Adjusting Cam Connectors: Optimising Tightening Travel for Seamless Cabinet Joints

January 31, 2026

A cam connector pulls in the connecting bolt via an eccentric curved track inside the housing, creating a strong, right-angled, and seamless board joint.

The precision assembly of a cabinet carcass relies entirely on the quality of its corner joints. If a visible gap remains after joining chipboard or MDF panels, this is rarely due to the board cut itself. Instead, it is usually caused by insufficient or incorrectly adjusted tightening travel of the carcass connectors. A gap of just 1 mm quickly accumulates across multi-section wardrobe walls into severe dimensional discrepancies.

This guide is aimed at joiners and fitters looking to precisely adjust the tightening travel of cam locks to guarantee perfectly flush joints. Troubleshooting and correcting each joint takes around two to three minutes.

Required Tools & Materials

Proper installation and adjustment of cam fittings requires no specialised machinery, but exact hand tools are essential to avoid damaging the hardware:

Pozidriv screwdriver size PZ2 or a matching hex key, depending on the drive of the cam housing.
Vernier calliper to check drilling and insertion depths.
Rubber mallet for driving wooden dowels flush.
Cordless screwdriver with torque clutch (solely for inserting connecting bolts, never for tightening the cam).

Understanding the Mechanics of Cam Fittings

Before optimising the tightening travel, one must understand how the components interact. A standard cam connector consists of two main components: the connecting bolt (also known as a dowel or pin) and the cam housing (the cam lock casing).

The connecting bolt is screwed into the edge or face of the first panel. The cam casing sits in an exact blind hole in the second panel – usually with a diameter of 15 mm. The head of the bolt extends through an edge hole into the cam casing.

The cam works like a stepless mechanism that converts the rotational movement of the screwdriver into linear tensile pull. Turning the casing causes the internal, spirally rising curved track to grip beneath the head of the bolt. The further it turns, the tighter the cam pulls the bolt towards itself. This tightening travel typically spans 2 mm to 3 mm. If this travel is insufficient to pull the boards flush together, a mechanical preparation error is present.

Step-by-Step Guide: Optimising Tightening Travel and Eliminating Gaps

The following systematic approach ensures the maximum tensile force of the fitting is utilised.

Step 1: Check Dimensional Accuracy of Drill Holes

Most furniture fittings are based on the System 32 standard. Use a vernier calliper to check that the hole for the cam casing measures exactly 15 mm in diameter and has the correct depth (typically 12 mm to 14 mm, depending on board thickness, e.g. 16 mm or 19 mm). If the hole is too shallow, the casing protrudes and prevents the joint from closing flush. Any wood shavings in the drill hole must be thoroughly removed.

Step 2: Position the Connecting Bolt Accurately

The most common cause of open gaps is an incorrectly positioned bolt. The connecting bolt features a thread (often for 5 mm holes) and a collar. Screw the bolt in at a precise right angle. The collar of the bolt must sit completely flat against the panel surface. If it is driven too deep (collar sunk into the wood), the head will not extend far enough into the cam casing, causing the cam to spin freely without gripping. If it is not inserted deeply enough, the head hits the back of the cam casing before the panels meet. The tightening travel is then exhausted before the gap closes.

Step 3: Use Wooden Dowels for Alignment

Cam fittings withstand tensile forces but cannot handle shear forces. Additional wooden dowels (usually 8 mm in diameter) serve this purpose. Ensure the wooden dowels are not too long. An overly long dowel resting against the bottom of the opposing hole acts as a spacer. In this scenario, even tightening the cam with maximum force will not close the gap – instead, the cam casing will tear out of the board.

Step 4: Insert and Align the Cam Casing

Press the cam casing flush into the 15 mm hole. On the top of the casing, there is a small arrow. This arrow must point directly towards the front edge through which the bolt enters. Only in this position is the opening of the curved track ready to receive the bolt head.

Step 5: Utilise the Tightening Travel (Locking)

Bring the panels together. The bolt head must audibly or tangibly glide into the casing. Insert the PZ2 screwdriver. Turn the casing clockwise. The turning angle for optimal mechanical lock usually lies between 180° and 210°. Do not use excessive force. When the cam encounters noticeable resistance after roughly half a turn and the joint is closed, the connection is locked. Over-tightening (360°) destroys the internal curved track of the die-cast casing and ruins the fitting.

Common Mistakes When Fitting Carcass Connectors

Incorrect Tool Drive: Using a PH (Phillips) screwdriver instead of a PZ (Pozidriv) inevitably leads to slipping (cam-out). The soft zinc die-cast material strips, making subsequent retightening or disassembly impossible.
Crooked Bolt Insertion: If the bolt does not sit at a precise 90° angle in the panel, the head engages the curved track unevenly. The cam then pulls the boards together out of square, resulting in an uneven gap.
Lack of Counter-Clamping: On very large carcass components, such as those found in a two-person wardrobe, manual force is often not enough to push parts together. Use carcass clamps to pull panels flush before locking the cam. The cam is primarily intended for locking, not for drawing heavy, misaligned parts together over several millimetres.

After Carcass Assembly: Adjusting Hinges and Flaps

A perfectly square, seamlessly joined carcass is the mandatory prerequisite for subsequent door and front installation. If a carcass forms a parallelogram due to poor cam joints, cabinet doors can no longer be aligned properly.

Once the carcass is plumb and square, doors are adjusted via the concealed hinge. A standard concealed cup hinge (usually with a 35 mm cup hole) features three adjustment screws on the mounting plate and hinge arm:

Overlay Adjustment (Side Adjustment): Regulates the lateral door overlay. This sets the reveal gap between two doors (e.g. on a twin application) to exactly 2 mm to 3 mm.
Depth Adjustment: Moves the door closer to or further away from the carcass.
Height Adjustment: Raises or lowers the door, usually adjusted via slotted holes in the mounting plate.

For media units, such as a TV sideboard or a low TV unit, downward-opening drop-down flaps are frequently installed using flap stays or gas struts. When installing a gas strut for heavy flaps, matching the correct force in Newtons (N) to the exact weight of the MDF or solid wood front is crucial.

Exact carcass construction is equally vital for office or kitchen fittings. When a desk cable grommet is recessed into a top panel, that panel must rest completely flat on the side gables via the cam connectors beneath to prevent vibration. The same applies to wall units housing a wall cabinet dish drainer: moisture demands fully closed joints, otherwise water can penetrate the unsealed edges of the chipboard core.

FAQ: Frequently Asked Questions About Cam Connectors

Why is the cam not pulling the panels completely together? Usually, the connecting bolt is driven too deep into the wood, preventing the head from entering far enough into the casing. Alternatively, a wooden dowel is bottoming out in its hole, mechanically blocking the joint.

Can cam connectors be reused? Yes. Unlike glued joints, cams can be released by turning counter-clockwise. Provided the zinc die-cast casing is not stripped and the curved track remains intact, the hardware can be assembled and dismantled repeatedly.

Which dimension is critical when selecting replacement cams? The essential dimensions are casing diameter (standard is 15 mm) and board thickness (16 mm, 18 mm, or 19 mm). Board thickness dictates the height of the cam casing so that it sits flush with the panel surface after installation.