When building a race car, one of the most frustrating and misunderstood parts of the build can be the roll cage. I could easily write an article five times this size when it comes to explaining how roll cages work in a variety of ETs and car configurations. I am going to explain the key rules and requirements on building a 10 point, or 8. Meaning if your vehicle is going to run low 10s, but then might see the 9s sometime, building the faster cage in the car will lead to less headaches down the road.
Our power will come from a Dart block-and head-equipped ci small block Ford that features an AED blow thru carburetor and a Paxton NOVI supercharger to produce in the neighborhood of 1, horsepower. This is going to be achieved through a Crower hydraulic roller valvetrain and a moderate amount of boost. This will allow us to drive the Mustang around town when we want, then throw the slicks in the trunk and head to the dragstrip.
The best part of the Mustang was its very clean interior and it needs to stay clean. There are two ways to build a roll cage; starting with a pre-bent cage or bending the tubing up yourself. If you have a popular vehicle, there is a good chance Chassisworks already makes a pre-bent cage for it. The tubing size requirement on 8. Also, while a chromoly cage is typically lighter due to its lower minimum wall thickness, it can only be TIG welded, while mild steel can be TIG or MIG welded, though the welds need to be clean, complete without holes, and show no signs of grinding.
Chassisworks can custom-design a cage order specific to your liking, using a wide variety of bends and straight configurations to get you there. In addition to the roll cage, we also opted for a pair of swing out door bars to make getting in and out of the car easier, as well as subframe connectors with X-brace from sister company Total Control Products. The complete Chris Alston's Chassisworks roll cage, swing-out door bars, and window net kit.
Nothing screams speed like a 60 horsepower Mustang with a point roll cage in it. When it comes to preparing to install a roll cage, you will want to remove everything from inside the car that you can. This includes carpet, seats, and door panels. If you have a headliner that needs replaced and want to keep one in the car with the cage, replace it beforehand to save yourself a big headache.
How To Build A Roll Cage – Everything You Need To Know
We will go through the steps later when it comes to protecting the headliner during the final welding. The pre-bent cages are purposefully made long to accommodate for variances in vehicle builds. Also, tack weld the entire cage in place before completely welding it to ensure a better fit.
Additionally, whatever seat and seat mounts you plan to use for the vehicle should be installed.Link Suspension Design for Off Roading
The driver, or someone of similar build, should be present for the variety of clearance checks. We took the Mustang to local racing shop Mckinney Motorsports to have the cage installed.
Floor Support Plates. The Chassisworks roll cage kit comes complete with pre-cut 6-inch x 6-inch plates for your floor mounting.
Welding the plates to the car does not require the use of bottom plates but must be completely welded to the floor.The safety of the drivers and passengers should not be forgotten when building up your dream rig.
The need for a roll cage is both an after thought and a piece of the master plan from the beginning. With Project Storm Trooper its current status and future additions, the need to build a roll cage is necessary. Fabrication is a skill that some people have and others lack. For us, we know the ins-and-outs, but are always up for some extra guidance. As with any good project, it always best to start with a clean slate.
We removed the dash and skinned the inside of the cab. We headed over to RSO Performance in San Jacinto, California to see how they build their roll cages and to pick up some pointers on ours. RSO has been using a program called Bend-Tech to help design roll cages and bumpers for their vehicles. We highly recommend the program for anyone from the DIYer to the professionals. We will be adding to it as we progress through the cage. We were excited to see what our roll cage would look like before we started fabricating the first tube.
The program allowed us to input our die measurements to make sure the bends would match. Our roll cage would be done in stages, allowing us to update the measurements in Bend-Tech if something changed in the installation. No problem! Bend-Tech allows you print out notch templates to make sure that the tubes fit the first time, every time. Once the measurements are plugged in Bend-Tech does the rest of the work.
It will calculate the angles, where to start the bends, and even give you notch templates. Bend-Tech not only gives you the exact bend measurement it also shows you what it will look like as you are bending it through your die. Any twists can be seen before going and attempting them. The first tubes that we wanted to get installed would run from the frame up the A-pillar and out the back of the cab.
These tubes would be the foundation for the rest of the cage. Once those were in, we would add the dash bar and move our way to the back of the truck. Using the program first hand on both the design and installation side we can say that it did make our lives a lot easier and less stressful.
Knowing exactly how long of a tube to cut and how the notch would land made sure we would waste as little of material as possible. The roll cage in Project Storm Trooper is starting to take shape. Everything will be built off of the long A-pillar bars. Stay tuned for more updates as we finish building out roll cage!Our candidate for a custom Roll Cage is a Mustang.
