I build roll cages

[Chilezen]

Taco gussets!



I have built my own die to press the shape into the "taco" I need it to be. Then I use dimple-dies to create the recessed impression in the metal. I should take some pictures of those tools one day.





The gusset up here was made to compliment the aesthetics of the tacos in the Main Hoop bars. Looking at it from the front of the car head on, it makes sense.

This particular car is in a class that does not allow the cage to be welded to the car for added stiffness, so, windshield plates could not be added. I'll show you what those look like on other cars I've done.

[Red88]

Awesome thread

[Mike36]

Very cool! I really liked the roll bar you made for the convertible Vette.

[Chilezen]

Awesome thread

Thank you!

Very cool! I really liked the roll bar you made for the convertible Vette.

Thanks, but, I haven't made one for a convertible Vette.. What are you referring to? Perhaps you're thinking of a Targa Top? I've done those.

[Chilezen]

Alright, last few of the E30 cage, and then I'll move on to... a much newer BMW.








I just noticed I didn't take a photo of the intrusion bars.. oh well. They're there. Intrusion bars are the ones that go down by your feet, to protect.. your feet lol. They're optional, but recommended in most cases, just for added safety.

[Chilezen]

I'm not obligated to do this on behalf of my workplace, but I certainly owe it to my boss for allowing me to be happy building this stuff. With that said,

if you ever find yourself interested and needing a cage of your own, we sell this as a kit. With technology at our helm, I can run some bars through a few machines and mark and cut and bend each piece, and then put them on a pallet, and ship it anywhere around the country.

At this link, trackspecmotorsports.com you will find more detailed information if you wish to purchase this kit, or any of the others we've built. The kits are comprehensive, providing almost everything you need; all you need is a professional to install it!

Every cage kit purchased goes towards feeding and funding a young fabricator in need (me) and by funding, I mean helping me to build more car parts for E30's

I hope with this full series of builds I share, you see the details and care I put into my work. And if you have any ideas to share, please do! Any criticism and helpful comments are super appreciated, as I'm always learning and trying to improve.

[Chilezen]

Next up, an F87 M2 cage~





Lovingly simple, tightly fit, suits the car well.

[Chilezen]

This car received "bent X" door bars, which as you can see, are composed of an upper and lower bar with one bend each. They are welded together within the plates, where the apex's of the bends meet, and then the plates (I call them Bowties...) are welded over them, for both added strength and aesthetics. Sometimes I MIG them, this time I gave it a shot with TIG.

Don't know what MIG or TIG is? Okay, so look at the ends of every bar--where the bars are welded together, I used a process called MIG. This means that I use a "gun" that shoots out a metal wire and a special gas when I pull the trigger. The wire melts on contact when I am very close to where I want to weld, and the wire keeps coming out, and I move around the bar, creating the weld. This super-hot melting metal fuses the two bars together, and it leaves a "bead" behind, where the melted wire was. It was built up at the joint of the two bars.

TIG welding is similar in that I am melting metal, but the big difference is that I manually add metal wire, and the part that melts it isn't a gun, it's a torch, and that has a little needle-like end, which gets super hot. And instead of pressing a trigger, I use my foot to press a separate pedal, which turns on the torch. The more I press the pedal, the hotter the torch gets. I aim the torch at where I want to weld, then I add metal wire, and then I keep moving, adding and moving and adjusting the heat as necessary.

It takes more skill to TIG, and it takes way more time, which is why most cages are MIG'ed. Basically, MIG is like using a hot glue gun for metal. Squirt squirt and you're done lol.

[Mike36]

Thank you!



Thanks, but, I haven't made one for a convertible Vette.. What are you referring to? Perhaps you're thinking of a Targa Top? I've done those.

Ha, yeah I meant targa top.

[Chilezen]

Ha, yeah I meant targa top.

Oh sweet yeah, thank you. Those will be featured later. Btw, since usernames can differ between platforms, did you see the cages on my Instagram? What's your handle there, is it twinzmike?

