How Wide is A Lighting Truss? The Ultimate Guide to Choose Lighting Truss

Choosing between a 290mm, a 400mm, or a 520mm lighting truss feels like a simple math problem until you are actually on site. The numbers on the spec sheet are great, but the reality of the load and the span and the wind outside is a whole different beast. Most people start with the 290mm because it is easy to move, but they quickly realize that the 400mm and 520mm lighting trusses exist for a reason. Here is the thing. You need to know exactly what each one can handle before you start hanging expensive gear. Ultimately, picking the right lighting truss is the foundation of a safe and professional stage setup.

Common Lighting Truss Sizes

Here is a quick look at the standard sizes (Spogot Lighting Truss) you will see in the field most often.

If you want to understand why these truss widths matter so much, we need to know about the physical reality of these systems. The following sections will explain how each size behaves when you actually put it to work as a reliable truss for lights.

Which Lighting Truss Width Actually Fits Your Needs?

The width of a lighting truss is not just about aesthetics or how it looks in the air. It is entirely about the physics of load distribution and how much weight that aluminum can take before it starts to fail. When we talk about width, we are talking about the distance between the main chords. A wider truss has a better ability to resist bending forces. On a stage, we just call it strength. If you go too thin, you get deflection. If you go too wide, you are wasting money and truck space.

• 290mm Lighting Truss: Your Everyday Workhorse

The 290mm lighting truss is the industry standard for a reason. It is the size that almost every rental house keeps in stock by the hundreds. You can throw it in the back of a small van and one person can carry a two meter section without breaking their back. For small events like weddings or local theater productions, it is perfect. It was always used for countless DJ booths and small trade show displays. It can handle a decent amount of LED pars and maybe a few smaller moving heads without any issues. It is a nice choice when you need a clean look and you are not trying to bridge a massive gap.

But here is what people miss about the 290mm size. It has its limits. People see that 50mm main tube and think it can hold anything. But the narrow width means that as your span increases, your load capacity drops off a cliff. If you try to push this size beyond its 12 m limit, you may be asking for trouble. When your span is getting close to that maximum limit, it is definitely not a good idea to hang particularly heavy LED screens or massive audio equipment from it. Many people try to save a little cash by using a 290mm lighting truss for projects that clearly called for a larger size. The risk of having your structure bend and compromise the safety of the event is simply not worth the few dollars you might save on the rental or purchase price.

• 400mm Lighting Truss: When You Need More Muscle

When you move up to the 400mm lighting truss, you are entering a different world. This is where things start to get serious. That extra hundred millimeters of width provides a massive boost in rigidity. If you are doing a medium sized concert or an outdoor event with a roof system, this is usually your starting point. 400mm lighting truss is the sweet spot for professional rigs. You can hang a full row of high power moving heads and it will stay as straight as a board.

Think about a car show or an outdoor festival. You have wind to deal with. You have longer distances to cover between your towers. A 400mm lighting truss can span 14 m and still feel solid. It is the difference between feeling confident in your rig and constantly checking the load tables every time a fixture moves. Honestly, it just looks more professional on a larger stage.

• 520mm Lighting Truss: Built for the Big Events

The 520mm lighting truss is for stadium tours and massive festivals. When you see those large LED screens that weigh thousands of kilos or those massive line array speakers hanging from the truss roof, they are almost always on a 520mm or larger system. This size is built to handle the heaviest loads over the longest spans. It is the heavy hitter of the staging world.

Working with a 520mm lighting truss is a different game entirely. You are not moving these sections by hand. It is recommended to use forklifts and motors and a crew that knows exactly how to handle heavy aluminum truss. The sheer weight of the truss itself is a factor in your load calculations. If you are building a massive roof system for a headliner, this is what you want. It provides the kind of stability that allows you to sleep at night even when the weather turns nasty.

Bolted vs. Spigot: How Your Lighting Trusses Connect

Once you have decided on the width, you have to decide how those pieces are going to connect together. There are two main ways to join a lighting truss. You either use bolts or you use a spigot system. Both have their fans and both have their place in the world. It really comes down to how often you plan on moving the gear and how much you want to spend on labor.

• Why Touring Crews Love the Spigot Lighting Truss

The spigot lighting truss is the king of the road. It uses a pin system that is fast and easy to use. You just line up the ends, put in the spigot, and hammer in the pins. No tools required other than a simple hammer. This is why touring crews love it. When you have a load out at two in the morning and everyone is exhausted, you do not want to be fumbling with nuts and bolts. You just want to knock the pins out and get the truck loaded.

Anyway, the real beauty of the spigot system is the speed. It saves so much time on the setup and the strike. And because the pins are tapered, the connection is incredibly tight. There is no wiggle room at the joints. For rental companies and touring acts, the labor savings alone make the spigot lighting truss worth the extra cost.

