Spigot Truss Accessories: A Complete Guide to Clamps and Couplers

August 13, 2026

When building a staging or rigging system with spigot truss, the structural tubes and welded joints get most of the attention. But the clamps and couplers that connect truss sections, attach accessories, and tie the system to rigging points are just as critical to safety and performance. This guide covers what you need to know about spigot truss accessories, with references to our WRF, WRT, and WRS truss lines.

What Are Spigot Truss Accessories?

Spigot truss (also called pin or cone truss) uses a tapered spigot that slides into the end of an adjacent section, secured by a locking pin. Accessories such as clamps and couplers serve several functions:

Joining truss sections – couplers align and lock sections together, ensuring a continuous load path.
Suspending truss – clamps attach to the main tube and provide a connection point for hoists, motors, or chain blocks.
Mounting equipment – clamps hold lighting fixtures, speakers, or banners onto the truss.
Bracing – couplers can be used to connect diagonal braces to increase stability.

Because spigot truss is modular, the accessories must be compatible with the specific tube diameters and wall thicknesses of the truss. For example, our WRF-29 ladder truss uses a 50x3mm main tube, while the WRT-29 triangle truss uses a 50x3mm main tube as well. Always verify that your clamps are rated for the tube size and wall thickness.

Types of Clamps and Couplers

Half Couplers and Swivel Couplers

Half couplers attach to a single tube and provide a fixed or swivel connection point. They are commonly used to hang truss from a beam or to attach a light bar. Swivel couplers allow rotation for angled setups.

Sleeve Couplers

Sleeve couplers slide over the outside of two adjacent tube ends, providing a rigid connection. They are often used with spigot truss to reinforce the joint, especially for longer spans.

Base Plates and Feet

Base plates attach to the bottom of a truss tower to distribute load to the ground. They are essential for freestanding structures.

Spigot Connectors

These are the integral spigots on each truss section. While not a separate accessory, they are the primary joining mechanism. For example, our WRS-29 square truss has spigots on each end, allowing sections to be connected quickly.

How to Choose the Right Accessories

1. Match Tube Diameter and Wall Thickness

Clamps are sized by the outer diameter of the tube they grip. For our trusses, the main tube is 50x3mm across all models listed. This means a clamp designed for 50mm OD will fit, but the wall thickness affects the clamp's grip and load rating. Check the manufacturer's specifications.

2. Consider Load Requirements

Accessories must be rated for the loads they will carry. Use the load tables for your truss to determine the maximum load at your span. For instance, the WRS-40 square truss has a distributed load capacity of 936 kg/m at 3 meters, but only 176 kg/m at 8 meters. Your clamps must be rated for the point loads you intend to apply.

3. Think About Compatibility

Not all spigot trusses are the same. Our WRF-29 ladder truss, WRT-29 triangle truss, and WRS-29 square truss all share a 50x3mm main tube, so some accessories may be interchangeable. However, the WRS-4060 and WRS-5060 have different dimensions, so always verify compatibility.

4. Safety Factors and Certification

Look for accessories that are tested and certified. Our trusses are TÜV-tested, and we recommend using accessories from reputable manufacturers that provide load ratings. Never mix unrated or mismatched components.

Practical Applications

Concert and Event Staging

For a 6-meter span using WRS-29 square truss, the distributed load capacity is 317 kg/m. You can use clamps to hang lighting fixtures along the truss, but ensure the total load does not exceed the capacity. A half coupler on the main tube can support a single fixture, while a swivel coupler allows aiming.

Trade Show Booths

Lighter trusses like the WRF-29 ladder truss are ideal for small booths. With a 3-meter span, it supports 168 kg/m distributed load. Use base plates and couplers to create a freestanding structure, and attach banners with clamps.

Rigging and Suspension

For heavier loads, the WRS-4060 square truss supports 403 kg/m at 6 meters. Use heavy-duty clamps designed for 50mm tube to connect to hoists. Always use a safety factor of at least 5:1 for overhead suspension.

Sourcing from a Factory

When buying spigot truss accessories directly from a factory, consider the following:

Material quality: Our trusses are made of 6082/6061-T6 aluminum, which offers high strength-to-weight ratio. Accessories should be made of similar quality aluminum or steel.
Finish: Anodized or powder-coated finishes resist corrosion, important for outdoor events.
Certifications: Look for TÜV or ISO certifications. Our factory holds ISO 9001:2015.
Customization: Factories can often produce custom lengths or special clamps. For example, our WRS-52 truss is available in lengths from 50 cm to 400 cm.

FAQ

Q: Can I use the same clamps for WRF-29 and WRS-29 trusses?

A: Yes, because both have a 50x3mm main tube. However, always check the load rating of the clamp against your application.

Q: What is the difference between a half coupler and a swivel coupler?

A: A half coupler provides a fixed connection point, while a swivel coupler allows rotation. Swivel couplers are useful for aiming lights or adjusting angles.

Q: How do I know the maximum load for my truss span?

A: Refer to the load tables. For example, the WRS-30 square truss at 4 meters has a distributed load capacity of 488 kg/m and a point load of 1466 kg. Always use the lower of the two if both apply.

Q: Are your trusses and accessories TÜV certified?

A: Our trusses are TÜV-tested. For accessories, we recommend using certified components from reputable suppliers. Contact us for specific accessory certifications.

Conclusion

Choosing the right spigot truss accessories is about matching the clamp or coupler to your truss's dimensions and load requirements. By understanding the types of accessories and using the load data provided, you can build safe and reliable structures. For more details on our truss models, visit our product pages:

If you have specific accessory needs, our factory can provide guidance and custom solutions.