Roll Cage Design Preferences - Features / Benefits / Advantages / Disadvantages

[DETON8R]

Question for anybody who fabricates or installs cages - What is your preference for a cage design? And WHY???

I'm custom bending a roll cage for my 1969 Camaro. I started with a pre-bent weld in 10-point cage kit that a purchased from someone else who chose not to use it. The fit of the cage was good for a standard '69 Camaro, however I'm doing some interior mods, a dash swap and setting the B-pillar hoop back a bit further than it would normally be placed in the car according to the instructions, so I had to decide to either make some custom modification to fit the car, or go another route. I kinda did both....

What I found was the pre-bent kit bar elements there were some pretty sizable gaps between body parts of the car and the bars within the cab from the pre-bent kit. I wanted a tight fitting cage (tight enough to make the guy putting in the head liner really mad) and the most head room and clearance between me and the cage that I could possibly have inside the car. I used the B-pillar hoop, massaged it a bit for my build, and then went custom for the rest.

In my research on the subject, I found this image in the NASA Rally Sport Rule Book.
http://www.nasarallysport.com/rules-forms/2012-NASA-Rally-Sport-GRR-Appendix-B.pdf

I chose to bend a roof hoop, shown as a "Halo Hoop" and ditch the two door opening bar configuration shown as the 253-3 configuration, as I just couldn't massage the door openings to make it work the way I wanted it to.

The advantage I see is that the two most complex bends are done as a single members, then the other bars are bent on fairly simple straight runs.

What are the factors to consider when choosing a design-style for a cage?

[DETON8R]

what are you using for a tubing bender?

i bought an alston 10 pt kit for my 1st gen camaro, but will modify it as i have to for the exact fit i want.

i no longer have a bender so will have to go to my local muffler shop if i need anything bent. but the muffler bender distort the tubing a lot...

I'm using that kind. Don't know much about it, I borrowed it, it works. The bar makes the bend slightly oval, however according to the NASA rulebook, it is less than 10% distortion. The "factory bends" from the CAC kit I have are 3% to 6% distortion, and mine are a bit more than that, but not much... I've seen other "factory bent" roll cages and the distortion is the same or even worse then what I'm using, sorry I won't use their names.

[DBasher]

I'm not an expert or even a know it all. :secret: I've only built/installed a total of 3 cages, the last one being rule specific.

I really like the Halo design and will be doing this on my Barracuda. I think adding an X in the Halo will help with some of the triangulation.

On the bar behind the front seats, I've got two down bars from the intersection of the main hoop and cross bar down to the frame. This just gives another mounting point and more area to take an impact.
Something else we did was add a bar on both sides from the front down bars to the main hoop. We have the typical door bar but wanted more, it runs just above the rocker front to back.

Seat mounting plays a big part as well. If you can tie your seats into the cage, doesn't do much good if you're being thrown around the inside of the cage.:confused18:

The cage for my bronco was designed totally different than the Studebaker. I wanted a smooth bar up high to slide against obstacles without hanging up.

I'll be at my dads place tomorrow, I'll grab some pictures of the Studebaker cage so you have an idea of what we did.

Without looking at your build, what are the plans for the car?

:cheers:
Dan

[DBasher]

Obviously I have used my mad CAD skills for this...:sarcasm_smiley:

[DETON8R]

Without looking at your build, what are the plans for the car?
Dan

Nice CAD work there!! I think we are looking for more engineers at work...

I'm going to drive it as a street car for the majority of its future life, I commute to two different locations for work, whichever work location I go to involves long mountain roads, with big changes in elevation. :unibrow:

Will also be going to shows and club events with the local Camaro Club as the Pro-touring example wherever we go. I want it to stand out as more than just another first gen Camaro, with a bit more rigidity, and a lot more handling ability. Will hit some auto cross events throughout the year, Good-Guys at the Alameda County Fairgrounds, and a few other auto cross race venues around here like Marina, and maybe even Laguna Seca.

I will be installing removable door bars and the seat back bar. Not sure I'm going to do too much more in terms of other bracing, maybe a V or X inside the halo hoop, that's probably it. Since I wont be wearing a helmet for the majority of the time I'm driving, I'm not sure I'm going to put much more steel into the cage.

[Tuske427]

Here are a couple of links I found when building my cage. I built mine from scratch... I hope this helps.

http://www.nwhydroshots.com/links/rcd101.htm

http://shop.dj2motorsports.com/Roll-Cage-Design-and-Construction-Basics-PDF-Version-RCDCB2011.htm

http://www.pirate4x4.com/articles2/tech/bendin_tube

[Tom Fuehrer]

Here are some pictures of the most recent Camaro cage I did. It is a Vintage Race '67 owned by a friend of mine.

I usually use the Halo-bar scheme in my cages. As you mentioned it is easier to make simple bends instead of complex. I also like running the front down tubes through the dash. It gives you more space to swing your legs into the car. The owner of this car is pretty tall so the main hoop is back pretty far.

My own race car has the bar farther forward and tilts back at the same angle as the front edge of the Quarter window. That is a trick I learned from Mark Stielow's Mule build up. If you can find his build book it shows a lot of great details for building a cage.

I also recommend adding padding to the halo bar. In a street car your bare head is close to an immoveable object. Use the dense SFI 45.1 stuff, not pipe insulation!

[3Deuce]

I also like running the front down tubes through the dash. It gives you more space to swing your legs into the car.

This is key. You'd be amazed how much easier it is with the front bars through the dash. Plus then it's easier to hide it behind the pillars.