Roll Cage Failures

[arse_sidewards]

sure more bars would help, example like this, it appears there was a very pointed impact at that node and without any bars going down in thru window opening (yellow bar) and and any roof bars to help (green) it was gonna fail.

but again its hard to tell with out actually seeing the rig up-close

Yellow would be the biggest single improvement in this case.

Any member that prevents the roof rectangle from turning into a diamond would be the next best improvement. And after that comes V or A in the windshield

 

[chaplinfj60]

on my toyota before i cut it appart i was able to put that yellow bar in, took a bit of clearance work for the dash but was able to get it done.

 

[94toytruck]

My old Toyota was kinda like above but the roof was braced and it was a X-cab so it had a B and C pillar tied into it. There was no windshield spreaders in it and it was built out of pipe and took some pretty hard hits. When it did bend it bent at the A-pillars in the rocker to door area mostly.

 

[willis_racing]

on my toyota before i cut it appart i was able to put that yellow bar in, took a bit of clearance work for the dash but was able to get it done.

Looks like the node on this guy's truck is too far outside the body line to do that effectively. Is it common practice to located the node further inward where you can run a vertical bar without having to forego functional doors, or are most people in the "issa rock crawla, fuck ya doors" camp?

 

['84 Bronco II]

Looks like the node on this guy's truck is too far outside the body line to do that effectively. Is it common practice to located the node further inward where you can run a vertical bar without having to forego functional doors, or are most people in the "issa rock crawla, fuck ya doors" camp?

An Exo cage makes it difficult to add effective triangulation and retain the functionality of doors, hoods, windsheild replacement, etc.

Running the roof bars further inward will allow you to run triangulated tubes through your roof and result in much stronger structure and tighter Exo. There are a few guys with Cherokees/Grand Cherokees doing it this way in the 4600 class.

 

[gt1guy]

Would it be safe to assume that the only reason this rig has the exo cage where it does, is simply for head room? I can't think of any other good reason to do it on a race vehicle.

 

[FlatLander]

Found this gem on fb

That's a Crush Zone Cage.

 

[89Breaker]

this is what i meant by going to the frame.

Ahhh, gotcha. So the downtubes connect to frame through sandwiched plates. I want it to be good for daily driving so I’m struggling with balance of cage safety and daily comfort.

Looking at options to have some parts removable by pins then add back when I want to off-road.

 

[dentedsub]

Ahhh, gotcha. So the downtubes connect to frame through sandwiched plates. I want it to be good for daily driving so I’m struggling with balance of cage safety and daily comfort.

Looking at options to have some parts removable by pins then add back when I want to off-road.

Magazine guys always did this. I've never built a cage yet but it always seemed like a good way to keep out some road noise.

This isn't the best example but the first to come up.

 

[aczlan]

Ahhh, gotcha. So the downtubes connect to frame through sandwiched plates. I want it to be good for daily driving so I’m struggling with balance of cage safety and daily comfort.

Looking at options to have some parts removable by pins then add back when I want to off-road.

Anything more than door bars and you should be using at least bolt in tube connectors like this: Interlocking ID Tube Clamp - Round

A pinned connection is unlikely to be overly strong in compression.

Aaron Z

 

[bdkw1]

Magazine guys always did this. I've never built a cage yet but it always seemed like a good way to keep out some road noise.

This isn't the best example but the first to come up.

A lot of old school pre-runners had urethane mounted cages. I worked on a Walker built one that was probably 20 years old at the time. All the mounts bolted to the frame, not one crack anywhere. It was nice and quiet inside.

 

[gt1guy]

Ahhh, gotcha. So the downtubes connect to frame through sandwiched plates. I want it to be good for daily driving so I’m struggling with balance of cage safety and daily comfort.

Looking at options to have some parts removable by pins then add back when I want to off-road.

You can run sandwich plates or run the tubes directly through the tub. Either way, you want to have a large foot print where the cage meets the tub. You want the force spread out over a large area.

If you're still running the rubber body mounts, where you tie the cage into the frame should be done with the bushing in a tube. If you solid mount the cage, when the frame twists, it's going to twist the tub in ways the spot welds may not be happy with. The bushings have a little give to them, much less than rubber body mounts, but, a tied-in cage helps reduce frame flex too.