The custom Ford 9 inch will have 35 spline floating axles. This project is from Australia so we aptly named it the "Out Back Fastback ". We start by figuring the angles at strategic locations up and around the roof area and we make note of our findings on paper to come up with a plan. Using a flexible protractor makes a major difference by taking the guess work out of it.
Regardless if you are using chromoly tubing or mild steel, all the techniques are the same, only the bend back rates change. Lou marks his tubing according to his plan and away we go.
We always leave the tubes a minimum 6 inches longer to allow for exact trimming and or notching when joining to another bar in the cage. We have a JD Square model 4 bender but any hydraulic bender will do the job as long as you have the correct radius for the project requirement. As seen on the end of the tube he has a level attached with a clamp to the pipe which assures an accurate bend when looking to do multiples of the same bend.
Degrees are on the dial as with most benders. We start at 0 and bend just a bit past 30 degrees allowing for " Bend Back ". The pipe is now flipped over on this bend because of the angle needed to clear components. As seen the bubble is still level. We will now make our 60 degree bend and fit it to the car. Different angles are needed to clear components so the dial allows duplication on the opposite side of the car.
Simply write down the numbers and repeat on the opposite side. Once we were satisfied with the fit we simply made a duplicate for the other side.
As mentioned we now have excess tube where we can cut and trim away to be sure of a dead on fit. In order to fit the tube we have to notch the end to fit against the main hoop as seen. We use a wire form tool to tell us the exact angled notch we need to match the tube. Another view to show it lining up close to the windshield post and then stepping down through the dash corner. Then we made them in 14 gauge steel. Tucked up close and just enough room to clear everything but still remove the kick panel.
Maximum foot room is needed. A cross bar from one side to the other of the main hoop is mandatory and a minimum requirement in most rule books. We will build a complete X in ours for added strength. Next we prep some of the bars to accept bolt on sleeves that we machined. This Roll Bar will be removable for street use and also help in cosmetics for paint and assembly.A main hoop is the foundation for any roll cage build and it is crucial that the fabrication be done with expert craftsmanship if it is to be used for any type of racing environment.
Did you use this instructable in your classroom? Add a Teacher Note to share how you incorporated it into your lesson. The vehicle interior should be completely removed of all components leaving only painted metal surfaces. Welding will take place within cab of vehicle and sparks will damage interior parts, and wiring.
Note: Removing the interior is different for all makes and models and comes with its own challenges. Interior removal will not be covered in these instructions.
Building A Roll Cage With The Help Of Today’s Technology
The main hoop should be located directly above the drivers head or just behind the head of the driver. It could also be placed adjacent the B-pillar of the vehicle. Two height measurements will be taken, both of the points measured will be needed for the width measurements.
Using 36" masking paper, cut two strips as long as the car is wide. Lay them side by side and tape the together carefully, this is will be used to mark out a template for the main hoop. Using a felt tip marker and a straight edge long piece of scrap steel draw a line datum line two inches up the masking paper parallel to the edge.
This will represent you datum plane, place a mark at the center of the line. The mark will be used to create a center line later. Measure up and mark height 1 on both sides of the masking paper. Draw a line connecting both marks Line should run parallel to the datum line Repeat this same process for height 2.
Divide width 3 by two which will give the center of width 3. Align the center of width 3 with the center mark of the datum line and place a mark at zero and at width 3. Using a large framing square and and a straight edge, place the framing square on the center mark of the datum line, lay the straight edge up against the framing square so it is perpendicular to all the lines already on the template.
Place a mark on the line for height number one, do not draw the center line. Measure diagonally from the mark on height 1 to the marks made from width 3.
These measurements should be equal, if not adjust the mark on height 1 so that they are equal. Draw the center line. Divide width 1 by two to find it's center. Align the center of width 1 with the center line at height 1 and mark at zero and at width 1 Repeat process for width 2 at height 2 and mark. Using a straight edge connect the marks on the left side of the center line, and repeat for the right side of the template.
These lines will represent the outer perimeter of the main hoop. Measure the angle of each corner created using a protractor and write them next to their respective corners. Be sure the die makes contact with each line made without going crossing the line and draw the curve. This mark will be transferred to the tube later and is known as the offset mark. Repeat for the other corner at height 1 For the bends and height 2 follow the same process but the marks will be made on the line going up to height 1.
Now that the template is complete measure the outer perimeter of the template and add a foot to this measurement. This will give the total length of tubing needed to create the main hoop. A mechanical mandrel tubing bender will be used to create the bends in the tubing. A mechanical mandrel tubing bender is a metal fabrication tool that can bend tubing up to degrees.
