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Scrutineers - Roll cage stress calculations
Terrapin_racing - 21/5/04 at 10:38 AM

Scrutineers - Roll cage stress calculations

Anyone had any experience with scrutineers requiring stress calculations on home made roll cages?
cheers
Rob


Terrapin_racing - 24/5/04 at 08:34 AM

Come on guy's some of you locost racers must have discussed roll hoops for msa cert. What do the scrutineers say?

Rob


Cita - 24/5/04 at 09:07 AM

Put your thumb into the air Rob and suck as much as you can out of it and put this on paper.It works for politicians so it should work for scruteneers.
It's obvious that nobody seems to have a clue what is needed(i most certainly havn't) so being this the case it's probably not that fussy at all.
Not much of a help but wish you all the best


Terrapin_racing - 24/5/04 at 09:58 AM

I think your right! Chassis looks good - any further progress?


timf - 24/5/04 at 10:26 AM

terapin have you tried calling the msa directly, most of the scrutineers, me included won't allow a non certified caged car to runand will refer the compeditor to the msa technical section.


Tim


imull - 5/6/04 at 10:14 PM

you are not allowed to compete in the UK without a certified rollcage. Altering a approved design is specifically banned unil it is sujected to the relevant testing as a new design!!!.

If you made it to the blur book dimensions then it is a case of proving wall thickness and assuming the welding is of a decent standard (ie no bird shit welding) then they will certify it.

If you choose to go another way and use other materials that will allow you to use a ligher material (eg T45) then you will need to submit the designs to the MSA for approval.

They will then be sent for analysis by an approved institution afaik. They might also be changing the rules to ask for a test cage too for a physical test but not too sure on this score.

Surely for Locost racing you have to use a standard cage anyway?


Terrapin_racing - 7/6/04 at 09:13 AM

2 weeks now and no response from MSA tech guy - must call him today.
I've actually exceeded the spec by using 4mm cold drawn seemless tube and the welding is industry standard (I trained in the oil industry).
I am bemused by the number of manufacturers selling locost roll bars - are they all approved/tested? I wonder??


timf - 7/6/04 at 09:29 AM

quote:
Originally posted by Terrapin_racing
I am bemused by the number of manufacturers selling locost roll bars - are they all approved/tested? I wonder??


if its like a certain diahatsu charade gti cage i once look at then no the cage had a cert no on it but something didn't add up so i rung the cert no into msa and it came back as an escort mk2 cage.
the owner had cut a section out of a safty devices cage and joined into his own.


Terrapin_racing - 7/6/04 at 10:31 AM

Rang MSA - they have my e-mail of 25th May and are looking at it but are not sure of the answer??? Advised that I'll get a call sometime today - keep you posted


andyps - 8/6/04 at 11:17 AM

I was at Harewood Hillclimb on Sunday and there was a great looking Minor 1000 convertible competing - in reality it was a spaceframe built car with a Fiat twin cam engine front-mid mounted, driver practically sat in the back - very complete roll cage in it.

When I was in the paddock looking at it at lunchtime the driver was talking to the scrutineers about his eligibility for future events, and whilst I didn't hear all the conversation the scrutineers were saying that they did not know of a scrutineer in the country who would test a cage. Even though he had certification from the designers and builders of the cage they seemed to be wanting an MSA check, but didn't know how he couls get it. The name which was mentioned at the MSA was John Simons (it think).

Please don't take any of this as absolute fact, it is just from some things I overheard.

Good luck with your request to MSA.


Terrapin_racing - 8/6/04 at 01:17 PM

Yes, it would be John Beardsmore in his Fiat twin cam Minor. John and I are regularly in conversation over this. He has just got his log book after a long drawn out saga of producing all his own stress calcs etc.
I believe I will not have the same issue with a single seater roll hoop.


andyps - 8/6/04 at 02:44 PM

It was John - great looking machine he has built!


imull - 9/6/04 at 04:41 PM

quote:
Originally posted by andyps
The name which was mentioned at the MSA was John Simons (it think).



The guy is called John Syme. He has a deputy called John Ryan with whom I have dealt with a fair bit. They ar a bit hard to get a hold of but both seem fairly decent...

The trouble with Ivory Towers is that they change their mind more times than you would think possible


Wingnut - 21/6/04 at 11:17 AM

quote:
Originally posted by imull
you are not allowed to compete in the UK without a certified rollcage. Altering a approved design is specifically banned unil it is sujected to the relevant testing as a new design!!!.



Please correct me if I'm wrong here, but I read the blue book with the understanding that there are *default* rollcage designs (different regs for different disciplines) and long as the cage is built to a default design, no certification is needed ??