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Grip Equipment
This article gives a broad overview of box truss specifically for grips in the film industry. It is by no means a comprehensive guide for all types of truss and their load ratings and does not cover use cases from all industries. Always be sure to check the manufacturer’s specific load charts before using truss and deal with professionals. Load charts are not interchangeable between manufacturers.
Introduction
Box truss is used everywhere across the theatrical, live event, and film industries. You’ll find truss pretty much anywhere lights need to be hung. But as grips in the film industry, we use truss for a lot more than just hanging fixtures.
Did you ever play with Lincoln Logs growing up? (I’m convinced most grips come from a background of LEGO, Lincoln Logs, and K’Nex.) We build structures with truss, use it as spans for pick points, camera rigs, and so much more.
There are tons of different truss types, accessories, applications, and use cases—and sometimes it feels like a classic case of “you don’t know what you don’t know.” I’m always bookmarking and collecting reference material. Even if I don’t know the exact solution in the moment, knowing it exists makes it easier to track down later—a mindset I apply constantly in advanced gripping.
Bookmark this page as your go-to truss reference so you’ve always got it when you need it.
In this article, I’ll cover an overview of box truss and break down key topics:
What is box truss?
Different types and sizes
Key terminology
Orientation
Rigging methods & slings
Safety checklists
Applications in the film industry
Manufacturers
Accessories
30'x30' box truss day blue flyswatters in the air
What Is Box Truss?
Let’s start off with the basics - what is box truss? Box truss is a structural rigging element made out of aluminum with four main chords connected by diagonal bracing. This 4 chord truss is the “default” box truss. While it is worth noting that some box truss can come with 5 chords and there are many different box truss sizes, as film industry grips we mainly use 2 different “default” 4 chord truss sizes - more on that later in the sizes section. Box truss is manufactured in both steel and aluminum, but in the entertainment industry we’re mainly working with aluminum 99% of the time because of its durability, light weight, and ease of transport. Truss design and manufacturing has changed throughout the years and has evolved to support the growing demands of the industry. Today’s demands emphasize loading, span, lifting, easy of assembly, and cost.
ANSI E1.2-2021 covers specifications for the regulation of aluminum trusses, towers, and the associated aluminum structural components we use in the film industry in portable structures. It recommends that a qualified person perform inspections at least twice a year and that truss owner keep inspection records on file for each truss component. Inspection isn’t just left to the twice a year owner inspection - before each use a competent person has the responsibility to perform a visual inspection.
Competent person: a person who has demonstrated their ability to identify hazards and problems Qualified person: a person who has extensive knowledge and expertise who can solve complex problems Source: Rigid Lifelines
Some manufacturers have both light duty and heavy duty versions of each truss. Always be sure to check with your manufacturer’s load charts before utilizing any truss as load charts are not interchangeable between manufacturers.
Truss Terminology
Knowing your terminology when working with truss is important. With everyone on the same page, telling your crew to sling the truss at the third panel point is a clear directive that makes for a more effortless rig. Communication always improves when everyone can be on the same page. When rigging truss in any fashion it’s critical to not only look and sound like you know what you’re doing, but to also know what you’re doing.
Working with truss means you’ve got to know these terms—and just as important, you need to understand the size, make, and specs of the truss you’re using. You should also be familiar with the manufacturer’s guidelines and the engineer’s load limits for that specific truss. Here’s some terminology.
Chords
Maintain the stability of the diagonals and transfer vertical forces
Truss ladder
The diagonal, horizontal, and vertical members that make up the truss side face
Diagonal
Transfer vertical forces horizontally to the chords
Panel Points / Nodes
The points where diagonal, horizontal and vertical members are welded to the chords. Engineered to be the strongest parts of the truss.
Horizontal Spreader
Connect the chords horizontally
Vertical spreader
Connect the chords vertically
Internal diagonal
Not integral to the truss load bearing, they just help maintain the truss shape during construction
Bolt plate connection
Uses 4 grade 8 truss bolts, nuts & washers for connections
Forkend connection
Uses clevis pins & clips for connections
Spigoted connected
Uses spigot couplers, clevis pins & clips for connections
What are the different types?
Box truss comes in a variety of shapes and sizes, and the type you use largely depends on your application and even your region. In the film world, we’re almost always working with standard 4-chord box truss because it offers a solid balance of strength and portability. But even within standard 4-chord truss, you’ll find differences—not in the structure itself, but in how the sections connect.
