Harry Wagner
Contributor
When we add most modifications to our rigs, we can’t wait to go out and test them. A rollcage is the exception. It is a component that we hope we never need—but when you need one, you want to be very confident in its abilities. And just as apples can vary from Red Delicious to Granny Smith, not all rollcages are created equal. Materials, welding techniques, design, and mounting all play a part in the overall safety of the cage.
Materials
Cage materials typically include hot rolled electrically welded (HREW) steel, drawn over mandrel (DOM) steel, and chromoly DOM steel. In respective order, they increase in strength but also increase in price. In our opinion, DOM offers the best bang for the buck, with chromoly typically reserved for racing applications where the additional strength allows for lighter, thinner material to be used. If you have to use pipe on your rig, save it for your rock sliders.
Design
When designing a cage you must strike a balance between strength and packaging. Even the best cage is worthless if you can’t get into your rig to drive it. Triangulation is an important feature to add strength, as the shape is inherently stronger than a square at absorbing loads from various directions. Try to break up large, unsupported areas (like the roof area above the occupants) with gussets and diagonal bars wherever possible to ensure that the cage does not flex or fold under a hard impact to a corner.
Welding
Steel can be stick welded, MIG welded, or TIG welded. MIG welding is the most common and a great balance between strength, aesthetics, and time. TIG welding will give your cage that race car look but adds considerable time and expense to the welding process, and using the proper filler rod is critical.
Another factor that is important regardless of the welding technique but critical for TIG welding is tight-fitting joints where the tubes come together. This is analogous to doing proper prep work for a paint job -- it is time consuming but is often the most important step.
Mounting
Even the best cage isn’t worth a lick if it parts ways with your vehicle in a rollover. The best option is to mount the cage to the frame, either by welding it directly or using plates and bushings to isolate vibration. Mounting the cage to the frame also strengthens your chassis and makes it more rigid. If you can’t mount the cage to the frame, the next best option is to position the feet of the cage over the cab mounts. Use large foot plates (such as 6 inches square) with varying sizes on the top and bottom to resist just punching through the sheetmetal.
Bolt-In, Weld-In, or Custom. Which Is Best for You?
Many cage options are on the market, particularly if you have a popular vehicle like a Jeep Wrangler. The costs can vary widely both in terms of purchase price and installation. So how do you know which is best for you?
Bolt-In: Rock Hard 4x4 offers cages that clamp together inside of your Wrangler or Cherokee. They are inexpensive to ship and easy to assemble in your driveway, saving money. As a bonus they add rigidity to your unibody vehicle.
Weld-In: The next step up in strength is a weld-in cage, such as those from 4x Innovations for Toyotas and the Lazer Fit cages from Poison Spyder Customs for Wranglers. These show up on your doorstep prebent and notched for easy installation, and both companies offer some options for customization. Even if you hire a fabrication shop to install the cage, you will still save money with a kit when compared to custom fabrication.
Custom: If you have a vehicle with little aftermarket support, like a Nissan Pathfinder, custom fabrication is likely your only option. But even if you have a more common vehicle, a custom cage can be built to your specific needs. This will stand out from the crowd, but at an added price and downtime for installation when compared to a cage kit.
1. While a “pipe bender” may seem like an inexpensive solution, a quality tube bender is required if you plan to build your own rollcage. Pipe benders will kink tubing and significantly reduce the strength.
2. A tubing notcher is another useful tool when building a cage. Benders, welders, and notchers are not really cost-effective if you just plan to build one rollcage, but if you spread the cost out across multiple projects like bumpers, rock sliders, and the like, these tools can easily pay for themselves over time.
3. Tying the rollcage into the frame is worthwhile to ensure that the cage does not punch through the tub in a rollover. Here Nate’s Precision used a bushing and a plate to minimize vibration and allow the rollcage to be removed.
4. Tying the seats into the frame is another way to add safety to your rig. It is even possible to retain seat adjusters to allow for different drivers. If you mount the seats to the cage it is critical to also mount the harnesses to the cage in the event the cage separates from the vehicle in a violent rollover.
5. A crossbar behind the seats is useful not only to provide more strength to the cage but also allow provisions for harnesses to be mounted. Nate’s Precision properly positioned this bar just below the shoulders to firmly hold the passengers in place in the event of a rollover.
6. Gussets are available in a variety of shapes and sizes to add a personal touch to your cage. Gussets also provide more material and weld surface at junctions to increase strength.
7. Tubes can be used for gussets as well. Note that these are gussets, not grab handles. While the gussets can be used to aid in entry, if they were grabbed in a rollover it could result in loss of fingers.
8. Tungsten inert gas (TIG) welding is recommended with chromoly tubing due to the increased control in filler material and heat input. A variety of different filler rods is available and should be matched to the application to maximize strength.
9. The bigger the better when it comes to foot plates, to spread the load over a larger area. Also note that Samco Fabrication used Grade 8 hardware to secure this rollcage.
10. Fitment is important, particularly in an enclosed cab. Window rollers and emergency brake levers should still be accessible after the cage is added.
11. 4x Innovations offers prebent cage kits for Toyota pickups, Tacomas, and 4Runners. Each tube is labeled and notched to allow for easy assembly, providing a lot of bang for the buck.
12. It is critical to have tight junctions wherever tubes meet, regardless of the welding method or materials used. This is particularly important with TIG welding though, which uses minimal filler material.
13. Sleeving tubes can be useful for replacing sections of a cage without replacing the entire thing. Sleeves also allow for smaller, less complicated sections as well when building. Note the smaller tube slips inside the larger tube, and the tubes are butt welded and rosette welded for maximum strength.
14. Even the best design requires proper welding in order to be fully functional. Inside a closed cab the tubes can be tacked together, then the cage dropped down through the floor in order to fully weld the tubes together.
15. For our Ultimate Adventure project Super Dirty, Jesse Haines created a hybrid interior/exterior cage that maximized interior space while remaining more subtle than typical exocages. With few compromises we are seeing this style gain popularity around the country.
16. Tube clamps are useful to allow a cage to be removed from the cab of a vehicle, whether for final welding or if the cage must be removed at a future time. They also come in handy if you have a crossover bar between your shock hoops and over your engine.
