Roll Cage Construction.

[RAZOR32]

"i Know that a cage was built by a new Hobart bloke a while back in a supra and the front leg collapsed as it rolled down a hill and crushed the blokes finger on the steering wheel. its bad enough having a crash but watching the cage crumble around you as you are crashing isnt a good sight."

I’m not aware of the one you mention could be a different one? Or someone told you the wrong story. The only supra I know of that has rolled was a silver auto JZ80 TT up at the Collinsvale hill climb about 18 months ago, it rolled a number of times down a step bank hitting a tree on the way and ending up about 50 meters off the road. (In Kieran’s pic’s above)

Az and Kieran put the cage in that Supra, the cage held up well and save the guy from any injuries, the front right leg did get a bend in it as that’s what made contact with the tree but did not crush his hand to the steering wheel.

I was there at the time, I think the cage saved the guys life!

Az has built many cages with YT and you cannot tell their work apart they both look the same, I’m confident that Az is as good as anyone in the state at cages.

Any way back on topic

Edited August 30, 2009 by RAZOR32

[Roy]

So wat is a decent target weight for a 6 point cage with side impact, bit not going crazy with all the diagonals as the car is a circuit car and A) dotn expect to hit any trees out there and B) dont need the chassis rigidity.

I ask becaue for personal comfort i can run std doors and minimal side impact and a certain weight. Or go much more comprehensive cage which makes access shit, but allows me to run carbon doors. But whats the point of taking 30kgs of weight our of doors if the additional weight of the cage offsets it?!?!

Keeping in mind this is only a club track-super spritn car

[unique1]

my cams/andra approved 6 point CDS cage weighs around the 55kg mark when sent to me, it needed to be cut to the lengths etc so that would offset the weight of the welds, so around the 50-55kg mark and its got all the corner gussets etc, not too basic yet not extreme like some of them.

Edited August 30, 2009 by unique1

[DJRIFT]

It would appear that i did get the incorrect story then but even still Yes its saved his life but given that supras have such a sloped A pillar and are known to squash flat in roll overs this would be a prime example to go for double front legs and or maybe tagged off to the body.

its a good example to show that CAMS say this is the minimum requirement, but is it really.

I deliberately didnt mention any names as i wasnt looking to bad mouth any body just making a point. the point is that maybe the cage builder should have said this wont be safe enough. the car was entered in targa tas only months before this crash, imagine what it may have been like after seeing it go off the road at over 200km/h instead of 70 or 80.

simply making the point of safety not who make what cage. i i understand that it may be all the tight ass owner wanted to spend but if i was building safety cages for peoples safety i would be saying the minimum will do.

i look at it like the basic cage is only good for basic entry level track work. and if your crazy enough to throw your self at big trees being gravel or tarmac rally then you need more than basic. i know plenty of people that run less than adequate cages in targa but that their own choice and not mine so i make these points from my interpretation of a safety cage.

So wat is a decent target weight for a 6 point cage with side impact, bit not going crazy with all the diagonals as the car is a circuit car and A) dotn expect to hit any trees out there and B) dont need the chassis rigidity.

I ask becaue for personal comfort i can run std doors and minimal side impact and a certain weight. Or go much more comprehensive cage which makes access shit, but allows me to run carbon doors. But whats the point of taking 30kgs of weight our of doors if the additional weight of the cage offsets it?!?!

Keeping in mind this is only a club track-super spritn car

Roy i was totally surprised by how light the proper roll cage material is. you will save more than 30KG with carbon doors and you would probably put in about 10kg extra in bars. the main point that i see is that the roll cage is still safer than the structure of the door if its on the track or in the bush its worth having.

[klusio]

whats the deal here? You buy a kit cage, liturally slap it in it, your suddenly the expert and have the right to openly

critise a much more qualified, experienced and professional product? My responce is go have sit in your car and have

second thought about the misa-lined, unlevel, butchered, undercut porus welded bars currently installed in your vehicle,

I'd meet some standards before administering them on others.

the cage was built to cams regulations all by the book, its fully removable cant tag it off to the pillar

the cage is built from the same materials and is exactly the same design as yours minus the centre bar.

All to the book right down to the last full stop.

The crash its self was more than simple roll over there was marks on the trees several meters off the ground

well out from the bank/cliff and would have been traveling faster than 80km.

whats the difference between putting a car on its lid at 200km at the track?

Chances are the end result will be the same hospital.

At the end of the day its only added safety no matter what you do, we build cages

to suit the user and their requirements, offering them best advice possible with the design and budget.