• When a Bolted Lighting Truss Makes More Sense

But do not count out the bolted lighting truss just yet. It might be slower, but it has its advantages. You will mostly see these in permanent installations. Think about clubs or houses of worship or theaters. If you are going to put the truss up once and leave it there for at least five years, why pay for the expensive spigot system? A bolted connection is incredibly secure. Once those bolts are tightened down, that truss is not going anywhere. It is a very simple and very reliable way to build a grid.

If you are on a tight budget, the bolted lighting truss is often the way to go. The manufacturing process is a bit simpler so the price point is usually lower. It is a great option for a school auditorium or a small local theater where they have more time than money. You just have to be prepared for the extra work. You need wrenches and you need patience. But for the right application, it is a perfectly valid choice.

Safety and Material Quality: What Your Lighting Truss Is Actually Made Of

We need to talk about what is actually inside that aluminum. Because at the end of the day, you are hanging heavy things over people's heads. Safety is not just about the width of the truss. It is about the quality of the metal and the skill of the person who welded it together. If the material is garbage, it does not matter how wide the truss is. It will eventually fail.

• Why Aluminum 6082-T6 Makes a Difference

When you are looking at specs, you will see numbers like 6082-T6. This is not just random code. It is the grade of the aluminum alloy. In the staging world, 6082-T6 is the gold standard. It is a high strength alloy specifically designed for structural applications. It is stronger than the 6061 grade. It resists bending and it can handle the stresses of constant loading and unloading much better.

When you heat up aluminum to weld it, you actually weaken the metal around the joint. A good 6082-T6 alloy is designed to handle this process better. It maintains more of its strength after welding than other alloys. This is why you should always ask your supplier exactly what grade of metal they are using. If they cannot give you a straight answer or if they try to tell you it does not matter, please walk away. Your safety and the safety of your crew depend on the quality of that metal.

• Knowing When to Retire a Lighting Truss

You should be looking at your gear every single time it comes back from a show. It is recommended to check the welds first. Look for tiny cracks or any signs of discoloration. If a weld looks like it is pulling apart, that piece of lighting truss is dead. Do not try to fix it. Please pull it from service and cut it so that nobody else can use it. It is not worth the risk.

Are the main chords obviously bent? Are the diagonals looking asymmetric or twisted? If the holes do not line up when you are trying to put the pins in, you know the metal has stretched from too much weight in the past. You also need to keep a sharp eye out for cracked welds where the joints are starting to split. If you see any of these signs, pull that section from service immediately. Honestly, it is much better to be a piece of gear short than to have a whole rig come down on someone.

Span and Deflection: The Two factors That Actually Drive Your Decision

Now we get to the part that people find the most confusing. Span and deflection. These are the two factors that will actually tell you which width of lighting truss you need. If you ignore these, you are just guessing. And guessing is how accidents happen.

• How to Think About Span and Deflection for Your Lighting Truss

Span is simple. It is the distance between your two support points. If you have two truss towers twenty meters apart, your span is twenty meters. But as that span gets longer, the truss will bend in the middle. This bend is what we call deflection. Every manufacturer provides a load table that shows exactly how much safe weight you can hang at different spans and how much the truss will deflect. You need to read these tables carefully.

Have you ever seen a piece of aluminum bend like it was made of plastic? That is what happens when you ignore deflection. Even if the truss does not break, a big visible sag in the middle of your rig looks terrible. It makes the audience nervous and it makes you look like an amateur. The rule of thumb is simple. If you have a long span, you need a wider truss to keep that deflection under control. A 520mm truss at twenty meters will have less sag than a 400mm truss at the same distance. Always consult your truss manufacturers about the expert advice before you finalize your design. It is the best way to be sure your lighting truss will perform the way you need it to.

Getting the Right Lighting Truss from a Reliable Manufacturer

Picking the right lighting truss is about balance. You have to balance the needs of the show with the limits of your budget and the reality of your transport situation. But if there is one thing you should never compromise on, it is safety. Whether you choose 290mm, 400mm, 520mm or larger trusses, make sure you are getting the right truss for lights from trusted manufacturer. There are a lot of cheap choices out there that do not have the certifications or the testing to back them up.

Building a relationship with a solid manufacturer is worth its weight in gold. You want someone who can answer your technical questions and who understands the pressures of the event industry. Look for truss manufacturers that have been around for a while and have a track record of supporting their customers. They should be able to provide you with full load tables and material certifications for every piece of gear they sell. If they seem more interested in making a quick sale than in helping you build a safe rig, that is a red flag.

The best thing you can do is plan ahead. Do not wait until the week of the show to figure out if your lighting truss can handle the weight. Take the time to do the math and talk to your riggers. And if you are still not sure which size is right for your next project, reach out to GF-Truss. We love talking about this stuff and we are always happy to help you put together a custom plan that keeps your show in the air and your crew safe. Truss is a great industry to be in, so let's make sure we keep it that way by using the right tools for the job.