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rollcage mountings

Posted: Thu Jun 05, 2014 5:49 am
by soal6
I'm needing to weld up an exterior roll cage, nothing too extravagant. I just wondered what peoples thoughts were regarding on where to mount it. Body or chassis?

Re: rollcage mountings

Posted: Thu Jun 05, 2014 6:30 am
by kiwizook
chassis definitely, as it will otherwise just rip off in a roll over, body and all. I recommend putting rocksliders on as well, and mount your cage to that. have a look at some of the builds on here, it'll give you some good ideas regarding rocksliders/cages

Re: rollcage mountings

Posted: Thu Jun 05, 2014 8:56 am
by soal6
Perfect cheers. I'll go have a look about

Re: rollcage mountings

Posted: Thu Jun 05, 2014 9:21 am
by Anton
Is this for a road legal car?

Re: rollcage mountings

Posted: Thu Jun 05, 2014 11:05 am
by ScottieJ
chassis, use a minimum of some 3mm plate for some spreader plates on the chassis, at least 100x100mm perferably bigger, spreader plates are essential, in a bad rollover the cage could rip your chassis without them.

Then for the rock slider outriggers minimum comp spec is 75x50x3mm box section, if not for comp use you could just use 50x50x3mm box of the same size tube as you are using for your cage.

Re: rollcage mountings

Posted: Thu Jun 05, 2014 8:34 pm
by soal6
Anton, aye it is for a road legal Sammy. Whats happening is, I've signed up for an offroading weekend with the bordc guys up here. Because I've got a fibreglass top they won't let me do some parts of the quarry. If I cage it I'm good to do the whole thing.

Scottiej, spot on, thank you for that information. I'll get the steel looked out. I thought I would do 2 hoops, one intro t of the door and one behind. Linked from front to back above the roof. Would that be sufficient do you think?

Re: rollcage mountings

Posted: Thu Jun 05, 2014 9:55 pm
by ScottieJ
I would put at least one diagonal in the roof or a X and if you can run some stays down to the chassis at the back or to a box/tube rear bumper if you have one, preferably with a diagonal/X between them.

Re: rollcage mountings

Posted: Fri Jun 06, 2014 8:18 am
by kiwizook
as scottie said, put diagonals in there. diagonals will give it all the strength it needs and ever will have. bend the front hoop around the top of the windscreen, and also weld in a brace at the bottom of the windscreen

Re: rollcage mountings

Posted: Fri Jun 06, 2014 6:28 pm
by Anton
Because it's a road legal vehicle, you can't weld to the chassis without risking VOSA pulling you and making you IVA test the car.

If it were me, I'd drill the spreader plates, put bolts through the holes, weld them in and grind it flat again so that when you weld it down, you'll make it look like it's bolted, not welded.

But I'm far more paranoid about VOSA and the DVLA than most people!

Re: rollcage mountings

Posted: Fri Jun 06, 2014 7:03 pm
by ScottieJ
Anton you are allowed to weld additional brackets and mounts to the chassis without any worry of getting into IVA territory. It's only if you modify the chassis rails (drill, notch, shorten, extend etc) or structural crossmembers that they class it is radically altered. You are even allowed to move body mont outiggers according to the ACE website.


http://www.the-ace.org.uk/chassis-and-m ... ification/