Silly question

  1. Snowy90

    Snowy90 Member

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    Location:
    Poor Part of Surrey
    Ok so I’m very much a beginner! My Clarke 135te came with a bottle of co2 and a crappy regulator
    I bought some 80/20argon co2 which welded ok, any way since that ran out on me I have been using the co2 and have been laying down reasonable welds.
    Due to the standard regulator leaking gas I decided to buy a better regulator and some larger bottles of 80/20 argon/co2.
    BUT exactly the same settings as I was using with CO2 and the weld is completely different, sounds more like a oxy cutter and seems really hot! I set the regulator at 4lt/min.
    Does different gas really make the difference?
    Apologies if that’s a basic question
     
  2. angellonewolf

    angellonewolf Member

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    5,238
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    bristol england
    yes there will be more along soon to help you more
     
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  3. pedrobedro

    pedrobedro Man at Matalan

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    CX Derbyshire
    I always found co2 to need more amps than argon mix, 80/20 is something like the universal mix sold by BOC for general use you might need to turn the power down a bit and find you get neater welds with less spatter.
     
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  4. RonA

    RonA specialist in repairing sealed for life equipment

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    Location:
    Stockton on Tees, UK
    I use CO2 for my welding but not by choice but on a matter of pure economics. I have used the likes of Argoshield in the past, the weld is superior in appearance with much less spatter but the cost of bottle rental & then added cost of the gas on top made it a very expensive option for a home & ergo infrequent user like myself. The costs have to some extent been addressed by the advent of the rent free bottle.
    You will get superior weld using a gas mix but the biggest change you’ll see is in the pocket.
    RonA
     
  5. Snowy90

    Snowy90 Member

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    Poor Part of Surrey
    Well that certainly would make sense as I left the settings the same. Will have to go back and do a few tests and adjust the settings.Thanks
     
  6. Snowy90

    Snowy90 Member

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    156
    Location:
    Poor Part of Surrey
    Yes especially as my welds would be ground down and it’s not overly structural work. It’s essentially some shelf brackets.
     
  7. You will need to alter your parameters to suit your gas, generally increase your voltage the higher the CO2 content, For general purpose stuff you really don’t need to go higher than around 12% CO2 content, the 20% mix is designed for heavy duty stuff where you need plenty of bite
    Main downsides with pure CO2 are increased spatter generation and you can’t weld in spray transfer, which you really want to be doing on stuff above 6mm if you can
     
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  8. Snowy90

    Snowy90 Member

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    156
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    That makes sense. im only doing thin walled 2mm box section, so as i was using co2 i guess i had it wound up too much! More practice pieces required.
    Thanks
     
  9. T0rnado69

    T0rnado69 DIY nut !!

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    Location:
    Basildon, Essex
    as a beginner, your find all sorts to weld, as many of us did when we all first started welding. and you get thru some gas..

    if you can justify a BOC hobbydeal account and argoshield light cylinder then its a good choice.
    other then using those nasty dear disposables you can get, that last a few mins.

    try a rent free cylinder option. there are a few about....


    20% is heavy...

    boc universal was (on the last cylinder i got last year) 12%
    and of course the light version at 5%
     
  10. davidjohnperry a different breed

    Messages:
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    Location:
    yate/bristol
    I always thought co2 increased the heat of mig welding hense why mag welding a being co2 a active gas. And also was led to believe that you cant get in to spray transfer with out the co2 content in the Argon.
     
  11. CO2 additions increase the “heat” of the molten weld pool thus improving fusion, penetration and deposition rates
    As you increase the CO2 level you would generally increase the voltage
    CO2 levels in mixed gases rarely exceed 25% as spatter levels will increase substantially and as said before straight CO2 and even higher levels of CO2 will not allow spray transfer.
    An arc generated under pure argon will change from globular transfer to spray at lower voltages than one using a gas with CO2 or O2 additions
     
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  12. Snowy90

    Snowy90 Member

    Messages:
    156
    Location:
    Poor Part of Surrey
    Ok so im slightly confused now!

    When i was using pure CO2 i seemed to be able to have higher power. Im using a clarke 135TE so i could have it set to 2 Max and it welded pretty good and didnt have too many blow throughs ( welding 1.5mm box section.

    Then when i switched to 80/20 CO & Argon, the weld seemed to get very hot and globular and almost fizzing rather than crackling? Ive now eased back the settings to 1Max and it seems to weld ok but still getting globular welds every now and again and blow through if i go to slow.

    Wire speed btw is set on 6.

    And gas flow at 4l/min

    Do those settings sound about right?
     
  13. davidjohnperry a different breed

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    2,172
    Location:
    yate/bristol
    That's interesting buddy I'm going have to experiment with this. The information is very useful
     
  14. Robbie260 Member

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    934
    Location:
    Scotland highland
    My supplier is highland industrial supplies probably you wouldnt get from them but check a few of your local industrial supply places, they had a deal with alabee i think ounce its now sgs, both my bottles are sgs and they are rent free have a 15ltr i belive for co2 argon and 20ltr for pure argon, to rent the bottle is a one off payment dependent on size and gas, for me it was around £150 for argon co2 mix and £185 for pure argon if i remember rightly. Then its somewhere around £65 each too have them changed for a full one.
     
