Question about roll cage!

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Hi guys i help my cousin with his roll cage and I would like to know the requirements to weld  roll cages professionally thanks in advance Mike
Reply:Oh god...  What SFI spec are you under?  If you can't answer that, you have no business even touching this. Originally Posted by SundownIIIDon't get me wrong.  They are just as ill informed about politics as they are about welding, they just post more on that subject.
Reply:OMG here we go again!!!VLast edited by Vinnie; 01-04-2012 at 10:59 PM.
Reply:Here we go again is right.  Keep in mind that many new welders come in these forums asking questions about building roll cages (favorite starting project).A roll cage is a difficult first project.1) Designing one - you hit on the first requirement... sort of.  Every type of sanctioned racing association has a specification for safety equipment and roll cages are a very common one.  You need to understand the written letter of the rules and also understand what the inspectors of said safety equipment will allow and not allow.  Sucks to build a cage, show up at the track, and then be sent home.   Even if you aren't building one for sanctioned racing, you could probably find some form of racing that parallels what you are doing and follow those guidelines anyway.Even if you buy a kit (which is typically two hoops and a lot of straight pieces) there is still a lot of gray area which if you make the wrong choices will send you home.2) Building one - you need to be able to accurately cut and bend tubing - and make sure you do it in such away that you are following all the rules you leaned about in step 1.  You need to be able to weld in all positions - both your body position and angles of the welding equipment.   The welds need to be sound (duh) and look sound (because of the inspectors).3) Getting it through inspection.  As part of your research (step 1) you will find that all the sanctioning bodies have rules about inspecting.  Most sanctioning bodies don't want the cage painted because it interferes with inspection.  Some cages need to be certified (inspected well before an event).Finally, and this should be the most sobering part.  Roll cages are indeed a safety device.  If your are doing something that requires a rollcage, you have to assume its inherently dangerous and with 3000+lbs of steel moving at 50+mph someone could easily die.  Even if you and your cousin have some sort of understanding, if for example the roll cage fails and your cousin dies as a result (or even if would have died anyway) do you think his wife/parents/SO/life insurance company or whomever is going to be sympathetic to you when it comes time to figure out who will pay for what?  If you compete in a competitive motorsport event, they make you sign a waiver that you, or your survivors will not sue the organizers or the people that work for them etc. etc. etc.  They never mention the car builder.Consider that dedicated race car fabrication shops will sometimes charge as little as $1000 for a roll bar and $2000 for a cage, you have to ask if this is even worth it.And please don't say its just for show.  The last thing you want inside a car is a piece of metal that can come loose and bop you in the head or break and spear you in the chest.  Not to mention the extra 100 lbs will make the car slower.Finally, consider this.  I have seen many 'project' roll cages built by amateurs.  Usually its a project car, didn't get finished etc.   Say its a $1000 car body, with a cage in it.  One look at the welds and you can see it was done with cheap, Home Depot style welder by a relatively unskilled weldor.   And here's the kicker, they want $500 more, because it has a cage in it.  I offer $500 less, because I need to cut the POS out.Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:Circle track guys, (Especially street stock, pure street, super street, etc.  Anything entry level really.) are notorious for absolutely crap cages.  I mean horrid things.  I picked up a car the other week to pull the motor out of.  I cut the cage out and just cut it down into sections to reuse the steel.  Not even DOM or any type of Chromoly.  ACKKK!!!  I'll get some pics of a "bad cage" this weekend. Originally Posted by SundownIIIDon't get me wrong.  They are just as ill informed about politics as they are about welding, they just post more on that subject.
Reply:Originally Posted by T1000I would like to know the requirements to weld  roll cages professionally
Reply:Question: If I use EMT tubing to build my roll cage, will my 90A 110V Harbor Freight flux core welder handle it?
Reply:Originally Posted by KelvinQuestion: If I use EMT tubing to build my roll cage, will my 90A 110V Harbor Freight flux core welder handle it?
Reply:Originally Posted by KelvinQuestion: If I use EMT tubing to build my roll cage, will my 90A 110V Harbor Freight flux core welder handle it?
Reply:Originally Posted by jmtebbensCircle track guys, (Especially street stock, pure street, super street, etc.  Anything entry level really.) are notorious for absolutely crap cages.  I mean horrid things.  I picked up a car the other week to pull the motor out of.  I cut the cage out and just cut it down into sections to reuse the steel.  Not even DOM or any type of Chromoly.  ACKKK!!!  I'll get some pics of a "bad cage" this weekend.
