Tandembox & Metabox: Drawer Systems & Matching Runners (Compatible with Blum)
Tandembox and Metabox refer to established drawer systems featuring double-walled or single-walled metal sides that operate on matching runner profiles. A Tandembox utilises concealed undermount runners for a smooth running action, whilst the Metabox is based on robust roller runners. Both systems require precisely matched runners regarding nominal length and load capacity.
What are Tandembox and Metabox Exactly?
In the construction of cabinets in furniture making, drawer systems form a functional unit consisting of the drawer side (profile), back panel, base, and the corresponding runner. The systems differ fundamentally in their technical design:
The Tandembox is characterised by a double-walled steel side. With this system, the runner is mounted completely underneath the drawer base. This concealed technology protects the mechanism from dust and debris and provides a sleek appearance inside the drawer.
The Metabox, on the other hand, is a system with a single-walled side profile. In this case, the running track contour is integrated directly into the side wall of the drawer. The system functions like the chassis of a car: the metal side forms the bodywork, whilst the integrated runner provides the direct drive for the movement.
Runner Types and Extension Options
The choice of runner determines the extension travel and the smooth operation of the drawer. Both systems require different types of runners:
- Tandem runners: These utilise undermount drawer runners based on a roller or ball bearing system. They are frequently designed as full-extension drawer runners, allowing the drawer to be pulled 100% out of the cabinet.
- Metabox runners: This system operates on roller runner drawer runners with plastic rollers. Due to their design, these are usually partial extensions, which can only be pulled out by around 75%.
Motion Technologies: Soft-Close vs. Push-to-Open
Modern runners are equipped with specific mechanisms that are mutually exclusive in their function:
- Soft-Close: A hydraulic or pneumatic damper slows the drawer down over the final few centimetres and pulls it shut gently and silently. Matching drawer runners with soft-close absorb the momentum. A simpler mechanical variant without a damping cylinder is drawer runners with self-closing action.
- Tip-On: This mechanism is designed for handleless fronts. Push-to-open drawer runners mechanically pop the drawer open with a light press on the front.
Dimensions, Standards and Typical Values
For assembly in the workshop or on-site, precise installation dimensions and load limits are crucial. The drilling holes in the cabinet carcass generally follow System 32 (32 mm hole spacing, 5 mm hole diameter).
- Nominal lengths: The length of the runners typically ranges from 270 mm to 650 mm. Common standard dimensions in kitchen manufacturing include, for example, 500 mm drawer runners.
- Load capacity: Standard Tandembox runners are designed for a dynamic load of 30 kg. For wide pull-outs or heavy cookware, heavy-duty drawer runners with a load capacity of 50 kg to 65 kg are installed.
- Cutting dimensions: When constructing the unit, the wooden base and back panel must be calculated accurately. The standard material thickness for the base and back panel in these systems is 16 mm.
Usage & Selection
When selecting replacement parts or planning a new project, the nominal length of the runner must match the length of the drawer side exactly. A 500 mm drawer side strictly requires a 500 mm runner. In addition, the internal cabinet width must be measured to calculate the correct width for the wooden drawer base. The drawer front is fixed using special brackets that allow three-dimensional adjustment (height, side, tilt) in millimetre increments.
Related Terms
- Drawer side (Zarge): The lateral metal boundary of the drawer in these systems.
- Front fixing bracket: The connector between the drawer side and the wooden front.
- Gallery rail: A longitudinal rail mounted above the drawer side on high fronts (e.g. pan drawers) to prevent stored items from falling out.
- System 32: An international standard in furniture construction for the spacing of line boring holes.