roll cage help

[welder_one]

i got called to this fellows house to see about welding a roll cage into a spec miata. i shot him a price and he said i was way too high. i said that the tig process was slow and i would have to spend more time on it than if i were to mig. he then showed me a bulletin where the tig and stick processes were not recomended for welding these cages. why would that be? i would think you would want a crash cage to be tig welded. to know that every weld is good, not get cold laps or cold starts. anyone have any info on this? please help

[Jetmekdc-10]

Roll Cage

Just Curious, What was he wanting the cage made from?

[welder_one]

the cage is almost a prefab deal. the pieces are cut and bent all that has to be done is the fishmouth and the welding. i didnt look at the size real close but it looked about 1 inch to 1 1/2 inches d.o.m. tubing 95 wall.

[dabar39]

roll cage

welder_one, I don't know much about the spec Miata series, but all roll cages should be 1 3/4" x .095 tubing for the main cage and the front and rear hoops can be made from 1 1/2" x ,063 tube. Once again, I don't know much about the SCCA requirements but most rule books for most classes will say that the cage be constructed by continuous electric weldment, they do not specify which type of weld but mig is most common. try this link and see what info you can get from them. http://www.specmiata.com/


One more thing, I don't doubt your welding ability, but, roll cages should be left to some one who has specific knowledge of cage construction. One misplaced bar or poorly engineered construction can lead to serious injury or death.


If you don't believe me just look at the photo in my signature, John was in a very safe, well prepared car and he still died in it. His case was more of a freak accident but the risk of injury or death is always there.Dave

[fun4now]

if he ordered a prefab kit i would contact the maker to see why they don't want TIG?? seems odd to me also. dabar39 seems to know about some cages for shore good advice. i wonder if its a cheepo comp. that want you to use MIG due to pore fit-up ?? too many big gaps for a good TIG weld.
you might try them over on the ask andy side, i know Andy builds card and cages for nascar i think it is. i can see if i can find his e-mail if you don't get a response. i have herd of MIG not being allowed but never not TIG ?? let us know what you find out.

[wireburner]

welder-one did you find out why ? , I have helped my cuz build 4 or 5 cages for Ford boncoas , dirt late model ,zuki samurai, we tigged the late model cage and miged the other ones

[welder_one]

well i took a closer look at the tubing and it is 1 3/4 0.95 wall, sorry about that. i did ask another fellow that i know that builds dirt track cars and he said that they are starting to recommend a mig weld b/c they are getting alot of "do it yourselfers" now and a tig weld is harder than mig and harder than stick too. not as easy to mess up they say. well i turned down the job anyway b/c the guy still doesnt want me to tig the cage and i dont want the liability. all of my certs are with aluminum anyways. but i really do appreciate the help guys...

[jamscal]

Stick isn't acceptable for an SCCA cage, tig is.

They also have tubing sizes based on the weight of the car. 1.5 x .120 I think is the minimum for production based cars.

I don't know where he could have got the 'bulletin' I'd like to know about it.

Here is the General Competition Rules for the SCCA:

http://www.scca.com/_FileLibrary/File/GCR2007.pdf

FWIW, I think they get from 900-1200 to build (bend, cut, notch, fit) and install (weld) a decent cage. That's probably mig, but I'll bet he has that number in his head (And he's already paid for the cage.

-James

[man of steel]

re roll cage

was the bulletin printed on toilet paper? Tig is the cleanest and strongest type available.some motorsports go with mig but when the welds are critical, tig all the way baby

[fun4now]

so they recommend you use MIG cuzz they think you suck at welding. thats just nuts. if you suck at welding you should be getting told to have some one else do it, not "go with the one thats easy to make look good". what are they thinking giving advice or instructions like that?? i guess that explains the welds on the bronco cage we saw in the other post.
i was just joking when i said it was because they did a bad job of fit up, but i guess they expect a bad weld any way so whats fit up matter.

[wireburner]

so they recommend you use MIG cuzz they think you suck at welding. thats just nuts. if you suck at welding you should be getting told to have some one else do it, not "go with the one thats easy to make look good". what are they thinking giving advice or instructions like that?? i guess that explains the welds on the bronco cage we saw in the other post.
i was just joking when i said it was because they did a bad job of fit up, but i guess they expect a bad weld any way so whats fit up matter.

they must of thought the paint would coverit up , ..................
I have bad news for them it didn`t