mark a centerline down the edge of the door, too.
    4. Stand the door on edge and mount a portable drill press drill onto an electric drill.
    5. Make a jig from two 2x6s and two plywood blocks. Set the jig onto door edge and bore out the mortise with a spade bit. Vacuum out the wood chips from the mortise.
    6. Use a chisel to remove the excess waste from the holes and square up the mortise.
    7. Set the lock into the mortise, and trace around the lock plate with a utility knife.
    8. Chisel out around the mortise until the lock plate sits flush with the door edge.
    9. Clamp a scrap board to the backside of the door and drill the doorknob hole through door.
    • Difficulty: Moderate
      the work isn't all that difficult, but it does take patience, practice and a deft hand to produce a clean, snug-fitting lockset
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      Video Directory

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      Tools List

      • utility knife
        Utility knife, used to trace around lock mortise
      • combination square
        Combination square, for marking the mortise outline onto the door edge
      • chisel
        Hammer and chisel, used to form mortise after boring out the holes
      • drill
        Drill with portable drill press and assorted spade bits, used to bore out mortise
      • bar clamps
        Clamp, used to hold a scrap board to the door when drilling the doorknob hole
      • shop vacuum
        Vacuum, for cleaning wood chips out of mortise

      Shopping List

      1. Mortise lockset

      2. 2x6 and ½-plywood scrap, used to make a jig for supporting the portable drill press

      3. Scrap board, for clamping to door when drilling doorknob hole