END RANT.

Edited August 30, 2009 by klusio

[sav man]

have a look at marks targa gtr that rolled down the 50m cliff in targa 07, and comparte it to that supra. the supra cage might have saved his life, but if that happened to me, i wouldn't race it with-out redesigning the front legs. good thing he didn't have a bendy jap cage though.

our targa car has a dody bolt-in, with front section almost identicle to the supra. dad dosn't want to put a proper cage in it.....one of the reasons i'm building my own car.

maybe a thread needs to be started to just discuss cage design, so this one dosn't get ruend.

[DJRIFT]

Kiran, this could go on for ever so for the sake of the topic its over for me.

[Duncan]

this pic? sorry about the stuff in the way

this car left the road pretty slowly too but managed 6 or 7 rolls down the hill. basic cage shape remained intact

[Risking]

Im not even going to comment on the above posts.

I can see major flaws with the AE86 and the Supra and the skyline for that matter, but its not my place to say anything as im sure people probably have comments about the job Ive been doing too.

At the end of the day if the person racing the car is happy with the job then thats what matters as its them who's putting their faith in the job.

On anpother note we now have the rear section crossed up and the rear legs all but welded into the car.

Left to do id the main hoop cross, the base plates and boxing then the firewall penetration.

Ill do write up latter about the rear section and how the legs are done and welded up properly.

[Risking]

and before anyone comments, id say im more than "qualifed" to build cages................

[Bozman1]

Yes, don't ruin this thread....as I am enjoying watching the pic's Brad is putting up of my little 180

Pete Muir from Bond gave me this cage for a super price, and Brad is doing a superb job on the install with all of the additions that he and I have discussed.

I have driven so many cars over the years, some with no cages, some with ones that you laugh at, and some you just drool over.

This is this first major mod I am doing to the car......next the upgraded brakes and the fine tuning of the already modded suspension, and last will be power.

Cannot wait to get back from my Toyota Hilux Heroes driving duties on the 14th September, so that I can actually go over to Brads little shed and see what he and the boys have been up to in real life

Top work Brad, keep us all updated with the thread

Looks like the little thrash, skid, rally, track 180 has changed a bit since Brad took it

[PHaT MR30]

and before anyone comments, id say im more than "qualifed" to build cages................

Now thats the sort of cage I would be happy with!

[Risking]

Yes, don't ruin this thread....as I am enjoying watching the pic's Brad is putting up of my little 180

Pete Muir from Bond gave me this cage for a super price, and Brad is doing a superb job on the install with all of the additions that he and I have discussed.

I have driven so many cars over the years, some with no cages, some with ones that you laugh at, and some you just drool over.

This is this first major mod I am doing to the car......next the upgraded brakes and the fine tuning of the already modded suspension, and last will be power.

Cannot wait to get back from my Toyota Hilux Heroes driving duties on the 14th September, so that I can actually go over to Brads little shed and see what he and the boys have been up to in real life

Top work Brad, keep us all updated with the thread

Looks like the little thrash, skid, rally, track 180 has changed a bit since Brad took it

Like Boz said we have discussed this cage at great length and planned what both john and myself were comfortable doing with it. The way we both see it is that the car will be capable of some serious pace and if it was ever involved in an accident there should be no "i wonder if we did this instead"

It has changed alot over the last few weeks, from a stocker 180 to this already.

Ive got a few little projects on the go that you are as always more than welcome to drop by a check out mate.

Now thats the sort of cage I would be happy with!

Thats the exact reason that cage is in my own GTR. Its pretty intense and can be a pain in the arse at times but I feel safe and know there will be no if buts or maybes should it be involved in an accident.

I honestly rekon anyone doing any form of motorsport without a good cage is an idiot.

Weight, road car bla bla I dont think is a good enough excuse for not having something.

I do have a genuine question for klusio..

Why have you done the main hoop cross like that??

The idea of the cross is to provide strength to the hoop from bend to base to stop it folding over in a roll.

I know access to the rear is valuabe etc but id have thought being a rally car you'd want as much strength as possible?

[Roy]

Weight, road car bla bla I dont think is a good enough excuse for not having something.

If its a daly driver then in my eyes thats a perfectly good reason not to go crazy with the cage. I need to carry things in the back set so need to access the back seat area. I drive my car to the track and 4 wheels do not fit in the boot, so i again need to be able to get rims and tyres back there.