One last thing...............Get some pading on that cage anywhere you arms, legs, or melon can make contact. Cages are a great piece of safety kit, but they can also kill you.

 

[NDCjeepsmith]

If using the "leaf spring bushing in a tube" type mount I've always made the bushing be part of the body plate. Not the mount to frame. Once when rolling around a chassis with no body on yet but the cage bolted in to save room on the floor i felt the cage pivot on the frame mounted bushings and ever since I've had fear of a mount like that allowing cage to "swing" away in a hard side roll.

May have just been a fluke moment but if the body gave way at plates I see them becoming pivot points.

 

[Rockwood]

One thing missing from this thread (I don’t think I saw a single cage with it other than 4675):

Get some goddamned SFI padding for your cage. Not pool noodles, not water pipe insulation, SFI padding. I doubt many are wearing helmets while wheeling, and even if you are, 2.0 x .120 DOM will STOMP your helmet to dust. I’m surprised that any sanctioning body lets anyone race a car with zero padding.

And if one of you fuckers says something like “I wiggled in my seat and my idiot noggin don’t touch nuthin” I’m personally removing the fleas from a thousand camels and dumping them in your chones drawer.

 

['84 Bronco II]

One thing missing from this thread (I don’t think I saw a single cage with it other than 4675):

Get some goddamned SFI padding for your cage. Not pool noodles, not water pipe insulation, SFI padding. I doubt many are wearing helmets while wheeling, and even if you are, 2.0 x .120 DOM will STOMP your helmet to dust. I’m surprised that any sanctioning body lets anyone race a car with zero padding.

And if one of you fuckers says something like “I wiggled in my seat and my idiot noggin don’t touch nuthin” I’m personally removing the fleas from a thousand camels and dumping them in your chones drawer.

Good point, I was recently wheeling with a member from this board who won a trip to the ER from smacking his head on a cage even though he was wearing his harness. You don't want your cage creating an additional safety hazard

You should try to keep tubes as far away from driver's and passengers' heads when you build your cage, and anywhere there could be cranium to tube contact should be padded, especially if you aren't planning on wearing a helmet.

 

[Rockwood]

Good point, I was recently wheeling with a member from this board who won a trip to the ER from smacking his head on a cage even though he was wearing his harness. You don't want your cage creating an additional safety hazard

You should try to keep tubes as far away from driver's and passengers' heads when you build your cage, and anywhere there could be cranium to tube contact should be padded, especially if you aren't planning on wearing a helmet.

Yeah. Buddy of mine was testing his Touring Car (door slammer wheel to wheel racer) on the street and got rear ended by someone. Didn’t even damage anything beyond the gutted bumper, but he smacked his noggin on the cage and got to spend the night in the ER.

This is the shit I run:

Dual Durometer SFI 45.1 Roll Bar Padding - Pegasus Auto Racing Supplies

Dual Durometer Roll Bar Padding absorbs minor bumps and low-speed impacts, but if heavier impacts occur, the force is absorbed by the SFI-rated inner core. The softer outer layer is easy to remove.

www.pegasusautoracing.com

 

[SLOWPOKE693]

Good point, I was recently wheeling with a member from this board who won a trip to the ER from smacking his head on a cage even though he was wearing his harness. You don't want your cage creating an additional safety hazard

You should try to keep tubes as far away from driver's and passengers' heads when you build your cage, and anywhere there could be cranium to tube contact should be padded, especially if you aren't planning on wearing a helmet.

Another thing I learned a long time ago from a great chassis builder..... Never EVER point a tube at the drivers compartment.

Yeah. Buddy of mine was testing his Touring Car (door slammer wheel to wheel racer) on the street and got rear ended by someone. Didn’t even damage anything beyond the gutted bumper, but he smacked his noggin on the cage and got to spend the night in the ER.

This is the shit I run:

Dual Durometer SFI 45.1 Roll Bar Padding - Pegasus Auto Racing Supplies

Dual Durometer Roll Bar Padding absorbs minor bumps and low-speed impacts, but if heavier impacts occur, the force is absorbed by the SFI-rated inner core. The softer outer layer is easy to remove.

www.pegasusautoracing.com

I run the same stuff on the cage of my SxS. Like you, I'm totally shocked there are no rules about cage padding in many forms of racing. In circle track back in New England the rule was any bar a driver can touch with their hand has to be padded. Sounded legit to me...

