Mig welding aluminium

  1. GSR New Member

    Messages:
    2
    Location:
    Kent
    Hi,
    Has anybody got any experience and advice for using aluminium wire with a mig welder?
    Plan is to be welding 3mm thick aluminium 50x25mm rhs framework?
    I’ve not got access to a tig.

    Thanks
     
  2. northwest Member

    Messages:
    732
    Location:
    Manchester UK
    I have absolutely no idea. BUT, I was just about to put up a post "Is a spool gun welding aluminium a worthwhile investment?" so hopefully we can both get the low down.

    I do know that a spool gun is almost essential to mig aluminium and you will need a bottle of pure Argon. They do seem a bit spendy though. @Hood should know the answer I think.
     
  3. Turbo Member

    Messages:
    3,371
    Location:
    Fermanagh, Northern Ireland
    I'm another who would be interested in guidance on this.

    My r-tech came with a spare teflon lined torch & roll of ally wire but the last owner admitted he couldn't get it to work properly! The fact he was using a knurled drive roller for flux core didn't help as it was marking the wire & making it harder to feed! :rolleyes:
     
  4. hotponyshoes Member

    Messages:
    1,520
    Location:
    Somerset. Uk
    I don't think a spool gun is essential at all.
    If you keep to a fairly short 3m torch it seems to work fine on most welders as long as you can keep the torch free of sharp bends.

    The bulk of the feed problems I have had seem to be due to the torch getting hot so if you are doing anything more than small amounts you might want to invest in the spool gun or a water cooled torch.
    I have seen cheap spool guns for £100 or so. Might be cheaper and more versatile than a w/c torch.

    3mm might be a bit on the thin side for a mig welder though. A pulse mig will do it no problem but they are about the same sort of money as a tig anyway.

    You will need pure argon, the correct rollers, a teflon liner and the correct size contact tips.
    I also use cylindrical rather than conical shrouds but dont think it makes a massive difference.
     
  5. wyn

    wyn Member

    Messages:
    2,994
    Location:
    Cardiff
    I've done a little bit with a kemppi 180 (2mm sheet) and a lorch m-pro 252...teflon liner, argon gas, keep the torch straight and away you go. Need to go a bit quicker with the travel speed.
     
    gordon stephenson likes this.
  6. qwakers Member

    Messages:
    123
    Location:
    cornwall, united kingdom
    every alu weld with a mig ive ever done has been brittle and has snapped when bent...
     
  7. doubleboost

    doubleboost Member

    Messages:
    2,696
    Location:
    North Easr England
    This might help



     
    stuvy, optima21 and Parm like this.
  8. GSR New Member

    Messages:
    2
    Location:
    Kent
    Thanks the advice, looks like it can be done then - it doesn’t need to be perfect, it’s a personal project rather than a paying job.
    Now I need to find a reasonably priced source of argon in Kent.
    Thanks again
     
  9. Hood

    Hood Forum Supporter

    Messages:
    9,654
    Location:
    Carnoustie, Scotland
    Spool gun not required but advisable if planning on doing it regularly.
    3mm in sheet is about the min thickness you can properly weld Aluminium with a standard Mig, with a pulse Mig you can go way down to 1mm or so. Thinner in sections can be done as the runs tend to be short and usually more material in close vicinity to soak the heat. The reason that thin stuff (sheet especially) is troublesome to weld is that for a decent Aluminium weld you want to be in spray transfer mode and thus it is way too hot for thin materials. Yes you can weld in dip transfer but the weld will not last the test of time, I have seen many failures over the years on the fishing boats and 99.999% of the time it has been because the person that welded it was using dip.

    If wanting to try then as mentioned above you want a short torch, U Groove rollers and a teflon or polyamide liner and keep the torch as straight as possible. Another thing is the contact tips for Alumium have a larger bore, they will be stamped with an A, for example 1.0A or 1.2A. You can sometimes get away with just going up a size in tip, for example if using a 1mm filler wire then use a 1.2mm tip but it would be better to get the correct 1.2A tip.
     
    Last edited: Dec 16, 2019
  10. stuvy

    stuvy Member

    Can you post some pics up please I haven’t spool gun welded in years
     
  11. Hood

    Hood Forum Supporter

    Messages:
    9,654
    Location:
    Carnoustie, Scotland
    Me?
    Pics of?
     
  12. stuvy

    stuvy Member

    @Hood yes please mate

    Plus others I’m tempted to buy a spool gun, what’s it like to sand smooth as in a car panel?
     
  13. Hood

    Hood Forum Supporter

    Messages:
    9,654
    Location:
    Carnoustie, Scotland
    Not used a spool gun for a few years now. I now have pulse Mig welders (EWM Phoenix 330 and 355) and I use a push pull.
    I think the last welds I did with the spool gun will be in the R-Tech section as I was using that with the spool gun.
     
    stuvy likes this.
  14. Hood

    Hood Forum Supporter

    Messages:
    9,654
    Location:
    Carnoustie, Scotland
  15. stuvy

    stuvy Member

    @Hood thank you mate
     
  16. 500e

    500e Always buy fire insurance a flood is hard to start

    Messages:
    4,060
    Location:
    SWest UK
    Hood any help with what voltage \ wire speed would you use for 4mm alloy in spray mode please
     
  17. Hood

    Hood Forum Supporter

    Messages:
    9,654
    Location:
    Carnoustie, Scotland
    Oh man now you are asking, all previous welders I had for doing Alu prior to the R-Tech didn't have voltage readouts so it was just a case of finding the sweet spot on each and likewise with the wire feed, just adjust until it was humming away.
    The R-Tech did have readouts for both but it was a few years ago now and I can't really remember but I would say around 24v and maybe 10m/min sort of way. That is just a guess though as I can't really remember.
    With the pulse Migs they are synergic so once I have set up the parameters to my liking I just adjust the wire feed on the push pull and voltages etc change and I don't pay attention to what they are.
     
    500e likes this.
  18. doubleboost

    doubleboost Member

    Messages:
    2,696
    Location:
    North Easr England
    Spool gun video



     
    stuvy and Hood like this.
  19. Hood

    Hood Forum Supporter

    Messages:
    9,654
    Location:
    Carnoustie, Scotland
    500e likes this.
  20. Turbo Member

    Messages:
    3,371
    Location:
    Fermanagh, Northern Ireland
    Thanks John, that first video has shown me how to set my welder up for ally welding & it's not the way the last owner had it set up! :rolleyes: The second one has great tips on using it, I'll have to have a go trying to use mine for ally. :thumbup:
     
Advertisements