Also the weight, for a club car that is only used for motorkhanas and a 5-6 days a year at Supersprints, in a car that isnt all that quick then again i see those as perfectly good reasons for going without. Side impact with front legs would be great, but i dont see too many trees/posts etc as road/track side risks. Again, getting back to it being a road car that i haev to drive to construction sites and through refineries

[Risking]

I do agree which is why I said something. I see alot of skylines and silvias running around doing sub 10's at wakefield without even a decent hoop and rear legs.

[timsr33]

another question brad what type of filler fire do you youse

is it a high carbon filler

low carbon filler or a mild steel one or doesnt it mater

and is it true that you have to get the cage inspected once you have droped it and welded the tops or is this just a mith

thanks tim

[Marlin]

Good thread, with lots of opinions

Something I've noticed crawling through here, is some people choose not to have a horizontal B-pillar (taxi) bar....

I insist on one for my car, and I'm not referring to cage strength, but rather harness mounting. I cringe when I see guys heading into stage/track with harnesses attached to or near the parcel shelf and the shoulder straps are sagging. It's more common that you may think. It'd be possible to have your shoulders come out of the harness.

I like my harnesses attached to the B pillar taxi bar, much less chance of stretch in a big one. I also make a point of doing my harness up absolutely as tight as I can, wiggle into the seat, cinching it down.

A good point to remember I think; correctly installing and wearing of a harness is just as important as a cage!

[sav man]

Good thread, with lots of opinions

Something I've noticed crawling through here, is some people choose not to have a horizontal B-pillar (taxi) bar....

I insist on one for my car, and I'm not referring to cage strength, but rather harness mounting. I cringe when I see guys heading into stage/track with harnesses attached to or near the parcel shelf and the shoulder straps are sagging. It's more common that you may think. It'd be possible to have your shoulders come out of the harness.

I like my harnesses attached to the B pillar taxi bar, much less chance of stretch in a big one. I also make a point of doing my harness up absolutely as tight as I can, wiggle into the seat, cinching it down.

A good point to remember I think; correctly installing and wearing of a harness is just as important as a cage!

also safer if you go in backwoulds Porsche style and your seat mounts brake. Less room for the harness to get slack.

[Risking]

Alot of people use generic mild steel rods but from the engineering Ive had done in the past im told they dont have enough tensile strength, so for anything that does not need to be inspected mild steel filler would be fine but if it does need to be engineered then er70s-6 is required or er70s-2 is more prefered but expensive.

I use er70s-6 on pretty much everything and -2 on anything molly or CDS if the owner wants to spend a few bucks more.

As for inspections it is advisable to have the cage looked as it is constructed If the design falls outside the basic CAMS guidelines as if there is a problem it can quickly and easily be rectified.

Cages like this only require certification from the fabricator and they are typically looked at when the car is pre scuited before its first meeting.

So no this type of cage does not require any inspections of roof welding etc etc.

Its crazy, the space frame GTR im building has to have the cage inspected but the chassis its self can be built from water pipe and welded with a ARC welder for all cams care.

Ive always put the horozontal bar in my main hoops.

Every hoop ive done has a full diagonal cross and a horozontal bar. Same as the rear , full cross between the legs.

I wont do a cage unless the hoop is crossed, rear legs are crossed, intrusions are done to the bends or very close to it (depends on the height of the leg bend etc), dash bar between the front legs and there is some form of V or cross in the roof.

To me thats the bare minimum a circuit car should have. Typically things go a little further like old mate Boz's car here.

Edited September 3, 2009 by Risking

[klusio]

I do have a genuine question for klusio..

Why have you done the main hoop cross like that??

The idea of the cross is to provide strength to the hoop from bend to base to stop it folding over in a roll.

I know access to the rear is valuabe etc but id have thought being a rally car you'd want as much strength as possible?

Yeah I can see your point there, the car isnt that serious Im building it for an all round fun car motorkana, super sprints

hill clmbs, drifting maybe a fun day at the drag strip.

The main reason for the cross falling short of the bend was connecting with the center lines from the rear horizontal bars and

side intrusion, it has the diagonal to support the hoop on the drivers side, I chose to leave the extra cross bar out for ease of access.

There is always improvements to be made, give it a couple of years I recon I'll look at another cage for it, as this one is rather basic.

I was curious to hear your throughts, if you have time shoot me a pm

Cheers Kieran

PS. cage build looks good, nice to see someone finally explaining the amount of work involved

people just dont understand when it comes to costs.

Edited September 3, 2009 by klusio