 

[94toytruck]

My friend rolled years ago and hit his head on his cage that was padded. Didn't think much of it, a few days later he went to a Dr. cause he had a headache that wouldn't go away. He had a fracture on his skull where it hit the tube. It probably saved his life but honestly if the cage was built properly he'd have never hit it. These are problems most don't think of shoving a interior cage in vehicles.

 

[Rockwood]

My friend rolled years ago and hit his head on his cage that was padded. Didn't think much of it, a few days later he went to a Dr. cause he had a headache that wouldn't go away. He had a fracture on his skull where it hit the tube. It probably saved his life but honestly if the cage was built properly he'd have never hit it. These are problems most don't think of shoving a interior cage in vehicles.

I hear what you’re saying, but in a bad wreck with a regular sized cabin, there will be noggin to something contact. Not might. Will.



Belts stretch. A lot.

 

[SLOWPOKE693]

Belts stretch. A lot.

So does ones neck when not wearing some form of HANS device.

 

[gt1guy]

Not looking at the roll cage as part of a system can have very bad results. Roll cage, belts, seat, padding, helmet, all work together.

The SFI 45.1 padding posted above is designed for a helmet hitting it. All real padding is designed for a helmet hitting it. That's why it's so hard. It's damn good stuff for what it was designed for, but it's not a soft landing for your melon.

Here's the part all of us recreational wheelers, and those who also drive on the street run into a problem.

If you have a full cage, you should be wearing a helmet.

Myself, I plan to wear a shorty or mountain bike helmet offroad. But on the street........that's a tough one and I know I should.

I guess it comes down to what my buddy likes to say, "Let your conscious be your guide".

 

['84 Bronco II]

Not looking at the roll cage as part of a system can have very bad results. Roll cage, belts, seat, padding, helmet, all work together.

The SFI 45.1 padding posted above is designed for a helmet hitting it. All real padding is designed for a helmet hitting it. That's why it's so hard. It's damn good stuff for what it was designed for, but it's not a soft landing for your melon.

Here's the part all of us recreational wheelers, and those who also drive on the street run into a problem.

If you have a full cage, you should be wearing a helmet.

Myself, I plan to wear a shorty or mountain bike helmet offroad. But on the street........that's a tough one and I know I should.

I guess it comes down to what my buddy likes to say, "Let your conscious be your guide".

I know wearing a helmet driving on the street looks and feels retarded, but the likelihood of being in a bad enough wreck where you would want the helmet is much higher on the the road for most people who aren't racing. I think what it comes down to is keeping tubes as far away from the driver and passengers' heads as possible, and padding any tube that could possibly make contact is a good idea. If having tubes close to your head is unavoidable, you should seriously consider wearing a helmet.

 

[Rockwood]

Not looking at the roll cage as part of a system can have very bad results. Roll cage, belts, seat, padding, helmet, all work together.

The SFI 45.1 padding posted above is designed for a helmet hitting it. All real padding is designed for a helmet hitting it. That's why it's so hard. It's damn good stuff for what it was designed for, but it's not a soft landing for your melon.

Here's the part all of us recreational wheelers, and those who also drive on the street run into a problem.

If you have a full cage, you should be wearing a helmet.

Myself, I plan to wear a shorty or mountain bike helmet offroad. But on the street........that's a tough one and I know I should.

I guess it comes down to what my buddy likes to say, "Let your conscious be your guide".

The SFI 45.1 padding I linked has a soft, non-SFI outer cushion, with the SFI inner cushion under it.

 

[AK_F250]

I know wearing a helmet driving on the street looks and feels retarded, but the likelihood of being in a bad enough wreck where you would want the helmet is much higher on the the road for most people who aren't racing. I think what it comes down to is keeping tubes as far away from the driver and passengers' heads as possible, and padding any tube that could possibly make contact is a good idea. If having tubes close to your head is unavoidable, you should seriously consider wearing a helmet.

It's a stupidly avoidable problem in aviation too. I've personally seen one firsthand and heard about several other seeming mild crashes in small tandem planes like super cubs where they would have walked away a little sore if it wasn't for the crease in their skull from the diagonal brace over the pilots head.

