Hinge Cup Hole (35 mm Cup Diameter) — What Is It? Dimensions & Guide
The hinge cup hole is a cylindrical recess routed into the inside of a furniture door, designed to accommodate the hinge cup of concealed cabinet hinges. The industry standard diameter is 35 mm, whilst the drilling depth usually ranges between 11 mm and 13 mm depending on the hinge type.
What exactly is a hinge cup hole?
To mount a concealed hinge flush into a cabinet door, a precise recess is required. This routed pocket houses the metal cup of the hinge. Through this design, the mechanism sits securely in the substrate like a ball joint in its socket, enabling complex opening angles and 3D adjustment. The hole is drilled precisely at right angles into the base material (such as chipboard or MDF) using a dedicated Forstner bit or machine bit.
Dimensions, standards and spacings
When planning and manufacturing furniture fronts, exact dimensions are essential. Incorrect spacing causes the door to catch on the cabinet carcase when opened or prevents it from being adjusted correctly.
- Diameter: The standard for 35 mm concealed hinges is exactly 35 mm. For lightweight or very narrow doors, special versions with 26 mm are available.
- Drilling depth: The cut must be deep enough for the hinge cup, without piercing through the front. Standard depths range from 11.5 mm to 13 mm. With a standard door thickness of 19 mm, sufficient core material remains.
- Cup distance (C-dimension): This is the distance from the edge of the door to the perimeter of the cup hole. It varies depending on the desired reveal and overlay type, but generally sits between 3 mm and 6 mm.
Overlay types and hinge variations
The position of the hinge cup hole often remains identical across standard hinges, regardless of how the door rests against the carcase. The difference in closing behaviour is achieved by the cranked hinge arm.
- Full overlay: The door completely overlays the side panel of the carcase. For this configuration, full overlay concealed hinges are used.
- Half overlay: Two doors share a single central divider panel (twin overlay). The solution here is half overlay concealed hinges.
- Inset: The door sits flush inside the cabinet carcase opening. Inset concealed hinges (often referred to as concealed hinges for inset doors) are fitted for this application.
Beyond the overlay type, the kinematics determine the opening angle. Standard doors frequently use 110 degree concealed hinges / cabinet hinges. For wide-angle applications, such as internal drawers, 155 degree concealed hinges / cabinet hinges or 165 degree concealed hinges / cabinet hinges are required. Modern versions integrate a damper directly into the hinge cup. Such concealed hinges / cabinet hinges with damping (Soft Close) gently cushion the closing movement.
Tools and installation advice
To produce a clean hinge cup recess, a Forstner bit with a 35 mm diameter is the standard tool. To prevent tear-out in chipboard, work at high rotational speeds with moderate feed pressure. A drill stand or pillar drill guarantees an exact perpendicular hole. The hinge is secured in the hole typically with two lateral screws (often 45 mm hole spacing) or tool-free via clip-on mounting using expanding dowels.
Related terms in furniture construction
- System 32: Standardised grid system for hole lines in furniture making with 32 mm spacing.
- Cruciform mounting plate: The counterpart to the concealed hinge, which is screwed to the interior of the cabinet carcase.
- Soft-close: Damping mechanism for quiet closing. Not to be confused with push-to-open (a mechanical opening support for handleless fronts).
Matching categories
All relevant fittings for mounting on furniture fronts as well as matching mounting plates can be found in the technical overview for concealed hinges / cabinet hinges.