T45 & stress relief + pulse MIG welding on cages

Discussion in 'Track Prep & Tech' started by A.N. Other, Mar 13, 2011.

  1. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    447
    < split from here >

    I am confused now - I thought T45 had to be TIG welded (well, I've read that on the internet...).
     
  2. Hamish Forum Member

    Joined:
    Apr 18, 2008
    Likes Received:
    0
    T45 can be welded just like normal CDS. The cages on the wrc fiestas are all mig'd

    As for the turrets, they didn't take much work and are a better solution than using spacers ontop of the turrets to get the extra height.
     
  3. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    447
    The reason I asked was www chat about tubes having to be stress relived if MIGed due to the heat. Do you know if there's any truth in it?


    I've been busy MIG welding T45 today (offcuts, not on a cage), and it occurred to me that to get this effect of MIG blobs, you must wait a few seconds for the metal to cool before doing the next 'spot'?

    I tend to use the glow off the cooling metal, just as the auto visor tint switches back to 'normal' to sight the next spot, but doing that as quickly as I'm able, it tends to re-melt the previous and produce consecutive arcs.
     
  4. Hamish Forum Member

    Joined:
    Apr 18, 2008
    Likes Received:
    0
    Its an interesting topic for sure. I would prefer to use a continuous weld but find it incredibly hard to do on roll cage tubing as you need to be able to move your hands in 3D and your head as well to see what you are doing. Thats why I prefer to pulse weld on cages. The picture thats posted would be easy to do an continuous weld on but its when the tube turns in 2 directions it becomes very difficult!

    Both methods of welding have been tested by m-sport and were almost identical when load tested. When the cages do go in a crash they split a couple of inches from the weld. So there could be an argument for trying to keep the heat out of the tube.

    Never heard of tubes being stress relieved after welding, also not sure on the fact that tig welding puts less heat into the metal than mig? Tig is nicer as its more precise and gets the weld exactly where its needed.
     
  5. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    447
    When you're pulse welding, how long would you say it takes between each spot? Half a sec, a sec or 3-4?

    Here's some blumf on TIG on the CC site.

    It's interesting you managed to get some T45 out of them, as a lot of their kits are CDS and they're a bit reluctant to create T45 where they're not normally listed, even though in theory the tube bending/cutting/readying is the same?
     
  6. Squible Forum Member

    Joined:
    Feb 3, 2006
    Likes Received:
    5
    It wasn't the most straight forward. Took a couple of weeks of messing around. I'd only get the main hoop, a pillar bars and screen bar if I do another, as you can get them to fit nicely.

    The fitment of the main hoop is a funny one. I really like it now I know whats involved. It sits really really tightly as you can see (Well, inside the b pillars even! ). Its even almost touching the roof. Totally spot on, but I do think CC really need to have another look at the cage fitment. It sounds as if they're also wanting you to put a cross in the roof as they've supplied the tube in a number of the last few kits, although I won't be using it.

    As for the welding, there really is a lot of factors involved, but at the end of the day, it is fine to Mig, even with A18 wire if wanted, as long as the weld penetrates nicely. As Hamish says, the metal will give way before the weld when done properly.

    Been working on it again today, un picking the dash support (wish I'd decided to do it before fitting the cage!) and making up a new dash bar as the one supplied was to short for my liking. More work again tomorrow!
     
  7. Jools Forum Member

    Joined:
    Mar 4, 2008
    Likes Received:
    0
    Location:
    Plymuff
    [​IMG]

    Thats not a structural weld, thats tacking, and seeing as its a cage designed with strength being a key feature, those welds aren't good enough. There won't be sufficient penetration with the "blobs" let alone the region inbetween.
     
    Last edited: Mar 15, 2011
  8. Squible Forum Member

    Joined:
    Feb 3, 2006
    Likes Received:
    5
    Bit of an odd comment that one :lol:

    [​IMG]

    Bad picture yes, but you can still quite clearly see penetration there, which is even, done in exactly the same as above. There is no question about it, it is a structural weld.
     
