DUO System 26 x 26 – Concealed Table & Bed Frame Connector

The DUO 26×26 is the most compact connector in the DUO-System, engineered for smaller frame joints while maintaining the look of traditional joinery. Like all DUO connectors, it is non-visible, self-tightening, and can be assembled quickly without clamping.

Despite its small size, the DUO 26×26 provides reliable holding power with a tested load value of 0.97 kN (transverse force, insertion direction). This makes it ideal for lightweight frame applications such as chairs, tables, and interior furniture where clean design and stability are essential.

Features and Benefits

• Fast and efficient assembly – components hook together in seconds

• Non-visible connector for clean aesthetics

• Self-tightening design – adjustable with the included pan head screw

• Concealed connection appeals to architects and end users

• Reusable – can be disassembled and reassembled as needed

• Versatile – accommodates material shrinkage or swelling with re-tightening

• Tested and certified by Holzforschung Austria

• Chair frames

• Table frames and aprons

• Small interior furniture

• Architectural joinery requiring concealed connections

• Size: DUO 26×26 mm

• Material: Blue-galvanized, weather-resistant steel

• Load Value: 0.97 kN (transverse force, insertion direction)

• Mounting: By screwing with CS-screws Ø 5–6 mm (use 5×40, 5×60, 6×40, or 6×60 mm for commercial use per Ö-Norm M5027)

• Installation: Compatible with CNC machine, long hole drilling machine, or hand router

• Suitable Materials: Solid wood and plywood materials from 21 mm thickness

• Advantages: Concealed, self-locking, adjustable screw connector for frame connections

Steps

1. Cut the mortise using a 2-Flute Straight Router Bit (13/32″) combined with a Router Bushing (1″ OD) and the MULTI F Routing Jig.
   Note: Select the Routing Jig size according to the connector size. Optionally, use the Router Base Plate Adapter to hold the Router Bushing (1″ OD).

2. Use the Routing Jig to align and cut a 13 mm deep mortise into either the end-grain or face of the wood. Mortise width is preset; mortise length depends on connector size.

3. Place one DUO 26×26 connector plate into the mortise and use it as a jig to predrill screw holes.

4. Fasten the first connector plate with the screws provided.

5. Place the second plate over the first and insert the pan head screws until snug, setting the correct depth for tight assembly.

6. Secure the second connector plate with the screws provided.

7. Join the workpieces by tapping together with a rubber mallet.

Tips

• The joint remains tight thanks to the dovetail-like snap fit.

• The fastener design allows for natural wood movement (shrink/swell) and can be re-tightened if needed.