Use locks of good quality or none at all. Never put very cheap locks on good work. There are many varieties of locks, some to be screwed on the outside of the wood, others to be sunk in recesses cut in the side of the wood, others still to be let into mortises - chest-locks, door-locks, cupboard-locks, drawer-locks, etc.

To fit a chest- or box-lock (not a mortise-lock), place the lock in the right position, mark around the part required to be sunk in the wood, which can be cut away with gouge and chisel, the keyhole having been bored quite through the wood and trimmed to a neat outline which will conform to the shape of the key. When the lock has been screwed in its recess, put the " hasp," or part which is to be on the lid, into its place in the lock, just where it will be when the chest is locked. Then close the lid, and by slightly pressing you can make a mark on it to show where to put the hasp. Sometimes you can mark the place with a pencil, or by putting transfer-paper between the hasp and the wood, or by rubbing blackened grease on the plate of the hasp. The plate of the hasp should be sunk in the lid to be flush with the surface, and may then be screwed on, bearing in mind the thickness of the lid when selecting the screws. A mortise-lock is fitted in a similar way, but let into a mortise (see Mortising).

To fit a common drawer-lock, determine the place for the keyhole and place the lock in position on the inside as before. With a pencil mark the outline of the box-part of the lock, which bears against the wood. Cut away the wood within this line, making a recess slightly deeper than the thickness of the box-part of the lock. The hole must be bored for the key, as before. Put the lock into place and mark the outline of the outer plate, not merely on the inside of the drawer front but also on the top edge. Cut away the wood with the chisel to let the plate sink flush with the wood. When the keyhole is shaped, try the lock and if it works, screw it on. Close the drawer and turn the key hard to raise the bolts (the tops of which have been previously rubbed with blackened grease, such as can be scraped from an oilstone, or using transfer paper), which, pressing against the wood, will mark the places for the mortises into which they are to slide. Cut these mortises and the drawer can be locked.

The variety of locks and their arrangement in regard to fitting is so great that it will be best for you to examine a well-fitted lock for the same purpose that the lock you have to fit is intended, for one rule cannot be given for all cases.