Bolt plate
Bolted truss uses four grade 8 truss bolts with washers and nuts to secure the connection at the gusset plates. Bolt plate truss is most common in the United States film industry because of its legacy use, higher structural demands, and industry standardization.
Bolt Plate
Protective Bolt Plate
Fork End
Forks mate at each end of the truss chords and are secured with hitch pins and clips. More popular across European markets for theatrical rigging, touring stages, and TV studio installations.
Steel Forkend
Aluminum Forkend
Spigoted
This box truss system uses conical connectors that fit into the ends of the truss tubes along with pins and safety clips to secure the connection. This type of truss dominates live events, concerts, and European film markets because it’s faster, more modular, and easier to tour with.
Spigot spacers are used for connecting truss lengths together
Spigots come in a variety of variations and can be used to modify the length and connection points of your truss
Do not use an impact driver to tighten truss bolts! They can be over-tightened, potentially damaging the threads or breaking the bolts.
What are the different sizes?
Box truss comes in sectional lengths that may be attached together through their connection points. It is possible to create longer spans and different shapes by joining truss together. Rental houses usually carry a multitude of lengths and a number of sizes. The most common lengths are 1’, 5’, 8’ and 10’. When joining truss together you typically stick with 1 type of truss and work off that. There are some adaptors that narrow down box truss from larger sizes to a smaller size, but we are generally sticking with a single size run unless we are doing super specific rigging.
Additionally, curved truss comes in a variety of sizes and diameters.
12”x12” Box Truss
Most common in film, live events, and small to medium structure builds. 12” box is what we’ll reach for when we want to build softboxes, hang lights on stage, build overhead flyswatters or lift-supported softboxes, and small to medium platforms.
20.5”x20.5” Box Truss
20.5” box truss steps up in both strength and load capacity. Heavy loads, larger spans, and bigger rigs. This truss size is commonly used for large softboxes, heavy hanging positions for lighting, truss off truss applications, and beefy platforms and structures that need to hold a ton of weight.
Curved Truss
Curved truss comes in both 12” and 20.5”. We’ll use curved truss to build curved backdrops and lighting positions, rig circle softboxes and conform to architectural / set piece contours.
We’ll sometimes mix both 12” and 20.5” truss in the same rig. It’s common when we’re hanging truss from other truss—20.5” dead-hung up top from the beams, with 12” truss hung off motors below the 20.5”. You’ll also see both sizes used in self-climbing tower setups, where the vertical towers are 12” and the sleeve blocks and spanned truss are 20.5”. (We’ll get into that more below.)
Truss Orientation
Box truss typically features horizontal cross members along the top and bottom chords, with the “truss ladder” (the diagonal bracing) running along the sides. It’s critical that truss is assembled so the diagonals in the truss ladder form a continuous pattern between connected sections. If the diagonals are misaligned, it compromises the structural integrity and voids the manufacturer’s load ratings. A truss’s load data is only valid when the truss is oriented in its intended upright position.
On some truss designs, you’ll notice a mix of narrow and wide horizontal spreaders. In these cases, the face with the wider horizontal spreaders is designed to face downward when the truss is hung or supported—this side is engineered to handle compression under load and the spreaders are designed to support hanging lights.
It’s important to understand that hanging or using truss “on its side” significantly changes its load-bearing characteristics. Truss is engineered to work with its chords in compression and tension, with the truss ladder distributing forces across the structure. When placed sideways, those lateral ladders provide no structural benefit to vertical loading, and the truss’s ability to safely handle load is greatly reduced. Simply put: the manufacturer's load chart no longer applies when truss is used sideways.
How To Read Truss Load Ratings
This section comes with a big disclaimer: not all truss load tables are the same. Check with your specific truss manufacturer for an accurate load table specific to the truss that you are using. These charts are NOT interchangeable between manufacturers.
General rule of thumb: If the total weight of your load (no matter the location of the hanging point or points) is less than half of the total Uniform Distributed Load (UDL) for your span, you won’t be over stressing the truss.
Learning how to read load tables is a vital skill when working with box truss. When working with truss for any type of overhead rigging or structures that could fail and hurt someone, you want to be a qualified person. Walk into any truss rig with the confidence of safety. Manufacturers provide truss-loading data charts that breakdown detailed information relative to truss type, truss span, and load type. A lot of truss load tables use similar terms. You’ll see a list of spans on the lefthand column with more columns to the right for uniformly distributed loads, center point loads, third point loads, quarter point loads, and fifth point loads. Listed in each of the right hand columns are the load weights and the maximum allowable deflection. All load chart data references a simple span - meaning distance between two end supports.
