Welding Galv Advice

  1. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    I need to weld a couple of brackets to some galvanised Unistrut. I appreciate the issues around welding galv but this will be done outside, there is not much to do, its only temporary so it doesn't have to look pretty, and I have a decent mask/filter.

    The coating of galv isn't that thick but how far back from the weld should I grind the galv coating away?

    TIA
     
  2. I would take it back at least 6mm either side of the joint and if you can, use the highest CO2 content gas you can get hold of
     
    Nick DV likes this.
  3. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    Thanks for that :thumbup: Easily go back more than 6mm but do I have to use CO2 rather than the Argon mix as I only have about a dozen very small welds? :dontknow:
     
  4. merryman Member

    Messages:
    467
    Location:
    Lancaster, England
    I used to weld galvanised stuff at work and never used anything but Argoshield. Really you want to take the min galve off that you can get away with, as it is protecting the steel. You soon know if you haven't taken enough off as you get frapping, green fire and a white sooty deposit on the weld.
     
    Hopefuldave, hunter27 and Nick DV like this.
  5. No, you’re ok with Argoshield but as I said, use a mix with the highest CO2 content you can ie if you’re using Light and you have Heavy available use the Heavy, the higher CO2 content helps to “burn” the galv out of the material
     
    Nick DV likes this.
  6. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    Thanks for this :thumbup: I'm not too bothered about taking too much galv off, as this is only temporary until around October so I'll spray it with some galv spray.
     
  7. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    Thanks for explaining :thumbup: I understand what you mean now :doh:
     
  8. bletchmonster

    bletchmonster Member

    Messages:
    447
    Location:
    Cheshire. England.
    With mig, I would grind it back in the immediate weld area until you get bright steel, a lot of folks give it a quick grind leaving smeared zinc.
    The main thing is to cover up, gloves, welding jacket etc, cos you can weld galv no problem but I associate it with pain, the spatter is evil.
     
    Nick DV likes this.
  9. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    Thanks, I'll definitely cover up :thumbup:
     
  10. Munkul Member

    Messages:
    2,109
    Cumbria, UK
    It's not as bad as the horror stories would make you think. Grind back the galv to shiny metal as said. Crack on with welding it like normal, and avoid breathing in the foul looking fumes if you get any. For a small job, it's not going to kill you if you breathe the fumes, but you will feel sick for a few hours.

    Ideally wear a gas mask or an air fed system with a gas filter, also drinking milk is supposed to help... not that I've tried it, I generally grind back and treat it like an ordinary weld.
     
    Nick DV likes this.
  11. cianh91

    cianh91 Member

    Messages:
    613
    Location:
    kildare ireland
    If it’s in an area thats awkward to grind stick weld it .

    Other wise quick clean back where the welds goin turn the welder up a bit and fire away
     
    Kent and Nick DV like this.
  12. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    Thanks :thumbup: It should be fine. I'll be welding this outside, and as I say, not much to do. Which milk - full cream or skimmed …………………………...………? :laughing::laughing::laughing:
     
  13. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    Thanks :thumbup: It's easy to get to so all being well, it'll be a quick job :dontknow:
     
  14. Wonderweaver

    Wonderweaver Member

    Messages:
    281
    Location:
    Manchester
    Have not welded galv for twenty years and happy about that --- Horrible stuff
     
    steve t and Nick DV like this.
  15. Nick DV

    Nick DV Member

    Messages:
    312
    Location:
    Southampton
    I see no reason to have to weld galv in the foreseeable future :scared: :laughing:
     
    Hopefuldave and Wonderweaver like this.
  16. Parm

    Parm Let The Games Commence

    Messages:
    11,817
    Location:
    Towcester
    Drinking milk is an old wife’s tale

    Breathing in fumes affect your lungs

    Drinking milk goes into the digestive system

    The two aren’t connected
     
    steve t, BarrieJ, skotl and 3 others like this.
  17. grim_d

    grim_d Unlikeable idiot.

    Messages:
    2,754
    Location:
    Scotland - Ayrshire
    Not a great comparison.

    There is some truth to it. Calcium intake is directly related to how much zinc (and iron, and magnesium) the body absorbs.

    Does drinking milk help with galv flu? No idea, possibly, but probably only if you drink the milk beforehand.
     
    Nick DV likes this.
  18. Parm

    Parm Let The Games Commence

    Messages:
    11,817
    Location:
    Towcester
    I'm not a dietician so cant help with minerals and iron, but drinking milk and galv flu is an old wifes tale

    This is an extract

    Metal fume fever
    Many welders report flu like symptoms after welding. The effects are often worse at the start of the working week. Metal fume fever is usually linked to welding or hot work on galvanised metals. High exposures to mild steel weld fume can also cause this illness. Metal fume fever does not usually have any lasting ill effects. Don’t believe the stories about drinking milk before welding. It does not prevent you getting metal fume fever

    From here
    http://www.hse.gov.uk/welding/illness.htm
     
    Kent and Nick DV like this.
  19. outofthefire

    outofthefire Member

    Messages:
    2,256
    Leeds
    Turn your power up a bit and just weld through it.
     
    Nick DV likes this.
  20. Kent

    Kent Member

    Messages:
    10,002
    Location:
    Bowland, Lanacshire,UK
    The milk thing is debunked now
     
    Nick DV likes this.
Advertisements