Adjusting Magnetic Catches: Setting the Optimum Holding Force for Secure Cabinet Doors
A magnetic catch secures handleless or easy-running cabinet doors using magnetic holding force, with the precise alignment of the magnet housing and counter plate achieved via slotted holes down to the millimetre.
Correct installation and adjustment of these components are vital for clean gaps and the secure closing of furniture fronts. When cabinet doors rattle, pop open on their own, or have uneven gaps, the issue is usually poor coordination between the hinge and the closing mechanism. This guide is aimed at fitters, joiners, and keen DIYers who want to align cabinet doors accurately and optimise the holding force of magnetic catches.
The difficulty of this task is rated as easy to moderate. When carried out properly, it takes around 10 to 15 minutes per cabinet door.
Required Tools and Materials
For precise adjustment and installation, no specialised machinery is required, but properly fitting hand tools are essential to avoid damaging screw heads.
- Pozi screwdriver (size PZ2 for standard hinge screws, PH1 or PZ1 for the small fixing screws on the catches)
- Tape measure or folding rule
- Vernier caliper for exact depth measurement
- Bradawl or pencil for marking
- Spare screws (typically chipboard screws with a 3 mm or 3.5 mm diameter)
- Matching magnetic catches with the required pull force
Preparation: The Foundation for the Magnetic Catch
Before working on the magnetic catch, the cabinet door must hang completely plumb, level, and flush with the carcass. A magnetic catch cannot correct a crooked door. The contact between the magnet and the counter plate works like a precision clutch in a gearbox; full force is only transferred when both surfaces meet entirely flat.
Therefore, it is essential to check and adjust the hinges first. Most modern furniture uses a concealed cup hinge (usually with a 35 mm cup diameter). Depending on the cabinet construction, this will be a full overlay (door completely covers the carcass side), a half overlay (door shares the carcass side with an adjacent door), or an inset door (door sits flush between the carcass sides).
Adjusting Cabinet Doors: 3D Adjustment on the Concealed Hinge
To adjust cabinet doors, use the adjustment screws on the hinge arm.
- Height adjustment: Slightly loosen the fixing screws on the mounting plate (the plate screwed to the carcass). On plates with slotted holes, you can now move the door up or down by about 2 mm. On modern cruciform mounting plates, this is often done via an eccentric screw in the centre without loosening the main screws.
- Side adjustment (gap alignment): The front screw on the hinge arm regulates the lateral position. Turning it clockwise moves the door towards the hinge side. Turning it anticlockwise widens the gap. Adjust all hinges so that the reveal runs parallel.
- Depth adjustment: The rear screw on the hinge arm sets the depth. Loosen it slightly to pull the door away from the carcass or push it closer. This is the most crucial step for subsequent magnet operation. The gap between door and carcass when closed should consistently be around 1.5 mm to 2 mm.
Only once you have finished adjusting the concealed hinge and the front sits straight should you proceed to fine-tune the catch.
Step-by-Step Guide: Adjusting the Magnetic Catch
The mounting position of the catch is typically on the side opposite the hinge. On very tall doors, such as those often found on a double wardrobe, fitting two catches (top and bottom) is recommended to prevent the front from warping.
Step 1: Check the Counter Plate Position
The metal counter plate is screwed to the inside of the door. Check whether this plate sits at the exact height of the magnet housing. If the plate is rigidly fixed, it serves as the reference point. If it is a floating plate (often secured with a single central countersunk screw), ensure it has slight play. This play allows the plate to align perfectly flat against the magnet upon closing.
Step 2: Loosen the Fixing Screws on the Magnet Housing
The housing of the catch is usually attached to the furniture carcass with two screws through a slotted hole. This slotted hole is the key adjustment mechanism. Loosen the screws by about half a turn using a suitable screwdriver. The housing should now slide forwards and backwards with slight resistance.
Step 3: Set the Optimum Depth
First, push the magnet housing about 2 mm further forward (towards the front of the unit) than seemingly necessary. Now close the door slowly. The counter plate on the door will touch the magnet, and the pressure of the closing door will push the housing within the slotted holes into the exact position required for a flush front finish.
Hold the door closed in this precisely flush position. Do not press too hard, or the front may flex.
Step 4: Secure the Housing
Open the door very carefully so you do not knock the magnet housing out of its new position. Now tighten both screws in the slotted holes securely. Take care not to overtighten them, as this can strip the thread in the chipboard.
Step 5: Function Check
Close the door normally. It should engage against the magnet with solid, audible contact. The door front must now sit flush with the adjacent edges of the carcass. If the magnet pulls the door in too far, loosen the screws again and reposition the housing approximately 1 mm further forward.
This technique applies to virtually all furniture units. On handleless living room designs, such as a TV sideboard, precise alignment is particularly crucial, as uneven gaps are immediately noticeable.
Common Mistakes During Fitting and Adjustment
Although the principle is simple, mistakes that compromise the holding force occur frequently in practice.
Mistake 1: Rigid counter plate meets rigid magnet If the counter plate on the door is fixed completely rigidly with two screws and is not 100% parallel to the magnet, the components will only touch along one edge. The magnetic holding force drops drastically as a result. Solution: Use counter plates with a single, central fixing screw and do not tighten it fully. The plate needs slight movement to self-align.
Mistake 2: Hinge springs fighting the magnet A standard concealed hinge has an integrated closing spring. If you adjust cabinet doors and the depth is set so tight that the door hits the carcass before the magnet catches, the hinge spring will push the door back open. Solution: Increase the gap on the hinge side to at least 1.5 mm.
Mistake 3: Using the wrong screw heads If raised-head screws are used instead of countersunk screws for the counter plate, the screw head will project above the metal plate. The magnet hits the screw head rather than the flat surface of the plate, creating an air gap. Solution: Use only countersunk screws (typically 3 mm diameter) that sit completely flush in the countersunk hole of the counter plate.
Specialist Applications in Furniture Assembly
Not all cabinet carcasses are constructed the same way. Requirements for closing mechanisms vary depending on the installation environment.
In kitchens, for instance inside a wall unit housing a wall cabinet plate rack, catches often need to withstand humidity. In this case, encapsulated plastic housings are recommended. Adjusting the cabinet doors follows the same principle, but the holding force should be higher (e.g. 40 Newtons), as these doors are operated more frequently and with greater momentum.
For downward-opening flaps on a TV lowboard, magnetic catches serve purely to secure the flap in its closed position. When opening, the weight of the flap must be supported by dedicated flap stays or cable stays. For upward-opening fronts, gas struts for heavy flaps are often used instead of catches, as they not only hold the front shut but also actively push it upwards and bear its weight.
Frequently Asked Questions
Why does the door not stay shut even though the magnet is strong enough? This is almost always caused by an air gap between the magnet and the counter plate. Even a gap of 0.5 mm drastically reduces magnetic pull. The root cause is usually a misaligned door. You must adjust the furniture hinges before adjusting the magnet.
Can I combine a magnetic catch with door dampers? A standard magnetic catch is difficult to combine with a soft-close system (damping). The damper slows the door down, leaving it without the momentum required to overcome the magnet's resistance and pull fully flush. For damped doors, hinges with integrated closing springs should be used without an additional magnet.
How much holding force (in kg) does a catch require? Holding force is often specified in kilograms (kg), though the technically correct unit is Newtons (N). For a standard cabinet door (MDF or chipboard, approx. 600 mm x 400 mm), a pull force of 2 kg to 4 kg (approx. 20 N to 40 N) is entirely sufficient. For solid oak doors, a model with 5 kg to 6 kg should be selected.
The screws in the slotted hole keep spinning, what can I do? If the thread in the chipboard has stripped, the screw will no longer bite. Drill out the hole using a 5 mm drill bit and glue in a standard wooden dowel. Once dry, you can drive the screw securely into the dowel again and complete the door hinge adjustment.