This tool is operated by hand using the principles of leverage to bend round tube incrementally. A long lever is attached to a ratchet and every time the lever is pulled the tube bends about five to ten degrees.
The lever is placed back in its original position and the ratchet is placed in the next notch to allow for another five to ten degrees of bending. This is repeated until the desired angle is achieved.A roll cage is a metal framework that can be built around the inside of a vehicle. They are typically used to reinforce the vehicle and ensure that the passenger is protected in the event of an accident, particularly if the car rolls.
Roll cages are predominantly used in cars that are being used for racing and stunt work because of the aggressive driving style and the increased danger. For this reason, they are also often used in off-road vehicles. An everyday vehicle is unlikely to have or need a roll cage, but sometimes a roll bar is installed to give the driver some amount of protection in the event of a rollover.
There are a number of roll cage designs that exist for use depending on your needs. An 8-point roll cage is the most basic and therefore probably the best option if this is your first build. An 8-point roll cage includes a main hoop, a windshield brace across the roof, a back brace, sides, subframe struts, and gussets. Beyond this, there are 10, 12, and point designs that provide more structural integrity. Everything you need to know to clear that out is in there. However, steel is heavy and will hinder your performance to a degree if you are using the car for racing.
Therefore, a viable alternative to steel is chromoly.
Before you start building, you need to make sure you have enough room to install the roll cage. You may need to remove the car seats and carpet. Another tip before you start building your cage would be to make sure that you have enough room to install it. Measuring properly is crucial for a successful build. As we said previously, measuring is absolutely crucial to your build.
These are the measurements that we recommend taking. This is where the roof bar of the roll cage will go, so you need to make sure that there is space for that bar, and space for it to start bending down. Therefore, it is necessary to measure the angle at which your roof meets the side of your car so that you can determine the angle that the tube will need to bend.
This refers to the height of the car from the floor to the roof, this determines how high the roll cage needs to be. This refers to the width of the car from side to side. This determines how wide the hoop can be. Ensure that there are no obstructions that could get in the way of the sides of the main hoop though as they should go all the way to the floor.
If there are obstructions, measure from those instead. This refers to the distance between where you intend the roof bar to end and the sidebar to begin. This measurement will determine the length of your bend that connects them. Floor, in this instance, refers to where the base plate will go for the brace. The main hoop in this instance refers to the part of the main hoop that the brace will attach to.
Fabricate a Main Hoop for a Roll Cage
In order to measure this, there are a few steps you must take. First, get the horizontal distance between where the brace will go in the base plate and the hoop. Secondly, get the vertical distance between the base plate and where the brace will attach to the main hoop. By using these two measurements, you can find out the length of the tube you will need to go diagonally from the main hoop to the baseplate. This refers to the horizontal distance between the side tubing on the main hoop.
The seat crossmember goes in between these two bars. Base plates are what you will use for attaching the roll cage to the floor of your vehicle. The usual recommendation is 3mm thickness, however, you can use thicker plates to provide more stability. When determining where to position the plates, the plates attached to the door braces should be next to the firewall and the plates attached to the rear braces should be placed behind the front seats.
The main rule to follow when bending your tubes is that there should be no signs of deformation and the bend should be totally smooth.If you go to the drag strip enough, you are almost certainly going to get bitten by the speed bug sooner or later.
And as we all know, once you are bitten, the need to go ever faster never leaves you. That means eventually the tech man is going to wave you down and let you know that until you show up with a roll cage in your car, you aren't getting back on the track again. With that in mind, we thought we'd share some tips on building a better roll cage. These should help whether you are building your own cage, or shopping for a fabricator to help you out.
Cline is well known for his scratch-built Pro Mod race cars, but he also regularly turns out everything from the pro class cars all the way to bracket cars for budget-minded racers. We've been documenting the progress of a Mustang Cline is building for a client, and along the way he's given us a ton of great information that is useful whether you are planning to build your own cage or looking to determine if a fab shop is capable of building a cage to the highest standards.
Check out these tips and get busy building your own cage! This particular Mustang is being built to meet SFI standard The SFI Foundation has guidelines for a wide variety of different car types and speeds.
Practically all tracks follow the SFI certs, so following their guidelines is the best way to be sure you can get on track no matter where you go. The SFI guidelines don't prescribe every single bar placement, so there is still room for personalizing your cage.
