Mortise locks are locking latch
mechanisms which require a rectangular hole in the door edge for
installation. By fitting a mortise lock on your door, it is very
difficult to force open as it is fitted into the thickness of the door.
It is cut into the edge of the door and only the faceplate of the lock
is visible when the door is opened. In other words, a mortise lock is
one that requires a pocket - the mortise - to be cut into the door into
which the lock is to be fitted.
Parts Included in the Mortise Lock
The parts included in the typical mortise lock installation are:
- Lock body: This is the part installed inside the mortise
cut-out in the door.
- Lock trim: This may be selected from any number of
designs of doorknobs, levers, handle sets and pulls
- A Strike Plate or a Box Keep: This lines the hole in the
frame into which the bolt fits and
- Keyed Mortise Cylinder: This operates the
locking/unlocking function of the lock body. However, there are
certain mortise locks that do not use cylinders, but have lever
tumbler mechanisms.
Feature of Mortise Locks
- This lock consists of a flat, rectangular box that fits into a
recess in the door from its edge.
- It also includes two face plates that include the knobs and
keyholes.
- The locks are available in right- or left-handed styles.
- It also has a pin tumbler locking mechanism in a cylinder.
- The lock operates from either side except when the outside knob
is locked.
- Deadbolt operates by a turning the inside knob.
- A key from the outside operates both the latchbolt and deadbolt.
- The lock can be used on many types of doors, from heavy entrance
doors to apartment buildings and residential doors.
Materials Used
- Brass
- Aluminum
- Bronze
- Steel
- Iron
Types of Mortise Lock
- Full mortise locks: These fit completely inside the door
in a mortise pocket.
- Half mortise locks: These locks fit on the inside of the
door in a mortise notch and the back of the lock is exposed.
- Non mortise locks: These are surface mounted to the
door.
Sizes of Mortise Locks
Mortise locks are available in various sizes. However, the common size
is 100 mm (4 inches) deep. There is also a narrower version available
for a narrow stile, where the lock body measures 65 mm (2.5 inches).
Designs of Mortise Lock
Although the installation of a mortise lock actually weakens the
structure of the typical timber door, a mortise lock is more useful than
a bored cylindrical lock, both in external trim, and functionality.
Whereas the latter mechanism lacks the architecture required for ornate
and solid-cast knobs and levers, the mortise lock is available with a
heavier return spring and a more solid internal mechanism, making their
use possible.