  9. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    447
    It's an interesting discussion this, possibly slightly OT and I can move the it to a new thread at the OP's instructions.

    For now though, just to supply some fairly persuasive evidence that this welding style is used by folk who indeed know exactly what they are doing, one works-prepared Fiesta S1600 rally car. These were most likely M-Sport machines and I recall looking at them at the Autosport show, circa 2005/6/7:

    [​IMG]

    [​IMG]

    [​IMG]

    I'd really like to try to understand the technique used to get this effect, as it is clearly craftmen, putting pride in their work, combined with implicit and unquestioned functionality. The centre dimple marks these welds out as very individual spots, buzzed and lifted. Move 5 or 7mm, and repeat.

    The suggestion appears to be a high power setting, pull the trigger / hold it, lift, and repeat.
     
  10. mlloyd2000 Forum Member

    Joined:
    Feb 28, 2008
    Likes Received:
    0
    Location:
    Bristol
    Yep no problem with this type of welding. I've just about perfected it now and will be using it for my cage.

    As for poor penetration. You can actually get better penetration this way, by pulsing the weld you can use a higher power setting or stay in the same spot for longer. Ensuring better penetration, if continuous welding you'd most likely burn a hole through at the same power/speed.

    Here's an example of my welds.
    [​IMG]
    And the same welds from the back
    [​IMG]
    You can't argue with that penetration.
     
  11. Hamish Forum Member

    Joined:
    Apr 18, 2008
    Likes Received:
    0
    I can confirm that the welding style is used at m-sport and is being used on the brand new WRC Fiestas. Like I said earlier both types of welding were tested and both gave the same results.

    When I weld like that I do use the welder on a higher setting, than welding normally. I then pulse, pull back, move slightly and pulse again. After a while you get into a good rythm. As you can see from the pictures of the turrets and from the link VW singh posted the penetration is still spot on. I always use this type of welding on anything thin, so basically anything car based, as it keeps the heat down. Also worth noting that some of the bars in the custom cages kit were only 1mm thick, nothing like the 2.5mm the blue book states for people building there own.

    On normal runs of welding I prefer to do it continuously like so:

    [​IMG]

    However I dont have the tallent to do that whilst moving around a tube, hats off to those that can, they are far more skilled than me.
     
  12. Jools Forum Member

    Joined:
    Mar 4, 2008
    Likes Received:
    0
    Location:
    Plymuff
    I've done numerous Mig and Tig courses and at no stage did we spot weld any test pieces together, this is NOT a proper weld. Ask anyone whos a trained welder not a DIY 'er.

    An inch long smooth mig weld is roughly good for a ton on a butt weld in tension, this isn't going to be the same for some blobs stacked up. You inspect any real structural work where a Mig has been used and you will not find blobs, you'll find correct set up machine and nice consistent runs.

    I appreciate that you've seen it on cages and bits on rally/race cars but that doesn't mean its right.
    The above pictures show way more penetration than the pic i quoted way above but why didn't you just do one big run in one go?

    Tig welds usually come out as a stacked dime effect and this is just what happens from dipping filler rod into a molten pool.

    Mig should be smooth consistent welds, not tacks piled on top of each other because it was easier than setting the machine up properly.

    I agree however that thin body work, around 1.00mm it is easier to undertake the start/stop blobbing tack style but really most circumstances can be accounted for by correct set up of the machine.
    Also access can sometimes be an issue but if the torch can fit in there then do it properly.
     
  13. Jools Forum Member

    Joined:
    Mar 4, 2008
    Likes Received:
    0
    Location:
    Plymuff
    Why didn't you just use the correct set up? Get some scrap and play around untill you've got it dialed.
     
  14. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    447
    The point is these welds are being seen on 2-month old Fiesta WRC cars, built by M-Sport, which the likes of Hirvonen, Latvalla, Ostberg, Block & co are driving in the WRC right now. This is very persuasive evidence, albeit we see the weld, not the technique, so we have to reverse the technique from it.

    The Fiesta I have pictured is in the region of 5+ years old but was also prepared either by M-Sport or another contracted supplier to Ford.
     
