Building a Roll Bar, by Bob Elliott (3/04)
Here's some ideas on making a roll bar, and yes you can make your own.
If you’ve ever wished that your buggy had a roll bar and wondered how hard it might be to build one, I thought I’d share my recent experiences on fabricating my first. I’ve had a long time dream of building a Deserter GS ever since I was 18 or so, or a really long time ago. After finding an affordable, although very rough GS chassis that was structurally inadequate although pretty straight, I decided to take on a complete chassis rebuild and that includes the pretty uniquely shaped roll bar for this car.
The good news is that the only special tool required was the pipe bender. These are readily available from many places including Harbor Freight and will cost you about $100 to get it to your door. The one I used was a 10 ton version and it handled the 1 ¼ in pipe I sourced from a local railing company with ease. The pipe was 0.120 in. wall thickness and the OD measured around 1 5/8 of an inch, just about perfect for the look I was after. Oh, by the way, you’ll need about 12 feet of this stuff to make one simple hoop style roll bar with no extra cross bracing.
Just so you know, there is a difference between “pipe” and “tubing”. I’m no expert, but a pipe bender works fine on pipe and will just ruin tubing. It has to do with the OD or outside diameters not being the same, or something like that. Anyway, the pipe benders have the correct parts to fit “pipe” and “tubing” is different and will just kink. I’d guess that you’d need a tubing bender or something if you went that route.
Now, there are many reasons to have a roll bar and extra protection is only one, but if that is at least part of your goal, I’d recommend using something heavier than a muffler gauge of steel and stick with something substantial. Since I would be using paint on mine, raw steel was fine. Another good choice would be starting with stainless steel, but I have no idea where to get that.
After a couple practice bends on some scrap pieces, I noticed that the bender would leave two dimples on the outside of the bend where the two rollers made contact! Since that would ruin the whole look, I needed a solution. It turned out to be pretty easy one also. I cut out a section of 1 ¾ inch plastic pipe to protect the roll bar at the contact points with the rollers. (see photos for an idea). As it turned out, this worked perfectly.
While practicing on some scrap material, you’ll need to get a feel for how much extra bending you’ll need to apply. What I mean is that, the pipe I used had some spring in it and I had to over-bend it more than desired and it would spring back a bit. I have no idea if there is a simple rule of thumb for this or not, but if you go too far and over-bend a corner, I also found that the 2 inch receiver hitch would hold the pipe and with help, I could remove some of the bend.
What you really need to start with is a full scale pattern or model. Find some big pieces of cardboard, you can try a local appliance store and offer to take some of their trash away, I can’t imagine they would charge you for it. Cut it to the width to match the inside of your buggy. Find a height that works, preferably taller than your head and draw on the shape. Use a measure of some sort and try to be symmetrical. Now you could just bend in a couple of right angle 90 degree bends in each corner, but it will look homemade for sure. You actually need additional bends in each side for a proper tapered roll bar look.
The bottom of the roll bar side will be parallel along the sides of the body, somewhere above that you add in a small bend that give it a cleaner look.
This is a complete “How To” or step-by-step process, but more of a collection of things I learned along the way.
- Draw a template and mark the center of the roll bar on it.
- Mark every inch along the pipe as well as the center as a starting point.
- I’d place the marks on the welded seam.
- When you lay the pipe in the bender, keep the seam and your marks centered looking at you, i.e. not on the inside or outside of the bend. (see photo)
- Use the plastic bumpers to protect the pipe.
With everything in place find a good level floor and place the pipe in the bender and on top of the pattern. You’ll need some spacers to keep the pipe level to the floor at all times. (see photo)
Estimate the distance from the center to the first bend and crank away keeping track of the progress on your template. Go slow as you reach the goal, release pressure and reapply until you have the bend you want.
Now, check how close corner and the centerline of the pipe matches the template, this is your only chance to make any adjustments to get the second and most important bend in the right place. Make any adjustments necessary. If you were off a little, simply add or subtract the error from the center reference line so the next corner will be where you want it.
Always check to keep the pipe level to the ground and in the smaller bends on the side and hopefully when your done, you have something that matches the pattern. (see photo)
There are different ways to mount these, mine is integral to the chassis and welded, (see photo)
but on a fiberglass buggy, welding a plate to the bottom to drill and bolt to the floor-pan takes care of the bottom. On the sides, you can bolt this point here with muffler clamps. Be sure to use the largest washers or plates to prevent pull through in both the bottom sheet metal and the fiberglass sides. Also you could weld plates on the sides of the roll bar to bolt or attach it to the body.
On any glass buggy I’d suggest that you try to keep the shiny side up anyway, I’m not sure how well it would actually hold up in a roll-over, but it might the look your after.
Well hope this helps and just a note, I think it took me less time to actually bend the pipe than it did to write this article. I spent three hours in the garage and plenty more thinking about how to do it, before I actually did it. But I now have a nice solid roll bar that fits my car and me perfectly. All I can say is give it a try and good luck.
More photos on this and my GS build can be found at http://www.bimelliott.com