Uniformly distributed load: A load that is distributed evenly along the entire span of the truss such as a continuous row of lights or a translight.
Center point load: A single concentrated load placed exactly in the center of the span
Third point load: A load that is split into 2 equal loads evenly spaced at each third point along a span
Quarter point load: A load that is split into 3 equal loads evenly spaced at each quarter point along a span
Fifth point load: A load that is split into 4 equal loads evenly spaced at each fifth point along a span
Example: Let’s break down this load chart. A 20’ span of this Tomcat light duty 12”x12” plated truss would be able to support a 1,261 lb center point load. Deflection would be 0.52 inches. The uniformly distributed load for the same span would be 126 lbs per foot with a total load of 2,520 lbs.
Keep in mind that load charts assume proper truss orientation. Flipping a run of truss on its side, not properly joining truss together to continue the ladder truss pattern, or side loading voids the chart’s data. Also remember: these charts apply to static loads. If your load is in motion—like a camera traveling along a run—you have to account for dynamic loading, not just static weight. That means dialing in more specific load calculations to handle the extra force on the truss. Shock loads are a more extreme case of dynamic loads. The key? Knowing how fast things are accelerating or decelerating, because that’s what drives the increase in dynamic force.
Bottom line: Never guess load capacity. Always verify with the specific truss load chart for the brand, model, and configuration you’re using.
When cantilevering truss, your load needs to be less than the CPL for a span 4 times the cantilever’s length.
Hanging Box Truss
When hanging box truss it’s important to know that truss has been designed to carry loads at specific points - known as panel points. These are the points where the main chords intersect with the diagonal and horizontal members. These nodes are engineered to be the strongest parts of the truss because they’re where the forces are evenly transferred throughout the structure. You can lift truss a few ways:
Truss lifting brackets
Rigging plates
Slings
We typically use round slings to hang our truss in the film industry.
Whenever you hang truss with round slings - whether you’re using GAC Flex or Spansets - it’s essential that the sling is wrapped around these panel points. When loads are applied at a panel point the forces distribute horizontally from diagonal to diagonal. This preserves the truss’s intended system of tension and compression, allowing the forces to travel through the diagonals and chords without introducing unintended stresses.
A truss pick in between panel points, or mid chord, could cause flexing, bending, or even buckling under load. The truss’s load capacity is highest where it can evenly distribute forces between components and isn’t optimized for mid chord picks.
Slings
Round slings are used to wrap truss for pick points. They are flexible, soft, and non-abrasive. There are two basic types of round slings: synthetic polyester core and wire rope core. Both types of slings contain an endless core loop covered with a protective fabric outer layer. Wire rope core slings aren’t as flexible as polyester core slings, but they’re stronger and are resistant to heat damage. Just keep in mind, both types can be affected by water exposure. Standard sling lengths are 18”, 3’, 6, 9, and 12’.
Spansets: Synthetic core slings made from 100% polyester fibers, looped continuously to form a strong inner core. This core is encased in a protective fabric sleeve to guard against damage and wear.
GAC Flex: Constructed out of Galvanized Aircraft Cable, GAC Flex are wound in an endless configuration that form an Independent Wire Rope Core. They are similarly covered with an outer polyester layer for protection.
Color-coding identifies the sling and its load rating in various configurations but in the film industry we only use black sling jackets. Just like with box truss, slings have load capacity charts that are specific to each manufacturer. The charts will give you a breakdown of all the different color slings and their specs, but for our use we can just check the tags on the slings themselves since we only use black. In addition, you can find the load rating data on the sling tag which will show you the various ratings for the different sling configurations (Basket, Choker, Vertical). Always be sure to check the load ratings and identify the WLL (Working Load Limit) for the particular slings you are using. These numbers, like truss, are manufacturer-specific and are not ubiquitous across all round slings.
Steel safeties are run from the hoist hook, through the truss, to the other hoist hooks. They are meant to provide a safety for the truss in the event of a synthetic round sling (spanset) failure due to heat or fire. Steel Flex (GAC Flex) was created to mitigate this problem. For this reason, GAC Flex usually does not require a back up steel safety because they are already made of steel. In the United States, this decision is determined at the discretion of the sound stage, production company, or fire marshal.
