Fitting a Furniture Lock — Step-by-Step Guide

August 12, 2026

A furniture lock secures cabinet doors and drawers against unauthorised access, requiring precise drilling based on the cylinder diameter and backset measurement.

Retrofitting or replacing a lock on furniture made of chipboard, MDF, or solid wood is a precise task. An unevenly drilled hole or miscalculated measurement inevitably leads to a damaged furniture front. This guide is aimed at fitters and experienced DIY enthusiasts who wish to install a classic surface-mounted rim lock professionally. With good preparation, the actual installation takes around 20 to 30 minutes per lock.

Important Technical Parameters Before Installation

Before you begin drilling, two essential dimensions must be determined and understood. A standard furniture lock cylinder relies on specific dimensions to sit flush with the furniture front and carcass.

The Backset

The backset defines the distance from the front edge of the lock casing (the side from which the bolt extends) to the exact centre of the cylinder. Common measurements in cabinet making are 15 mm, 20 mm, 25 mm, or 30 mm. If you are replacing an old lock, the new one must have the exact same measurement, as the hole in the front is already present. For a new installation, this dimension determines how far from the door edge you must drill.

Cylinder Diameter and Cylinder Length

The cylinder diameter determines the size of the hole required in the furniture front. Typical values for a furniture lock cylinder are 18 mm or 19 mm. The cylinder length must match the material thickness of the door. On a standard furniture door with 16 mm or 19 mm thickness, the cylinder should project minimally or sit flush. A cylinder with a 22 mm length is ideal for a 19 mm thick front, as it leaves space for a potential rosette (escutcheon ring).

Required Tools and Materials

For a clean, breakout-free installation, you need the right tools. Improvisation on visible furniture fronts almost always leads to poor results.

A suitable furniture lock cylinder (including keys and any rosette)
Cordless drill/driver
Forstner bit or sharp lip and spur wood drill bit (matching the cylinder diameter exactly, e.g. 19 mm)
Small wood drill bit (2 mm or 3 mm) for pre-drilling screw holes
Try square (engineer's square)
Folding rule or precise tape measure
Bradawl or awl
Suitable wood screws (often 3.0 x 15 mm or 3.5 x 15 mm, depending on board thickness)
Screwdriver (usually PZ or TX)
A scrap piece of wood as a backing piece (sacrificial timber)
Clamps to secure the backing piece

Step-by-Step Guide: Installing a Furniture Lock

The following guide describes a new installation on a door without pre-drilled holes. Work with high precision at every stage.

Step 1: Determine and Mark the Position

First, decide at what height the lock should sit. For single doors, it is usually positioned centrally on the handle side; for drawers, exactly in the horizontal centre of the front. Measure the desired height and mark this point on the inside of the door. Place the try square against the door edge and draw a horizontal line inwards. Along this line, measure the backset (e.g. 25 mm from the edge) and mark the point using the bradawl. This small indentation prevents the drill bit from wandering.

Step 2: Drill the Cylinder Hole

This step determines the visual finish of the job. Drilling requires complete care on timber—once material is removed, it cannot be put back. To prevent tear-out on the coated front, clamp a piece of scrap wood (the backing piece) firmly to the outside of the door, positioned precisely over the drilling point. Place the centre point of the Forstner bit into the indented hole on the inside. Drill at moderate speed with light, steady pressure at an exact 90° angle through the door and into the sacrificial timber. The result is a completely clean, circular hole on the front face.

Step 3: Align and Screw the Lock Case

Insert the furniture lock cylinder from the inside through the newly drilled hole. Press the lock case flat against the inside of the door. Align the housing using the try square so it is perfectly parallel to the door edge. A crookedly mounted lock leads to latching issues later because the bolt extends at the wrong angle. Mark the fixing holes of the lock casing using the bradawl. Remove the lock and pre-drill the marked points with a 2 mm drill bit. Take strict care not to drill through the front. A depth stop or a piece of tape on the bit (e.g. at 10 mm depth) helps here. Reinsert the lock and secure it with the appropriate wood screws. Tighten the screws by hand to avoid stripping the thread in the chipboard.

Step 4: Position the Strike Plate

The strike plate (or striking plate angle) is the receiving fitting for the lock bolt. It is attached to the furniture carcass. Close the furniture door almost completely. Turn the key so that the bolt extends. Transfer the upper and lower edges of the bolt onto the inside of the carcass with a fine pencil. Now measure how far the bolt is set back from the door interior and transfer this measurement to the carcass. Position the strike plate against these markings. Mark the screw holes with an awl, pilot drill lightly, and screw the plate into place.

Step 5: Function Check and Fine Adjustment

Close the door and operate the furniture lock cylinder. The key must turn without noticeable resistance. The bolt must slide cleanly into the strike plate. If it catches, check where the bolt rubs. If it rubs at the top or bottom of the plate, loosen the strike plate screws slightly and shift it by a few millimetres. Many strike plates feature practical slotted holes for this purpose. If the bolt catches on the depth, the plate must be moved further forwards or backwards.

Common Installation Mistakes

Even experienced installers make mistakes when concentration slips. Avoid these typical pitfalls:

Measuring the wrong backset: If the distance is measured from the wrong edge of the lock (e.g. from the centre instead of the stop edge), the hole will be misplaced. The lock casing will either overhang the door edge or the bolt will fail to reach the strike plate.
Using screws that are too long: If the board thickness is 16 mm and you use 15 mm long screws plus a 2 mm lock plate, only 3 mm of material remains. If the screw is overtightened, the tip pushes through the front decor. Always select screw lengths to ensure at least 4 mm clearance to the front face.
Drilling without sacrificial wood: Pushing a Forstner bit through the front without counter-pressure will inevitably tear away the melamine coating or veneer in large splinters on the exit side, causing irreparable cosmetic damage.
Drilling at an angle: If you do not hold the drill at an exact right angle, the cylinder will sit skewed in the hole. The rosette will then fail to sit flat against the front on one side.

Maintenance and Care of the Mechanism

A mechanical component requires occasional care. Never use resin-forming oils or standard penetrating fluids in the cylinder. These attract dust and eventually gum up the delicate pins inside. Instead, use specialist graphite powder or a dry PTFE spray. A tiny application into the keyway every one to two years ensures the mechanism remains smooth and prevents the key from snapping.

FAQ – Frequently Asked Questions About Furniture Locks

Which drill bit is best suited for a cylinder lock? Always use a sharp Forstner bit or a specialist hinge boring bit. These tools have a distinct centre point and spurs that cleanly cut the edge of the hole before clearing material. A standard metal twist bit will tear the wood.

What does right-hand or left-hand handing mean for a lock? Many surface-mounted rim locks are non-handed (reversible for left or right use). However, some models are specifically handed for right-hand doors (hinged on the right) or left-hand doors (hinged on the left). Check which direction the bolt throws when the cylinder is correctly oriented before drilling.

Can I retrofit a lock to a drawer? Yes, the principle is identical. On drawers, the bolt generally throws upwards and locks into the rail above or the underside of the worktop. Ensure there is sufficient clearance above the drawer front for the extended bolt and the corresponding strike plate.

How do I remove an old, broken lock without a key? If the lock is open, simply unscrew it from the inside. If the door is locked and the key is lost, the cylinder must usually be drilled out. Place a 5 mm or 6 mm metal drill bit directly into the keyway and drill out the internal pins. The bolt can then usually be retracted using a flat-head screwdriver.