[Chilezen]

Some cages can be too far from the inside of the car; there's too much of a gap between the bar and the car. In other cages, the bar is very close or touching. That's great, but only if the bar is fully welded all the way around. If the bar is too close to the car, and there isn't access to weld all the way around, it then fails at being a proper, safe cage. A bar that isn't fully welded is a weak point. There's no point in pushing a bar all the way to the edge to close the gap, if it isn't going to fulfill its purpose of being properly integrated with the rest of the cage.

All this to say, it's my job to get a bar as close to the inside of the car as possible, but still leave enough room to weld all the way around it. If you see a cage anyway or are looking to buy one from anywhere, make sure the builder can be in that middle-ground!

This picture represents how it is difficult to get a welding gun in there, but it is possible.
If the bar were any closer to the car, I'd have to cut some part of the car internally, or even externally, to fully weld it. Not worth it here.

Sadly, however, I have seen some poorly-built cages out there, on the racetrack, with shitty, poorly fit, poorly welded cages. And yes, they have passed inspections. Because the tech inspector is a horrible inspector. And the builder is a terrible builder. And the customer sadly doesn't know better, or at least they got what they paid for. Don't let that happen to you!

[Chilezen]

Gussets gussets gussets









I was pleasantly surprised I could re-use the taco gussets from the E30 in the diagonal/harness bar junction. Same angle and dimensions; win!

The dimpled plate that ties the main hoop to the B-pillar was first designed by cutting out paper/cardstock, and then transfering the design into the computer (by putting the paper in a scanner), and then refined, and cut into metal. I had to make 3 iterations because the paper was more flexible than the metal, so I got some unrealistic shapes in the paper that the metal couldn't conform to. But with enough bending/twisting, it worked! I have a video thing of the process.

[Chilezen]

I made a video

https://photos.app.goo.gl/R1FnMmrssDJKLyfM7

[ForcedFirebird]

As much as I advocate TIG, the welds on the tacos for the main hoop (MIG ones) are more pleasing to the eye. I've tried it many times, but thin sheet to the thick pipe just amplifies any irregularities in the beads. Your MIG skills are on point!

As far as weld access, I basically but the main hoop right against the B pillar and use weld sequence strategy to get 360°. Typically will drill the floor to drop the 4pt, then slide plates under after welding the tops, utilize the sunroof and tack/move as I go, then weld it to the car at the end.

So many ways to skin the proverbial cat, but you have some neat tools! Beats my tape measure and protractors lol.

[Chilezen]

In regards to the TIG'ing of sheet to tube, the material thicknesses are closely matched here; I use 14 gauge (0.078") plates on roughly 13 gauge (0.095") tubing. But yeah, welding to 0.120" wall tubing will be a little harder. The windshield gussets are 18 gauge, those are MIG'd. I focus most of the weld on the bar, and just "tap" the sheet metal to tie it together.

I do want to get better with TIG, regardless.
The A-Pillar boxes get TIG'd together, and they're pretty straightforward. Corner joint on 1/8th" and I'll have to keep up with adding filler. Seems to come out well enough.

As far as weld access, I basically but the main hoop right against the B pillar and use weld sequence strategy to get 360°. Typically will drill the floor to drop the 4pt, then slide plates under after welding the tops, utilize the sunroof and tack/move as I go, then weld it to the car at the end.

Do you begin to weld in the door bars before dropping the cage? I see that being a possibility if the cage is designed around that idea. But I like to give myself the extra room where it doesn't cost me anything to avoid having door bars in the way. I don't know if that made sense.
Plus, since I usually include a sill bar on the driver's side, it's usually one of the hardest bars to reach because of how low and tucked in a corner the joint is. So that's the other reason for spacing the main hoop away from the B pillar.

You're right, there are several ways to do it. I admire that there's a good array of approaching the same problem.

The tools are nice, although at the end of the day, it's up to us fabricators to figure out how to put the puzzle in the car lol No amount of tooling will do that for us. I heavily appreciate the art that is inherently involved.