Help with welding 15mm

  1. Adam Marshall Member

    Messages:
    324
    Location:
    Nottinghamshire England
    I have recently started renting a workshop not for welding but I am thinking of fabricating myself a few new digger buckets as I have a few sheets of 15mm left over from various projects. I have a 400amp mig hooked up to 3 phase what size wire should I use? Volts? And lastly would short circuit be ok?
     
  2. 1.0 or preferably 1.2mm wire, Argoshield Heavy, spray transfer and don’t let your beads get too big, bit of pre heat isn’t going to hurt either
     
    metalmelt and tom2207 like this.
  3. Adam Marshall Member

    Messages:
    324
    Location:
    Nottinghamshire England
    I have mig 20 gas what voltage would you be going for to get 1.2mm wire into spray?
     
  4. Don’t really do amps and volts, tend to just go by what you can see through the screen, set wire feed at around 12 m/minute and wind your volts up to suit
     
  5. dom501 Member

    Messages:
    39
    Location:
    UK, Staffordshire
    There is a job that I do that crops up every now and again 15mm to 12mm fillet (15mm base). The job specifies 1.0mm wire, I tend to set it up at around 32 volts, wire speed has to be set correctly though shouldn't be any spatter or very little
     
  6. henry Kadzielski Member

    Messages:
    871
    Location:
    Australia Wollongong
    I, myself would use 1.2mm wire also with a water cooled torch 'if you have'. The gas cooled torch will get very hot and you will get feed issues. Can't remember the wire feed, as the machine does that, but the voltage is from memory is about 35+ volts. Also no spatter and cranks it in. Also from memory it's about 380amps on the synergic setting. Can't tell you what the actual amps are as am welding so don't look at the displays. At that setting can get a almost 12mm leg length fillet on one pass, that's enough for me.
     
  7. davidjohnperry a different breed

    Messages:
    2,251
    Location:
    yate/bristol
    for 15 mm plate you run 35 + volts you will have some serious heat going in dont get me wrong I've played with our work machines at 38 volts and that was fun any way 15 mm plate in flat position run between 28 to 32 volts max wire feed speed set till its spraying with a slight or no crackle on 1.2 wire none of this weaving business. Run single beads stacked if need be so first bead no bigger then 8mm in height and then run 2 over the top no bigger than 12mm total height.
    So no to short circuit that is good for nothing smaller than 3 mm really
    Gas 75 25 or 80 20 argon co2
    1.2 er70>6 solid wire
    Volts 28-32
    Wire feed speed set by feel but try the middle of the settings and adjust on a sample plate.
    This is how I would go about it every one welds different but the information is there if you require it.
     
  8. Robert Mullins Member

    Messages:
    83
    Location:
    Salisbury, uk
    15mm plate isn't hugely heavy, if you're a tad concerned, then you could try B.O.C Coramig, it's (was?) A metal cored wire, not flux cored, but metal cored, still needing a shielding gas, and to eliminate spatter, it had to be welded using spray transfer, and with the earth positive; it is very, very hot, very fast, use a contact tip a size larger to allow for heat expansion, and position the contact tip retracted into the shroud so that it gets cooled as much as possible by the gas flow, commercial welding torches nearly always have a variety of tip, tip adapter/holder and shrouds to allow you to get the set up you require: be aware that these hugely hot, large welds have huge weld craters, be careful to fill these, as the stresses will locate any defect leading to weld failure
     
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  9. davidjohnperry a different breed

    Messages:
    2,251
    Location:
    yate/bristol
    There are loads of gas shielded flux cores on the market Lincoln elga Hobart esab murex ect they run lovely with the right settings but i guess we assumed it was solid wire plus anything over 28 volts in solid wire will be as strong
     
  10. Robert Mullins Member

    Messages:
    83
    Location:
    Salisbury, uk
    Indeed, at Appledore shipbuilders we used only solid wire, and lot's of the minor bulkheads and decks were 15mm: lots of shell plating, bulbous bows were much thicker again:
    At AMG engineering we overhauled marine dredge heads, pipework and ancillaries, the whole assembly was/is made from (ABRO) wear resistant plate and necessitated welding with BOC 'Coramig' though the company did change to a bohler thyssen wire that was effectively the same but at 1/5 of the price
    Welds layed with solid wire looked sound, but would merrily crack out along the HAZ, why, or what caused this I never enquired
     
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