The brace is a u shaped steel hand tool that has a wood cap on one end and a bit chuck on the other.
How to install a mortise lock in a new door.
Fit the halves of the lock barrel through the holes in the mechanism and install the two mounting screws inside the door.
To install a mortise lock into a wood or composite door requires a pocket drilled into the edge of the door with the centerline of the door prep at 39 3 16 above the finished floor.
Fit the latch and faceplate into the door.
The spindle or shaft of one doorknob fits through the lockset body into the doorknob on the other side.
Create the mortise using a router attachment remove the wood between the pencil lines drawn on the door edge to create a mortise for the faceplate.
Insert the doorknob and doorknob plate together on both sides of the door at the same time.
The correct positioning of the lock is crucial.
Easy to follow instructional video on how to install a mortice lock in a timber door.
To avoid any error you should mark the position where you want to install the lock on the door.
Use a bevel edge chisel and hammer to square the corners of the mortise if the faceplate has square corners.
In the early days the pocket was cut out using a brace and bit.
Usually the professionals measure up to 36 inches from the bottom where the lock they set.
Step 4 remove the striker plate from the door jamb.