  15. Jools Forum Member

    Joined:
    Mar 4, 2008
    Likes Received:
    0
    Location:
    Plymuff
    The age of the vehicle makes no difference its the welders in question, and i'm really surprised of the technique used to fit these strengthening parts. It's crap, they should be welded properly, its a lazy incorrect technique of welding, ask any proper qualified welder and they will tell you that style is a pikey bodge.

    (We've gone miles off topic to the members thread about their car!)
     
  16. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    447
    I'll sort the thread out, and apologies to the OP.

    Now I know you have some level of involvement with engineering, from an educational perspective I think, and I am keen to have this debate and further our collective understanding here.

    But you've used the words 'crap', 'lazy' and 'incorrect' in reference to cars which are the latest from a WRC stable. We can't get anything out of this if that's the line you take, as plainly M-Sport are not rank amateurs, yet your comments suggest they are.
     
  17. jamesa Forum Junkie

    Joined:
    Nov 8, 2003
    Likes Received:
    301
    Location:
    Abz
    I think that the difference being highlighted here is between welding for industrial (certifiable) purposes ... where items are subjected to certain testing criteria (hydro-testing / load testing / MPI / Radiography) and vehicle fabrication where there is less / if any testing ?

    Different structural requirements therefore different welding procedures ?

    Jools ... is the former what you are comparing with ?
     
    Last edited: Mar 18, 2011
  18. Squible Forum Member

    Joined:
    Feb 3, 2006
    Likes Received:
    5
    I don't think we have as you clearly think this hasn't been done right. All I can say, is the technique used here is the same as has been used on more cages (and areas of cars) than you have ever seen, which are used in a level of motorsport only a faction of cars will ever achieve. It is not 'crap', or 'lazy' and tests have been made by M-Sport themselves about this. This isn't a read fact too, as the hands that welded these has also done so for Malcom ;)

    I think you need to open you eyes a little, see beyond what your 'lectures' have told you and listen to something coming from a much bigger organisation, that have carried out investigations with a much more specific focus than any course will teach you. Do you think they just sling their cars together!? I think you need to re-acess some of your view on professional motorsport if so :lol: I'll have to forward this to some of the M-sport guys, they'll love it!
     
  19. Jools Forum Member

    Joined:
    Mar 4, 2008
    Likes Received:
    0
    Location:
    Plymuff
    Ok I see im not getting anywhere here, at the end of the day if you feel that your/friends welding is up to standard and strong enough to hold together in the event of an accident then its "fine". I however would like it to be as Jamesa has mentioned to a higher standard. Justifying the way your cage has been fitted by saying, "well thats how i've seen it done online" isn't good enough, the picture that i quoted of the door bars could have been welded up in two runs per tube, access wasn't an issue...

    You mention M-sport alot and compare your work to theirs, I know they've built some cool cars, and that their welders i guess are trained, can you show me some pics of roll cages (not additional structure work, like strut tops and reinforcement in the engine bay) where they have used this "blob/tack" style of welded to join A pillar to main hoop for example?
     
  20. Jools Forum Member

    Joined:
    Mar 4, 2008
    Likes Received:
    0
    Location:
    Plymuff
    But you've used the words 'crap', 'lazy' and 'incorrect' in reference to cars which are the latest from a WRC stable. We can't get anything out of this if that's the line you take, as plainly M-Sport are not rank amateurs, yet your comments suggest they are.

    Again this is my opinion on the work undertaken.


    I think that the difference being highlighted here is between welding for industrial (certifiable) purposes ... where items are subjected to certain testing criteria (hydro-testing / load testing / MPI / Radiography) and vehicle fabrication where there is less / if any testing ?

    Different structural requirements therefore different welding procedures ?

    Jools ... is the former what you are comparing with ?


    Cages for log booking purposes are checked visually, i think in some circumstances test pieces are undertaken and possibly tested? The welds on a cage should be of a industrial structural standard.


    I'd also be surprised if M-sport have done their own testing on welding techniques, that would be quite costly and time consuming...
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice