Australian Wood Review – June 2017

http://www.woodreview.com.au 77

PROJECT

The main benefit of half mortise locks are the flush
surfaces that are left on all cabinet surfaces including the
interior. Although the shallow housings that are required
to fit these locks were designed initially with hand tools in
mind, the modern trim router now makes this job much
easier and more accurate.

The first crucial step to accurate fitting of these locks is
to be aware that the lock configuration can result in a key
that is off centre to the body of the lock (photo 1). For this
reason it is important to always start the layout from the
location of the keyhole rather than centring the lock body
on the inside of the chest.

With the position confirmed, use a marking knife to mark
out the housing that will take the main body of the lock
mechanism and set your trim router to cut a shade deeper
than the total depth of the lock (photo 2).

Square up the housing with a chisel and place the lock into
position to accurately mark the sides of the lock with a
marking knife (photo 3). Note there are two housings to
be cut next: one for the top edge of the lock, and one for
the brass backing plate covering the lock mechanism.

Mark the width of both the lock body and top edge with
a marking gauge (photo 4) and finally set the trim router

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1. Some lock configurations
   have a key that is off centre
   to the body of the lock.


2. Set your trim router to cut
   a shade deeper than the
   total depth of the lock.


3. Mark the sides of the
   lock carefully with a
   marking knife.
   4. Mark the width of
   both the lock body
   and top edge with a
   marking gauge.
   5. After routing, finish
   both housings with
   a hand chisel.
   6. Testing the final fit
   of the lock.

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