Reply:Originally Posted by GambleI've never heard of anyone welding a cage with flux.
Reply:Originally Posted by lamenameHe was being humorous.......I hope.
Reply:Another candidate for the Darwin award?Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by GambleI've never heard of anyone welding a cage with flux.
Reply:first thing you need to do is go buy an up to date nhra rule book and find a quiet room and read the section concerning roll bars and cages..  One of the first things stated in the rulebook is your not suppose to use any type of fluxcore or arc welding, they state mig (non-fluxcore) and or tig only..tackleexperts.comwww.necessityjigs.comhttps://www.facebook.com/groups/mach...dingequipment/
Reply:Originally Posted by KelvinWould solder be better? I have the lead-free type.
Reply:you don't need the gorilla glue if you reinforce the joints with Popsicle sticks and wrap the whole cage with gorilla tape.225NT bobcatAEAD200LEScott 125mm175, mm252 w 30A, PT225mm211, TA 181iHyper Therm 380, cut master 529100X & XX, Digital Elite6 Victor setssmith little torch, meco midget kalamazoo band sawsteel max saw evoulution circular saw
Reply:You can do what this guy did and just shove a bar in the car and put wood screws so it doesn't move around.http://www.clubintegra.com/board/sho...t=64261&page=3Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:i hope for safety sake he used loctite on the threads. if not i ain't ridin in that car225NT bobcatAEAD200LEScott 125mm175, mm252 w 30A, PT225mm211, TA 181iHyper Therm 380, cut master 529100X & XX, Digital Elite6 Victor setssmith little torch, meco midget kalamazoo band sawsteel max saw evoulution circular saw
Reply:If yer welds look like poo, just give em a smear of silicon to smooth them out to pass tech.A friend of mine did.I dont ride in that car anymore..............
Reply:Originally Posted by LarryOIf yer welds look like poo, just give em a smear of silicon to smooth them out to pass tech.A friend of mine did.I dont ride in that car anymore..............
Reply:note to self, never trust a roll cage I didn't build myself. that said. I have no intetion of needing to build a rollcage in the next 15+ years so...There are no problems. There are only solutions. It's your duty to determine the right one.Hobart Handler 210Airco 225 Amp MSM Stinger
Reply:Originally Posted by KelvinQuestion: If I use EMT tubing to build my roll cage, will my 90A 110V Harbor Freight flux core welder handle it?
Reply:Originally Posted by zapsterYou can't paint any cage until you get it inspected and the tag is attached......zap!
Reply:Here is a cage that shows some good examples of poor quality.  I bought the car this was in for the motor and I cut this out of it.  Just a couple of quick pictures.  I cut this one side out and all the pics are from this section.I really like the piece of filler hanging in the weld...Nice looking joint here.I think they forgot to finish welding this joint even.Here is frame attachment point.  Not the correct way to do this.Keep in mind, this car ran for five years and never was even questioned during a tech inspection... Originally Posted by SundownIIIDon't get me wrong.  They are just as ill informed about politics as they are about welding, they just post more on that subject.Well the tech inspectors need a slap.Unbelievable!...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Ahhh...  It's not their fault.  Half of these guys can't count to 20 without removing their shoes.  These are circle track guys afterall. Originally Posted by SundownIIIDon't get me wrong.  They are just as ill informed about politics as they are about welding, they just post more on that subject.
Reply:Originally Posted by jmtebbensAhhh...  It's not their fault.  Half of these guys can't count to 20 without removing their shoes.  These are circle track guys afterall.
Reply:Originally Posted by jmtebbensAhhh...  It's not their fault.  Half of these guys can't count to 20 without removing their shoes.  These are circle track guys afterall.
Reply:In their defense, these are short little bull rings and very entry level stuff.  350 CFM carb limits, claimer motors and trans, spec everything.  I don't think there is anyway to actually have a full out cage professionally built on these budgets.  I mean, the rolling chassis only costs around $5k "new".  These aren't super fast cars, and I don't think I've seen them much over 60 MPH and I've never seen one go rubber side up.Still not acceptable, but it is what it is. Originally Posted by SundownIIIDon't get me wrong.  They are just as ill informed about politics as they are about welding, they just post more on that subject.