 

[Mr.510]

While this thread on the subject of roll cage padding, helmets, and such I'd like to throw in a few thoughts. First, I am the only living person I'm aware of with an actual roll cage dent in their skull. I compression fractured the back of my skull on the wedge bar in the main hoop of my baja'd Datsun 1200 in 1991. The cage was 1-1/2" .120 wall ERW and absolutely, positively saved my life. It also gave me 30 years of chronic migraine headaches and debilitating back and neck injuries. The bar I hit my head on was padded with proper roll cage padding, but it was made in 1989 so a modern pool noodle might be equivalent? This was on the street so of course I wasn't wearing a helmet. I was stopped on a two lane highway waiting to make a left turn in my 1600 pound "Ratsun Baja" and a ~3000 pound Accord going ~50mph hit me about a foot off-center to the right. Bitch never even touched the brake pedal. The impact ripped the front seat mounting rail out of the floor and I went backwards into the back seat area. I hit my head on the wedge bar on the way. In addition to the skull fracture, my head was forced forward so far that my chin bruised my sternum and I chipped a bunch of teeth. Basically, it almost ripped my fuckin' head off and I spent six months in a neck brace.

If I'd had a harness bar in the main hoop I might have walked away from that accident without serious injuries. This was a street car, and they're full of compromises. I didn't put a harness bar in it because I wanted to be able to recline the driver's seat. Hindsight being 20/20, I haven't driven or ridden in anything with a cage and no harness bar since, and I preach about the need for them and their proper placement to anyone that will listen.

Another thing to consider when thinking about how far you can stretch to hit your head (and other body parts) on stuff is that even most race seats will bend in a hard impact. NASCAR requires that the back of the seat be bolted to the harness bar. You can have a mount in between to place the seat where it needs to be, but the seat back has to be solidly mounted to that bar. Their reason? If your seat moves, bends, or breaks your belts are instantly loose. We all know how easily loose belts can kill people. Never rely on the strength of a seat to keep your belts tight! If you go fast, mount your seat back like your life depends on it, because it might.

Minor sub-rant: Tighten your belts if you're going fast or are in a place you could endo or otherwise take a really hard hit. Having your shoulder belts an inch looser can let your head move six inches further in a hard impact. Not to mention compressing your spine, breaking your clavicle, etc. They taught us that in rally school, and it was repeated at many driver's meetings.

 

[Bebop]

Another thing to consider when thinking about how far you can stretch to hit your head (and other body parts) on stuff is that even most race seats will bend in a hard impact. NASCAR requires that the back of the seat be bolted to the harness bar. You can have a mount in between to place the seat where it needs to be, but the seat back has to be solidly mounted to that bar. Their reason? If your seat moves, bends, or breaks your belts are instantly loose. We all know how easily loose belts can kill people. Never rely on the strength of a seat to keep your belts tight! If you go fast, mount your seat back like your life depends on it, because it might.

Sparco says you shouldn't do that because it impacts how the seat is designed to flex during impact.

No WRC car or DTM or whatever other top racing vehicle has a hard shell seat that has a bolt back rest.

Seat choice has an impact on your statement.


What I gathered from your story is that if your vehicle has a roll cage, you should wear a helmet.

 

[arse_sidewards]

What I gathered from your story is that if your vehicle has a roll cage, you should wear a helmet.

For street vehicles that's about as realistic as "just say no to drugs"

He would have been dead without the cage because the Accord would have tried to share the cabin with him. Sounds like the cage did it's job and the seat failed.

 

[Rockwood]

Sparco says you shouldn't do that because it impacts how the seat is designed to flex during impact.

No WRC car or DTM or whatever other top racing vehicle has a hard shell seat that has a bolt back rest.

Seat choice has an impact on your statement.


What I gathered from your story is that if your vehicle has a roll cage, you should wear a helmet.

FIA certified seats are the only ones that are generally exempt from seat back supports.

 

[Bebop]

FIA certified seats are the only ones that are generally exempt from seat back supports.

agreed

 

[SLOWPOKE693]

I run a Corbeau(sp) hard shell seat in my race car and it has a bolt hole molded in to mount the back of the seat to the harness bar, and it's used in my car. I also tighten the living fuck out of my belts over and over right up until the green flag drops, but I'm guilty of not wearing a head/neck restraint. I need to pick one up this winter.....