What it does is give you a plan for where particular bars must be, as well as their size and wall thickness. To access the plans, go to www. Whatever you do, don't go building your cage off of a plan your buddy sketched on the back of a napkin. It will only cause you heartburn down the line. It is relatively easy to upgrade an engine or suspension as you go.
The roll cage? Not so much. As you can see from the photos, building a roll cage typically requires stripping a car to its bones. That's why Cline recommends making a plan before any build begins and fabricating the roll cage to match your end game.
Because going back in can get expensive. One area where Cline says it is easy to make upgrades to the cage is if you build a "subframe" underneath the car more on this later than simply welding the cage to the car or using square tubing to build frame rails in a unibody car. No cutting on the car and very little cost. The usual course of action when building a cage in a unibody car is to create attachment points for the cage either by welding in square tubing to create frame rails or metal plates against the sheetmetal.
This creates secure anchor points for the cage so it won't rip out as soon as the car takes a hit. But a third option is to build a subframe for the cage underneath the car. Besides making for easier upgrades as Cline mentioned earlier, this also creates a degree protective halo around the driver, provides for excellent structural integrity, and makes creating seat mounts a simple process.
Cline builds the frame—basically a simple square that's gusseted for strength and the same width as the roll cage up top—tight to the bottom of the car, but only tack welds it into place. Then, when the major components of the cage are fitted in the driver's compartment are complete, the tack welds are cut away. This allows the cage to drop in place a few inches so that the top of the bars can be securely welded without the roof of the car or the windshield getting in the way.
The difference is that a wire-fed MIG weld can be used to hide a multitude of sins—namely, poor cage fitment. Cline says the biggest determining factor in the price of a car isn't chromoly versus mild steel, it's whether you choose MIG or TIG welding. TIG welding is so much slower and labor intensive versus MIG that the extra labor charge can significantly add to the cost of a car.
If you can afford to have the cage TIG'ed, it only makes sense to go ahead and upgrade to chromoly. But you have to use larger sticks of tubing or more wall thickness, and it costs you weight. Plus, if you ever try to sell your car a mild steel car isn't going to bring as much. It really all comes down to weight, and we all know weight costs you speed.To build a roll cage from scratch, you've got to have the right tools to do the job.
The reason for this is that during a technical inspection or safety inspection, the inspector or track official is going to look at the roll cage to determine that it is indeed safe to use.
If the cage does not pass the inspection, you will not be allowed on the track. Roll cage fabrication requires bending, cutting, drilling and welding tools, and cannot be accomplished without them.
Welding tools are used to join the bars of the roll cage together. Each form of welding results in the same final product, with the differences being in how the final product is accomplished. MIG is the most typically used and generally least expensive type of welding. TIG uses tungsten as a weld filler material.
Gas welding is the process of using torches to weld without the benefit of electricity. The most commonly used welding type for home applications is flux-core welding, which has the shielding gas suspended in solid form within the welding wire.
Metal band saws are used to cut the roll bar's individual pieces to the necessary length. They produce a straight cut, meaning that you'll have to use a tubing notch tool if you are joining the end of one roll bar tube to the midsection of another roll bar tube. The band saws that are most commonly used for roll cage fabrication are set up like chop saws. For example, rather than the tube being pushed against a fixed blade, the blade is fitted to a hinged fixture.
With the tube secured in one place, you use a handle to draw the blade down onto the tube, cutting it. Tubing notch tools are fixtures that use a typical electric drill and a metal hole saw to cut round notches in the ends of tubing. This allows you to perfectly fit the end of one tube together with the middle section of a second tube for a much stronger and more attractive welded connection point. To use the fixture, you place a hole saw into the chuck of an electric drill and then secure it to the fixture.
The end of the tube is clamped in place on the fixture and then the drill is lowered by means of a lever to cut into the end of the metal tube. Tubing benders work by applying pressure to a die that is the same size as the tube being bent. When the pressure is applied, the die forces the tube to bend.
These tools typically use gauges you can read while you are applying pressure to the hydraulic ram that does the actual work. This allows you to create the perfect bend in any size roll cage steel bar.
The importance of bending the roll cage bars rather than cutting and welding them is that round structures are stronger than straight structures. It is for this reason you see so many roll cages in race cars with round edges, rather than straight. This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information.
To submit your questions or ideas, or to simply learn more about It Still Works, contact us. Tubing Notch Tool Tubing notch tools are fixtures that use a typical electric drill and a metal hole saw to cut round notches in the ends of tubing. Tubing Benders Tubing benders work by applying pressure to a die that is the same size as the tube being bent.
About the Author This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information.