How to Mortise a Door Blank

Measure the door jamb with a tape measure on the hinge side. Note the distance from the top of the jamb and the top of each hinge. Measure the depth of the hinge placing, from front to back.

Transfer these measurements onto the door using a pencil. Place the hinge at these places and trace around them so you have a clear area to mortise.

Measure the door jamb on the knob side. Write down where you will need to mortise the door knob catch on the door blank. Transfer these measure measurements to the door blank as in Step 2.

Use a sharp utility knife to cut the outline of the door hinge mortise. Cut away the material inside the door hinge area to mortise out the hinge location. Complete this for all three hinges so n the door.

Place the hinge in your mortise area to ensure the hinge is flush with the door edge. Continue to remove material until the hinge is level with the door blank edge.

Flip the door over and trace the area for the door knob plate. Use the utility knife and chisel to mortise out the plate location. Stop when the plate is level with the door edge blank.