Rigging Method & Setup
If we’re hanging truss with slings, what are the best practices to follow? Here are a few important things to keep in mind when using round slings for the job:
Attach at your panel points
The basket hitch is the strongest hitch because two legs support the load
Don’t side load your truss
Wrap the chords evenly for proper support and to prevent rotation
Never wrap the sling on a connection point or a piece of hardware
For 12” box truss we’ll often use 1 sling to wrap the whole piece. When we do this we’ll sling in a basket configuration. Feed the sling underneath the truss and wrap the chords. You can either wrap the bottom chords and the top chords, or wrap just the bottom chords or just wrap the top chords. In all cases, make sure you don’t wrap the top chords on one side and the bottom chords on the other; keep it consistent.
Choking the lower chords with 2 separate slings is often used for larger 20.5” box truss, but can also be used with smaller 12” box truss. Standard configuration for 20.5” is to use two 3’ or 6’ slings choked around the bottom chords, wrapped on the upper chords, and joined at the top with a shackle (we use 5/8” anchor shackles for truss). You can either wrap the top chords in this configuration (which can help shorten the slings if you need to) or you can keep them unwrapped. If you keep the top chords unwrapped then make sure to keep your slings on the outside of the truss - it helps with stability.
In all cases, the bridle angle at the slings’ apex shackle should never exceed 90 degrees. A higher angle puts too much stress on the sling as well as the truss upper chords.
When slinging truss with whichever method you choose, always make sure the sling’s tag with the manufacturer’s information and specs is free and visible. The fire marshall may want to inspect tags so it’s always good practice to keep them unobstructed and visible. They are normally placed on a straight run of round sling right below the connection point at the top shackle.
Pre-Rigging Safety Checklist
Before flying any truss or loading a structure, run through this checklist:
✅ Confirm proper truss orientation (upright, not on its side).
✅ Verify that all truss sections are correctly connected and aligned (continuous ladder pattern).
✅ Check manufacturer-specific load charts for the exact truss type and size you’re using.
✅ Confirm all slings have visible, intact tags and that WLL ratings exceed the load.
✅ Attach slings only at panel points; avoid mid-chord or unsupported picks.
✅ Check sling wrapping method (basket or choke) is applied consistently.
✅ Ensure bolts or pins are properly torqued and secured (not over-tightened).
✅ Review if dynamic loads (moving cameras, shifting weights) are involved; apply proper safety factors or consult engineering.
✅ Keep a backup safety system (like steel safeties) when using synthetic slings where required.
✅ Conduct a visual inspection as a competent person before lifting.
Common Mistakes to Avoid
Even seasoned grips can slip up in ways that compromise safety or slow things down. We’ve covered a lot of best practices—so here’s a quick recap of common pitfalls to avoid. Keep an eye out for these:
❌ Picking mid-span instead of at panel points. Weakens load distribution and risks bending or collapse.
❌ Mismatched truss sections or mixed manufacturers. Load charts are manufacturer-specific; never assume compatibility.
❌ Using worn, untagged, or uncertified slings. Always check the tag, working load limit (WLL), and condition.
❌ Over-tightening bolts with an impact driver. Can damage threads or break bolts; use hand tools and torque as recommended.
❌ Incorrect sling wrapping. Top chord on one side, bottom on the other introduces unwanted rotation; always stay consistent.
❌ Ignoring dynamic load effects. Moving loads (like camera sliders or traveling rigs) increase forces; factor them in or consult an engineer.
Box Truss Accessories
Box truss accessories expand your build options. Here are common components you’ll encounter:
Applications and Uses in the Film Industry
Hanging Positions for Lights
When lights need to be hung, box truss is a great solution. It offers greater strength and rigidity than speedrail, allowing fixtures to be hung more securely while spanning longer distances between pick points with less deflection. When rigging truss on stage, chain motors are typically used for lifting and positioning the truss—providing a faster, safer, and more efficient way to fly lights. You most definitely do not want to use pulleys when lifting long sections of truss.
Rig by Legacy Grip, gear from C&C Studio Services
Self Climbing Towers
Self-climbing towers are ground-supported systems that raise truss into the air. ****They use vertical 12”x12” box truss as the tower structure, with 20.5”x20.5” box truss spanning horizontally between towers. To lift a spanned truss, you’ll need at least two towers—though you can also create a full grid or a movable overhead diffusion frame by placing towers in all four corners.
The system works using sleeve blocks (which slide over the vertical truss), a head block at the top of each tower, and a chain motor that runs up and over the head block. The chain motor attaches to the spanned truss, allowing the structure to lift itself as the motor pulls the chain. Perfect for “goalposting” lights outside house windows or raising up a temporary grid in a large house interior.
