Did our first track day yesterday at Blyton....dont think it will be our last. However when i was passengering i felt very exposed in our Tiger Avon without a roll cage. Also when we looked at the photo's we had taken it was very noticeable that the top of my lads crash helmet is higher than the height of the standard rollover bar.
Ive read the posts on here about all the rules and regs about roll cages for racing but this car will not be used for racing so i was wondering whether anyone has any info on DIY roll cages. Ive seen some photo's in dave1888's photo archive where he appears to attach the front hoop to the chassis by bolting through the body panel . I am reasonably profficient with a mig welder so would like to have a go at building my own if i can
Any views or advice welcome
Thanks
Ian

This was my front hoop, i subsequently gave it away as not MSA standard



It bolted through to the frame, It was made from 1.5" CDS, I designed it then ordered from a chap on eBay as a flat pack, I think this is him

http://www.ebay.co.uk/usr/tube-bender?_trksid=p2047675.l2559

This was the design I wanted



It cost around £70 delivered, then got welding.

to land on the existing frame easily would have required a lot of work, pulling off the panel etc so I mounted on the outside, cut a 1.5" end of tube, capped it with 1/4" to plate then drilled through the plate to bolt to the frame inside.

The bolt a then hidden in the tube.

Here's mine, two triangular plates welded to the junction of chassis tubes on the floor, two bits of bar fitted into the tubes with an M10 thread down the middle, two 10mm internal diameter tubes welded into the existing cross bar and job done!

If you need any more photos let me know...

http://www.locostbuilders.co.uk/viewthread.php?tid=154122

If you are considering doing any MSA speed events (Hillclimbs or sprints) then from 2016 all "Road going - Specialist Production Cars" will require a ROPS which complies with the requirements set out in the MSA Blue Book.

A "Locost" type Seven would fall into this category.

If you are making a cage you would be best to follow the blue book requirements.

The thing is that all of the MSA rules and regs are there to insure that the Roll cage is safe, so if you are making your roll cage to improve the safety of you car then following the MSA rules and regs is probably the best place to start.

The blue book is availiable to read for free on the internet or as every member gets a new paper copy every year somebody would probably donate a 2014 or older version

This is probably the clearest picture of my cage:


Description

This has full FIA homologation and to be honest isn't really any more complicated than the non MSA cages I have seen. Also the small extra cost to make a proper cage would easily be offset by the increased value when/if ever you came to sell the car by having a proper approved cage.

I've got the Caged Laser cage on my Avon. Very pleased with it. Tiger did a good price for me, so always worth asking them. If I'm honest it is a little heavy and could maybe be narrower tube, but it's not a competition car and it feels a lot more rigid and safe now.

Happy to provide any reference measurements, etc. if you go your own way.

Thanks for the replies. 'Doctor' did you make your cage? I see you're in Derby, I'm in Ripley, would it be an option to come and have a look. I agree re the regs as I am fitting the cage for safety so I might as well make sure its capable of doing the job. I will try and do a drawing of what i have in mind and post it on this thread for any opinions as to whether it will comply with regs
Thanks again
Ian

Am I missing something here? I've looked at the regs in the blue book and it talks about mounting feet on the legs of the main and front rollbars and on the backstays bolted to plates welded to the chassis (section1.3.2 and drawings k13 -18) I then look at the race cages on the Tiger Racing website and their cages appear to be bolted to the chassis from the outside of the body shell - Do the Tiger cages comply with the regs?
Ta
Ian

I assume so. You'd may be best to ask some of the Tiger owners that race, perhaps on the ToC forum.

As the Avon cockpit is quite narrow, I doubt there'd be any room to mount the front cage uprights inboard of the side chassis rails.

quote:

---

Originally posted by Barksavon
Thanks for the replies. 'Doctor' did you make your cage? I see you're in Derby, I'm in Ripley, would it be an option to come and have a look. I agree re the regs as I am fitting the cage for safety so I might as well make sure its capable of doing the job. I will try and do a drawing of what i have in mind and post it on this thread for any opinions as to whether it will comply with regs
Thanks again
Ian

---

OK mate ta.
Just to confuse things (for me) even more I spoke to a very pleasant chap at Mac 1 Motorsport today who told me a cage made in ERW tube (with a welded seam) is OK if the car is to be used for sprints and hillclimbs and I would only need a cage made from CDS (as per the blue book) if I want to race in such as the 750 series etc....aaargh my head hurts!!!!

You just need a rear hoop for sprints and hill climbs, mine was signed off last year, because its a little engine it did not even need the diagonal just stays. Drawing no.1 although I followed drawing no.60

Minimum Material
Cold Drawn Seamless Unalloyed Carbon Steel, containing a maximum of 0.3% of carbon.

The blue book calls for the legs to land on 3mm plates, not what the plates are fixed to. if you wanted to you could land the front hoops on bits of angle bolted into the frame although you have to consider how safe would I be?

1.3.2. Mounting of ROPS to the Bodyshell. Minimum mountings are:
1 for each leg of the main or lateral rollbar. 1 for each leg of the front rollbar.
1 for each backstay (see 1.3.3).
Each mounting foot of the front, main and lateral rollbars must include a reinforcement plate of a material of at least the same thickness as the wall of the tube to which it is being welded
(minimum 3mm).
Each mounting foot must be attached by at least three bolts, minimum M8 150 grade 8.8, on a steel reinforcement plate at least 3mm thick and of at least 120cm2 area which is welded to the bodyshell (see drawings K13 to K18). The mounting feet may alternatively be welded direct to the reinforcement plate. This does not apply to backstays (see 1.3.3).
1.3.3. Backstays. These are compulsory and must be attached near the roofline and near the top outer bends of the main rollbar on both sides of the car. They must make an angle of at least 30° with the vertical, must run rearwards and be straight and as close as possible

OK Mark cheers that's helpful. Its contrary to what the guy at mac1 said re the grade of tube so if I go the diy route will play it safe and go with CDS
Ian

[Edited on 2/4/15 by Barksavon]

If you do decide to pop round I have a couple of old copies of the MSA Blue Book if you want one.

I think there is a lot of "that will be fine" talk from some people, but having rolled a convertible (with no bar) I am a bit tetchy about all this. So if you are taking safety seriously, follow the blue book and don't skimp anywhere. My "new" car (spitfire with a zetec and dunnell efi) has a heavy rollbar with a diagonal. I am also hoping that lightning doesn't strike twice!

you want this beauty (link)

Thanks Doctor, ive downloaded a PDF of the 2015 book so i'm sorted thanks.
Seems to me that thereare various designs depending on what type of car but to comply with MSA Blue Book the cage has got to be made of CDS (and not ERW) tube.

I want the cage for the safety of my lad and myself primarily so wont be cutting any corners.

Thanks for the advice
Ian