roll cage

[djscheppy]

what is used in making a roll cage as

what metal and stuff?

would be interesting to know about the build uip of a roll cage and digrams of points that it should go into and so on


jon

[Jonny Rochester]

You can't use aluminium. You can't used high strength 4130 cro-moly, unless you are going full international spec.

For CAMS in Australia, you need to use mild steel (or a low carbon steel specified in their manual), and the tubes have to be 1.5" diameter I think. The wall thickness is specified also.

Buy the CAMS handbook, its about $50 and has everything.

Basicaly you need a 6 point roll cage. A center hoop, bars going back toward the rear shock mounts. Front bars going down the A pillar to the floor. Side intrusion bars. For some racing the roll cage has to be within the cabin (not go threw the firewall), and often the cage can not extend rearward of the main suspension points.

Where the vertial tubes meet the floor, they have to be welded to a 2mm thick boxed fotting I think. A bolt in cage needs thick plates bolted to the floor.

Welding is done with a MIG, and often you have to strip the car and take all glass out to do it.

[Steve-AE86]

roll cage material has to be 'cold drawn' pipe. that is to say, the pipe has no seam on the inside. must also be of no less than 3mm wall thickness.

[mattysshop]

you don't have to MIG, you can TIG also..

[Dorio86]

Is there a reason why you cannot use Aluminium or chrome molly?

[Steve-AE86]

you can't use aluminium cos it's too weak, and brittle.

you can use chromolly, but it's WAY expensive, and only needed for international level cages

[Dorio86]

I see, I don't want to be a pain but if aluminium is weak, why is the chassis of a NSX made completely out of aluminium?

And chromolly is WAY too expensive but how expensive is it here?

[Monk]

i her dits cheaper to buy a bolt in then to make one yourself?

[Monster]

Well then why start?

I'm pretty sure the NSX body is aluminium as well as most of the suspension components. I think the main chassis is still a very light steel.
(Me thinks )

[Blown86]

CAMS banned aluminium cages quite a few years ago.
I thought you'd know this if you'd rallied for 10 years as you've claimed before, it's been covered many times in CAMS newsletters and bulletins, materials specs and design are listed in the CAMS manual.

The biggest problem with aluminium is that it may well be ok when new but it will work and age harden becoming brittle and losing strength with age and stress.

Chrome moly is fine for any cage but probably overkill for a non load bearing cage due to cost. It is also much harder to weld and bend than low/medium carbon steel.