The Finest Brass and Iron Hardware Available for Furniture and Home.

Installing Full Mortise Locks

Full mortise lock installation

A full mortise lock is embedded into a deep mortise cut into the edge of the door or drawer. The exposed "selvedge" and a keyhole are all that is visible of this type of lock. Unless some unusual consideration comes into play these locks are generally centered in the thickness of the material.

Because the lock is normally placed in the middle of the material thickness the choice of escutcheon and the method of its attachment will be a consideration. Thread escutcheons rely on a viable thickness for secure mounting and surface mounted escutcheons need adequate material thickness for their fasteners. Even with modern full mortise locks whose bodies are barely 1/4" thick you are unlikely to find more than 1/4" of wood to work with.

The keyhole of this type of lock is not centered and the layout must be adjusted with this in mind. Beyond this consideration the mechanics of cutting the mortise are simple enough. Unless you are restricted to only hand tools you are likely to use a drill press to bore a series of holes that are then connected with a chisel or use a drill press mortising attachment to the same end. If you will be installing a full mortise lock on a door it might be worth cutting the mortise before the door is assembled, this is particularly worthwhile if the door is wide or of frame and panel construction. A wide door might not fit between the chuck and table of your drill press and a frame and panel door could flex under the pressure of the mortising drill.

The selvedge on these locks will always be bigger than the lock body so the precision of the mortise can be somewhat questionable without any real harm being done. With the primary mortise cut the lock can be dropped into place and the outline of the selvedge marked with a sharp knife. I use a router to cut the shallow mortise for the selvedge. After the appropriate keyhole is cut the lock can be installed.

Relevant Products
Full Mortise Locks