How to Install a Cruciform Mounting Plate: Guide for Blum-Compatible Hinges
The cruciform mounting plate connects the concealed hinge to the inside of the cabinet carcase and determines the exact door reveal via its height distance (D value).
The correct installation of hinges is decisive for clean gaps and the smooth kinematic operation of a furniture front. Installing plates that are compatible with Blum systems requires precise measuring and drilling. This guide is aimed at installers and experienced furniture makers. It covers positioning, drilling in the 32 mm system, and the final adjustment of the cruciform mounting plate in combination with a standard concealed hinge.
With tools prepared, the installation time per hinge point is around five to ten minutes.
Required Tools and Materials
For the professional installation of a cruciform mounting plate, you will need the following equipment:
- Cruciform mounting plate (compatible with Blum hinges, e.g. distance 0 mm)
- Matching concealed hinge (e.g. for full overlay with an opening angle of 110°)
- Cordless drill/driver
- Matching screwdriver bits: PZ 2 (Pozidriv) for adjustment screws and Euro screws, or alternatively TX 20 (Torx) depending on the screw head
- Euro screws (Ø 5 mm) or chipboard screws (Ø 3.5 mm)
- Wood drill bit with centring tip (Ø 5 mm for Euro screws, Ø 2.5 mm for pre-drilling wood screws)
- Try square, folding rule, and pencil
- Centre punch or bradawl
Preparation: The 32 mm System and Distance
Before the first drill bit touches the wood, the theoretical position of the mounting plate must be determined. In industrial and bespoke furniture production, hardware installation is almost always based on the 32 mm system.
This means:
- The distance between the drill holes is exactly 32 mm.
- The distance from the front drill hole to the front edge of the carcase is 37 mm as standard.
Choosing the Correct Distance (D)
Cruciform mounting plates are available in various thicknesses, specified as distance D (usually 0 mm, 3 mm, 6 mm, or 9 mm). The required distance is calculated from the desired front overlay (how far the door covers the carcase side) and the cup distance (the measurement between the hole in the door and the door edge).
For a classic full overlay with a 19 mm thick carcase side and a cup distance of 4 mm to 5 mm, a mounting plate with a distance of 0 mm is generally used.
Step-by-Step Guide: Installing a Cruciform Mounting Plate
1. Mark the Height Position on the Carcase
The height of the cruciform mounting plate must align precisely with the height of the hinge cup hole (usually Ø 35 mm) in the cabinet door. Measure the distance from the top or bottom edge of the door to the centre of the cup hole. Transfer this measurement to the inner face of the carcase side panel. Be sure to account for the planned reveal (e.g. a 2 mm gap between the door and the top edge of the carcase) when measuring.
2. Mark the Depth Position and Drill Points
Using a try square, draw a vertical line exactly 37 mm from the front edge of the carcase. Mark the centre (the previously determined height) on this line. From this centre mark, measure 16 mm upwards and 16 mm downwards. Mark these two points. You have now marked out the 32 mm hole spacing. Use a bradawl to mark the centres lightly. This prevents the drill bit from slipping.
3. Drill the Fixing Holes
The choice of drill bit depends on the screws being used:
- For Euro screws: Drill using a 5 mm wood drill bit. The drilling depth should be around 13 mm to 14 mm for a 19 mm thick carcase side. Use a depth stop on the drill bit to avoid drilling through the side panel.
- For chipboard screws: Pre-drill using a 2.5 mm bit to a depth of approximately 10 mm.
Note on clearance checks: When planning drill points, ensure that the hinge will not collide with interior pull-outs. For example, if you are installing drawer systems or undermount drawer runners in the same cabinet, the hinge arm must sit outside the operating path of these components.
4. Screw on the Mounting Plate
Position the cruciform mounting plate. Pay attention to the orientation: the small arrow on the plate must point towards the front edge of the carcase. Screw the plate into place. Tighten the screws hand-tight to avoid stripping the thread in the chipboard.
5. Clip on the Hinge
If you are using a modern hinge with a clip-on mechanism, the connection is tool-free. Clipping on the hinge arm functions like a ski boot binding: first locate it onto the front of the mounting plate, then press the rear part down until it engages with an audible click. Check that it is securely seated by pulling lightly on the hinge arm.
3D Door Adjustment
Once all hinges are connected to the mounting plates, fine adjustment of the door can take place. Cruciform mounting plates compatible with Blum systems offer three-dimensional adjustment when combined with the hinge.
- Height adjustment: Loosen the two fixing screws on the cruciform mounting plate slightly (or use the cam adjustment screw on the plate, if present). The door can now be shifted by approximately +/- 2 mm up or down. Retighten the screws.
- Side adjustment: Turn the front screw on the hinge arm. This moves the door left or right across the carcase edge, regulating the side reveal.
- Depth adjustment: Loosen the rear screw on the hinge arm (on newer models, this is often a cam screw that only needs turning rather than loosening). The door can now be moved closer to or further away from the carcase. The optimal gap between door and carcase is around 1.5 mm to 2 mm to ensure the door does not rub against the carcase side when opening.
Common Installation Mistakes
Wrong screwdriver bit: A classic mistake is using a PH (Phillips) bit for screws with a PZ (Pozidriv) drive. Mounting plates and hinges almost exclusively use PZ 2. The wrong bit will damage the screw head, making later removal or adjustment extremely difficult.
Mixing up overlay types: The mounting plate must match the hinge type. A hinge for a half overlay (twin application) has a different crank than one for an inset door. If you clip the wrong hinge onto the plate, the door will not close.
Combining mismatched kinematics: Soft-close mechanisms and opening mechanisms must not be confused. A hinge with integrated soft-close gently pulls the door shut over the final centimetres. This works well alongside soft-close drawer runners in the same unit. However, if you are planning handleless fronts, you need an unsprung hinge without soft-close, combined with a push-to-open latch. This is the exact opposite operating principle, comparable to the mechanism found in push-to-open drawer runners.
Relevant Hardware for Complex Carcase Systems
Selecting the correct hinge and mounting plate depends heavily on the weight and function of the door. For very tall or heavy MDF fronts, the standard number of two hinges is often insufficient. In these cases, three to four mounting plates must be positioned within the exact 32 mm grid to distribute the load evenly. This principle of load distribution applies across furniture construction—just as heavy drawers require heavy-duty drawer runners to absorb leverage forces.
If the front is an upward-opening flap rather than a standard hinged door, cruciform mounting plates are generally not used. In this scenario, installers use flap fittings or gas struts for heavy flaps, where the force in Newtons (N) must be matched precisely to the weight of the front.
Frequently Asked Questions
What distance must the line of holes have from the front edge? For standard cruciform mounting plates, the drilling distance from the front edge of the carcase to the centre of the holes is exactly 37 mm. This applies to overlay doors (full overlay and half overlay).
What changes with inset doors? When the door is fitted inset (inset application), the mounting plate moves further back. The 37 mm measurement is added to the thickness of the furniture door. For a 19 mm thick door, the drilling line is therefore 56 mm from the front edge.
Can I use an old mounting plate with a new hinge? Only if the system is identical. The locating points for clip-on mounting vary between manufacturers and often across different product generations of the same brand. A plate designed for Blum Clip Top will only securely accept the matching hinge arms.
Why will the hinge not clip onto the plate? Check whether the fixing screws of the mounting plate are driven in flush. If a screw head protrudes, it will block the mechanism on the hinge arm. Additionally, the hinge arm must be positioned completely straight when clipping on.