How to Fix Broken Door Jambs
- 1). Grasp the heads of any nails in the damaged area of the door jamb with pliers. Pull the nails out of the door jamb.
- 2). Measure the width of the door jamb. Cut two pieces of 1-by-4 pine to this length. Place one piece above the damaged area and one piece below the damaged area. Secure these pieces to the door jamb with nails.
- 3). Measure the distance between the two pine pieces. Cut another piece of 1-by-4 to this length. Place the piece on the door jamb, between the other pieces, to form a square around the damaged area. Secure this piece to the jamb with nails.
- 4). Secure a collar piece to a router. Place the face of the router onto the square around the damaged area, and push the bit forward until it hits the door jamb. Move the setting pole back just far enough to fit the piece of wood you are using to patch between the setting pole and the face of the router.
- 5). Remove the patch piece from the router, and push the bit forward to accommodate the thickness of the patch. Plug in the router. Place the router bit in the damaged area, and remove the entire squared-off area.
- 6). Remove the 1-by-4 pieces from the door jamb. Place a chisel against the edge of the damaged area. Tap the back of the chisel with a hammer to clean up the edges and to make them more straight.
- 7). Place the bottom edge of the piece you are patching with against the bottom edge of the damaged area. Mark the top of the damaged area onto the patch piece by pushing a utility knife into the patch on either side.
- 8). Remove the patch from the door jamb, and lay it on a flat surface. Line up a carpenter's square from one utility knife mark to the other. Use the utility knife to draw a line across the patch, following the edge of the carpenter's square.
- 9). Cut the patch to size with a saw. Place the patch back into the damaged area of the door jamb. If the patch is too wide, push one side of it against the edge of the damaged area. Place a carpenter's square on the other side where you need to cut the patch to fit. Cut along the carpenter's square with a utility knife.
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Place the patch into the damaged area to ensure a right fit. Remove the patch, and lay it face down on a flat surface. Spread wood glue along the back of the patch. Lift the patch, and push it into the damaged area. - 11
Hammer finishing nails through the patch and into the door frame to secure the patch in place. Sand the patch with 120-grit sandpaper. Spray or paint primer over the top of the patch. Stain or paint the patch a color to match the rest of your door jamb.
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