  15. Munkul

    Munkul Member

    Messages:
    2,137
    Cumbria, UK
    To clarify a little more on what's already been said:

    CO2 gives more resistance to the arc, meaning more voltage required for the same amperage (wirespeed) to acheive correct arc length (bacon frying sound).

    The gas in itself doesn't give more "heat" energy, all it does is make it possible to run more voltage with the same arc length, compared to lower % CO2 mixes. Remember, the end goal is to run POWER (amps x voltage) into the joint... not into the arc, not into surrounding material, but into the joint itself - in the most efficient way possible. So "heavy" gas mixes tend to give more penetration. CO2 is an "active" gas in that it chemically reacts with the weld pool and gives certain weld puddle characteristics which I'm not smart enough to describe, but basically, on steel welds, a certain amount of CO2 is a good thing, and a small amount of O2 is even better.

    On a small welder like yours, pure CO2 will need a good chunk of available voltage just to give an acceptable welding arc and profile. You'll have lowered the wirespeed to suit.

    So when you switched to 80% argon, your voltage setting was too high, even though the amperage was similar to before. So your arc length will have been too long, wasting heat everywhere except where it is needed, giving you burn through etc.

    You may find you can run more wirespeed now, and go a little faster, which will help to eliminate burnthrough.

    You should have more flowrate of gas though - 10 l/min at least.
     
    Last edited: May 11, 2020
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  16. Nigelwade New Member

    Messages:
    12
    Location:
    New Zealand
    In my mig, I can use either, Co2,Prue Argon, or co2/argon mix. Its up to me, cost isnt a factor.

    I've run all of them. At different times, on steel. For various reasons. What I've found is.

    Co2
    Co2 pure is an excellent gas for mig welding. It's cheap, and more long lasting. For Argon, or mix, I run 15-25psi through the regulator. For co2, its 10psi, or 12psi. Firstly because the gas comes out so cold its cooling the weld as I go, and secondly, it welds nice and better at lower psi. It crackles, there is a wee bit more splatter. You really need pre, and post flow around 3-5 seconds. A more aggressive arc, and arc force, with deeper penetration. It's nice.

    Argon/Mix
    Welds nice, less splatter. Likes 15/20 psi, low pre and post flow, say 1-2 secs. But softer, gentler that pure c02.

    Argon
    I dont do this much. It's been a while. I think I ran 20psi, and that was fine. Very gentle, weld was smooth clean, and the arc super stable. Had to dial machine in, practice a bit. Works fine on steel, a bit pricey but that's no issue. Hey, its a good shield

    Helium
    Did this once for out of position up weld. Long weld series working below welding above, **** angle to weld in. Works fine, the gas travels upwards, doesn't fall away. Odd reside, leaves a yellow/brown hue. You have to wire brush that if you need to restart in an area. Likes alot of flow, so 25-30 is a starting point.

    Helium/Argon mix
    Did this for a bottle. Hard to use. Hates welding downwards. Lots of flow, 27psi seemed a sweet spot for me. Seemed to be raising away, carrying the argon with it. Had to raise current, dial feed back, and keep raising psi to find a workable ratio of all three took some practice. Not worth the cost vs hassle when co2 works just fine. Does weld very nice, sorta. Kept losing shield, but welded good when it was there. Once dialed in, I'd say if it had co2 in it, this would be an ideal mix for mig.

    My guess is, the ideal inert mig gas us probably a blend of co2 (50%), Argon (30%) and helium (20%). But, co2 works fine, just remember.. its damn cold, drop the flow, raise the current, drop the feed. Co2 welds hum like really hum, and crackle a bit/touch, when dialed in dead right,
     
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  17. Totally depends upon what material you are welding and what properties you need from the weld
     
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  18. Nigelwade New Member

    Messages:
    12
    Location:
    New Zealand
    Yep.
     
  19. Dan Evans New Member

    Messages:
    8
    Location:
    Hertfordshire
    I have the Clarke 135te and although I have only just started welding, I am getting the nice splatter sound. My gas rate is 10l/min and my wire feed is about 6 or just after.

    My gas is 5% argon but I am welding car panels so nothing thick.
     
  20. Nigelwade New Member

    Messages:
    12
    Location:
    New Zealand
    A nice trick with panel steel, to stop the panels twisting, and warping, is too....

    Soak two bits of towel, in water the wring them out until they are damp, but still quite heavy, not running with water. Place them either side of where your welding. It will stop the panels from warping. So, you can safely weld a bonnet, or boot lid, or quarter panel ... if, ... you put tack welds, every 2 inches, then repeat and fill in the gaps, until you have tack welds every 1/2 inch. You need to refresh the towels,they dry out.

    With a tig, you can just run a continuous weld at say 15amps, do the entire weld. But even then its risky.
     
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