How to Mortise a Door
When you install a new door, sometime you start with a door blank. A door blank is a door without door knob holes or hinge cut-outs. Installing door hinges require cutting a mortise in the door to allow the hinge to sit flush on the door surface. Most people do not have a router available to cut a mortise. You can cut a mortise in a door with simple hand tools. It is important however, that the blades of knifes and chisels be sharp for accurate cutting. Does this Spark an idea?
Other People Are Reading
Things You'll Need
- Tape measure
- Pencil
- Combination square
- Utility knife
- Awl
- Wood chisel with 1-1/4-inch blade
- Hammer
- Medium grit sandpaper
Instructions
-
Marking for the Mortise
-
1
Measure where you want the center of the hinge on the edge of the door with a tape measure. Adjust a combination square to the 1/4-inch mark. Place the square on the edge of your door near your center mark and draw a line on the door edge. This line serves as a level for making the rest of the marks necessary to mortise the door.
-
2
Place the hinge on the door edge with the edge of the hinge even across the 1/4-inch mark and the center of the hinge at your center mark. Score the door along each side of the hinge with a sharp utility knife. You can use the line you made with the combination square or score the line on the wood for the end of the hinge with an awl.
-
-
3
Lift the hinge off the door edge and place the end edge of the hinge on the face of the door below the outline. Mark the hinge thickness with a pencil. This serves as a depth gauge for you when you are chiseling the mortise.
Mortising the Door
-
4
Position the blade of a 1-1/4-inch wood chisel at a 45-degree angle over the outline starting at one of the utility knife score marks. Tap the end of the chisel with a hammer until the blade reaches the depth mark.
-
5
Lift the chisel out and reposition it 1/8-inch in front of the first cut. Tap the handle with a hammer to the depth line. Continue repositioning and chiseling in 1/8-inch increments through the entire outline.
-
6
Hold the blade with the flat side even with your depth mark. Tap the chisel handle and remove the wood from the outline.
-
7
Continue removing the wood from the outline until all pieces are gone. Sand the mortise lightly with a medium grit sandpaper to even the mortise surface.
-
1
Tips & Warnings
You can mortise the edge for a door knob in the same manner. To achieve the proper depth, mark the flat side of the chisel blade to the thickness of the latch plate. Dig the chisel into the door until the line on the chisel meets the door surface.