Rig by Luke Poole, gear from CSC
Telehandler Frames
Truss swatters are built when we need more rigidity, especially in light winds, or when a telehandler is required in place of a condor due to terrain limitations. Overhead truss frames are commonly configured as either diffusion or negative fill. You can also fly a dutchman off one of the sides to extend your coverage. Vertical truss frames work well as VFX frames for either blue or green screen.
Rig by Legacy Grip, gear from Show Rig
Softboxes
Truss makes large-scale softbox builds possible, offering the rigidity and support that speedrail alone can’t achieve. We typically construct the top frame out of truss, incorporating ribs to integrate lighting fixtures directly into the build. Speedrail is then used to complete the bottom of the softbox, creating the necessary distance between the lights and the diffusion rag for even, controlled illumination.
Softbox rig and gear by Carlos Boiles at CSC
Tenting
Large-scale outdoor tents use box truss for the strength and durability needed to withstand weather conditions. A truss-based tent structure allows for larger builds with extended spans capable of supporting bigger rags. These structures can be ground-supported with box truss or flown overhead using a telehandler frame. An added advantage of truss tents is their ability to support lighting—they provide already integrated rigging points to hang fixtures and offer more flexibility for varied light placement if you need it.
Rig by Grip Nation Rigging, gear from Grip Nation Rigging
Platforms
Need to level a 75’ Supertechno on a sloped street? Or place a crane on the side of a hill? You’re going to need a truss platform. Truss platforms create level, stable ground where it wouldn’t otherwise exist. They can also elevate you above the ground or over sets on stage. Use them to build access points for tall sets with integrated stairs, or to lift gear up using a crane or chain motors. Your only challenge is figuring out how to get the truss halfway up the mountain…
Rig by Grip Nation Rigging
Camera Rigs
Box truss camera rigs are the answer when you need a build that packs a punch. Truss lets you go bigger, supporting ambitious designs like large-scale rainbow rigs or oversized lazy susans. Just be warned—when working with large truss rigs that require counterbalance, you’re going to need a lot of it.
Rig by Legacy Grip, gear from C&C Studio Services
Temporary Structures
Temporary truss structures come in all shapes and sizes—and that’s the beauty of them. Use truss to build foundations for set pieces, integrate camera positions directly into set builds, or create structures to hang lights and video walls. With temporary truss structures, your only limits are your creativity (and maybe your budget).
Rig by Grip Nation Rigging
LED Walls
LED walls are heavy—really heavy—which is why truss is almost always part of the build. Truss provides the strength and stability needed to safely hang or ground-support LED video walls, making the entire process easier, safer, and one of the best solutions. You’re not using speedrail for this stuff, that’s for sure.
Rig by Grip Nation Rigging
Crane Supported Overhead Frames
Large overhead frames—like 60x60s—need to be able to withstand some wind and maintain structure with minimal deflection. In these situations, we turn to truss for its strength and rigidity. Typically, we’ll use 20.5” box ****truss when building large frames without interior rib support, as it provides the structural integrity needed over wider uninterrupted spans. For smaller frames, or when we can incorporate internal ribs to spread the load, 12” box truss is often the preferred choice.
Rig by Jason Selsor, gear from Stage13 Rigging Rentals
Whether you’re building massive softboxes, supporting LED walls, or lifting complex rigs, box truss gives grips a scalable, modular foundation. Mastering its use opens up a world of creative rigging possibilities.
Manufacturers
When it comes to truss, there are a few key manufacturers that stand out against the competition: XSF, Tomcat, Global Truss, and Tyler Truss. Each has its own lineup of gear, connection styles, and accessories, but at the end of the day, they all deliver solid, dependable products that hold up on set. Some rigs might call for one brand over another depending on what you’re building, but if you stick with these names, you know you’re working with trusted gear that’s built for the demands of film and live events.
Bringing It All Together
Box truss is so much more than just a way to hang lights — it’s a versatile, modular backbone for some of the most creative and ambitious rigs grips build on set. Whether you’re flying massive softboxes, spanning a self-climbing tower, supporting an LED wall, or building an elevated platform, understanding the fundamentals of truss — from its load capacities and connection types to proper sling methods and best practices — is essential for working safely and efficiently.
As grips, we pride ourselves on knowing the right tools and techniques for the job. Mastering box truss doesn’t just improve the strength of your rigs — it elevates your problem-solving, boosts crew confidence, and helps bring complex production setups to life. Keep this guide bookmarked, stay sharp on load charts, and remember: a well-rigged setup isn’t just about strength — it’s about smart, informed choices that keep everyone safe and the the schedule moving.
by:
Legacy Grip