Reply:I have seen people killed in much better at a slower speed..There is NO excuse for stuff like that...Sorry....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by zapsterI have seen people killed in much better at a slower speed..There is NO excuse for stuff like that...Sorry....zap!
Reply:Originally Posted by zapsterI have seen people killed in much better at a slower speed..There is NO excuse for stuff like that...Sorry....zap!
Reply:A lot of sarcasm and whatnot going through this thread but I have a serious question.I would like to become proficient in welding safety structures, roll cages included. For those who are good how did you get get practice and how did you inspect your welds to check your progress?
Reply:Originally Posted by canyon289A lot of sarcasm and whatnot going through this thread but I have a serious question.I would like to become proficient in welding safety structures, roll cages included. For those who are good how did you get get practice and how did you inspect your welds to check your progress?
Reply:Outside of welding for gas compaines I used to build/repair sprint car frames. All were out of Moly, and I did build a few street stocker roll cages as well. All were welded with GTAW 100% Argon. There has been some good advice along with the sarcasim and I feel there is one area that has not been touched on in this thread concerning roll cage fabrication, fitup. A good quaility tubing notcher is a must, torch cutting is not advisable. Didnt say it couldnt be done, not the preferred method. Weld widths and thicknesses effect the amount of residual stresses that the weld joint will have after welding. The more residual stress the more likely cracking will occur, or failure when subjected to loading (roll over). A small gap is good but a big gap is not......there is a fine line as to what is acceptable. Welding piping and other structures that have welding procedures and governing codes ect cover all of the min and max allowed variables, root openings, weld profile, weld width, ect. However, roll cages in all of the sanctions that I have been involved with do not go into that type of detail, on the amature level. I am sure NASCAR/NHRA might touch on design and production details in the professional classes. Just my 2 cents.....A young green pipe welder asked an old salt one day...How can I make the weld on the bottom of the pipe look like the top.......The old salt replied....Screw up the top......
Reply:My general rule of thumb is the fit up needs to be tighter than the filler being used.  So if I'm TIG'ing up a cage, I will stay with under a 3/32" gap on the joints.  That is a tight fit up.  A hammer has absolutely no place in fabbing a rollcage.  You know how a lot of welding is dirty, sweaty, smash it, grind it, jam it, burn it in type of stuff?  This is not that at all.  Cage building is, in my opinion, one of the most stressful types of welding.  I know that what I'm building is going to be beat to hell and if it fails that someone may very well die.  That is stressful to me.It is important to have a lot of room and at least one helper.  The tubes should effortlessly slip into place and be fit tight enough that they almost hold themselves in place.  If they don't, you're not ready to weld yet.  All the good prep work and "Zap style" welding still won't overcome a poorly designed cage.  It is a bit trickier than one would imagine.  I recommend leaving this one to a professional race shop.  I'm not even going to do the cage on my own hotrod, just isn't worth the time and effort.  I'd rather pay someone else and that is not something I say often. Originally Posted by SundownIIIDon't get me wrong.  They are just as ill informed about politics as they are about welding, they just post more on that subject.
Reply:It's not just the welding. There's all the geometry that goes into building a proper cage too. The picture from the last page of the cage part the poster had cut out showed tubes being welded on in the middle of a span. Unless that was for some sort of triangulation, the tube would bend when hit. Look at proper roll cages in professional vehicles. Some of them are a work of art and you can tell an engineer did his homework.
Reply:Originally Posted by ttyR2It's not just the welding. There's all the geometry that goes into building a proper cage too. The picture from the last page of the cage part the poster had cut out showed tubes being welded on in the middle of a span. Unless that was for some sort of triangulation, the tube would bend when hit. Look at proper roll cages in professional vehicles. Some of them are a work of art and you can tell an engineer did his homework.
Reply:If you are tig welding a cage, you better have essentially "perfect" fitup. Mig is a bit more forgiving with this, but either way better fitup means a stronger joint and a better weld.. That is the hardest part about building a cage. Having everything fit nicely, and thinking ahead to how you can weld the joint al the way around.. From making holes in the floor to drop the cage down to weld the tops to cutting off the roof, make sure your cage is welded all the way around! Cutting the roof off is a bit more... involved HTP Invertig 201Lincoln Idealarc SP250Miller 180 AC StickBy farmall:They should have held the seagull closer to the work, squeezing evenly for best deposition.