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  • HAWK
    replied
    INTP,

    Even though I witnessed this spray/glob transfer alternating between states I would not recommend it. The heat was there, but the appearance was poor due to many variables. I am sure the high co2 content being a large contributing factor. I firmly believe in and use 92%argon/8%co2 for short arc and spray on mild steel. I rarely use c25 except for testing as most GMAW machines are tested with and rated by c25 gas.

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  • INTP
    replied
    I find the two examples of spray given by Dan and HAWK to be interesting. In both cases, they illustrate exceptions to the "rules" that I've seen stated. Experience trumps theory, it seems, and the numbers don't seem as fixed as I had once thought. I admit to never having tried spray with C25, but have relied on what I read.

    But even the theory is a little vague. For example, in Miller's GMAW book, it states (somewhat less than definitively) "With CO2 contents below 10%, the arc transfer will be stable spray transfer on steel similar to an argon-oxygen mixture. Too much CO2 in the mixture will produce a globular transfer." (p. 66)

    Esab says 15%:
    http://www.esabna.com/EUWeb/MIG_handbook/592mig1_7.htm

    In this Lincoln FAQ, it indicates that 85/15 can be used for spray transfer:
    http://www.lincolnelectric.com/knowl....asp#question2

    Thanks for the feedback.

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  • HAWK
    replied
    farnmboy,

    When I learned the MIG process I was taught push and pull methods of manipulating the torch. After many years of use and a lot of aluminum I only push the torch.Aluminum pretty much requires the push method to achieve a good sound weld. It is true the push method can reduce penetration and I compensate for that by increasing the amperage/wire speed. With 400+ amps I only occassionally run out of the power I need to do a job. However, it does happen and I have to take my project into my buddies shop. I have never seen anything his shop could not weld with 1000 amps output.

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  • HAWK
    replied
    Originally posted by INTP
    Even with the power available from the MM251, for mild steel, you need less than 10% CO2 to get spray transfer. Above that and you're likely to get globular transfer.
    INTP,

    I saw a machine achieve sporadic spray with .035 wire and C25 at 400 amps. It cycled between glob trans and spray arc. It was at best an ugly weld. The operator was trying to finish a spray project with 1/2" plate and ran out of 92%ar/8%co2. The unit was a Miller XMT 304 running wide open.

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  • cope
    replied
    Originally posted by Dan
    Alan,

    I wouldn't recommend running an .035 solid wire for very long at a wirespeed setting of 70, because more then likely this is past the machine rated 210 amp output. At about 65 on the wire speed dial with an .035 solid wire, my unit is outputting around 205 to 210 amps. At a wire speed setting of 70 you could potential be up in the 220 to 230+ amp range Just fine for my MM 251, but not for our MM 210s

    Dan,,Where di you set your 210 for .035 spray?

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  • Danny
    replied
    Originally posted by cope
    90/10 with .035 wire 1/4" 7/70 and it welds like a house on fire. I need some heavier gloves if I'm going to make a habit out of this. I am going to dig around in the shed and see if there's anything 1/4' buried there to try with the .030.

    Alan,

    I wouldn't recommend running an .035 solid wire for very long at a wirespeed setting of 70, because more then likely this is past the machine rated 210 amp output. At about 65 on the wire speed dial with an .035 solid wire, my unit is outputting around 205 to 210 amps. At a wire speed setting of 70 you could potential be up in the 220 to 230+ amp range Just fine for my MM 251, but not for our MM 210s

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  • cope
    replied
    Originally posted by Dan
    Alan,

    Just hook up the bottle of 90/10 to your 210 and try it out on some of the scrap that you've been short arcing on. Doing this, well at least answer your question whether or not the 90/10 will work for you. or not t
    90/10 with .035 wire 1/4" 7/70 and it welds like a house on fire. I need some heavier gloves if I'm going to make a habit out of this. I am going to dig around in the shed and see if there's anything 1/4' buried there to try with the .030.

    Leave a comment:


  • Danny
    replied
    Alan,

    Just hook up the bottle of 90/10 to your 210 and try it out on some of the scrap that you've been short arcing on. Doing this, well at least answer your question whether or not the 90/10 will work for you. or not t

    Leave a comment:


  • cope
    replied
    Originally posted by Dan
    Alan,

    Your 210 should spray arc an .030 with the 90/10. I got mine to spray arc an .035 with 90/10, but not to the same arc intensity level that I can with 98/2. I don t know how much your 225 volt input is going to rob from you in the area of out put voltage on tap#7. My input voltage is 240 volts +, and at around 200 to 210 amps my machine outputs around 25 volts on tap #7. So, since my unit might potential output a higher voltage then yours on tap#7 you might not have the same success as me with the .035 and 90/10. However, since an .030 transitions over to spray at a lower level then the .035 I think you 'll be fine with the .030. Just set the machine to tap #7 and around 80 on the wire speed (.030 wire) to start and adjust the wire from there.


    As far as spray gases go, my local supplier only carries 98/2oxy, 95/5oxy, 90/10 co2, and 85/15 co2, so thwere the only gases that i m familiar with. For your MM 210 out of these, 98/2 would be my recommendation, it is a very easy gas mix to tune the spray arc in with, and produce spatter free welds.
    Dan, Thanks. I ran some beads today on 1/4" stock using .035 and 4/40 and got excellent penetration and good looking beads. My 210 doesn't like you to start a weld w/o clipping the wire; it makes a loud snap then settles in to the arc. I nee to get some more steel and try out spray.

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  • Danny
    replied
    Originally posted by cope
    Dan,

    You have mentioned recently that you felt the MM 210 could not handle 90/10 for spray. I have not tried it , but I do have a full cylinder and want to at least give it a try. I don't remember what other options the dealer has. Is there another Ar/CO2 blend that would work or do you recommend 98/2 Ar/O2?

    Alan,

    Your 210 should spray arc an .030 with the 90/10. I got mine to spray arc an .035 with 90/10, but not to the same arc intensity level that I can with 98/2. I don t know how much your 225 volt input is going to rob from you in the area of out put voltage on tap#7. My input voltage is 240 volts +, and at around 200 to 210 amps my machine outputs around 25 volts on tap #7. So, since my unit might potential output a higher voltage then yours on tap#7 you might not have the same success as me with the .035 and 90/10. However, since an .030 transitions over to spray at a lower level then the .035 I think you 'll be fine with the .030. Just set the machine to tap #7 and around 80 on the wire speed (.030 wire) to start and adjust the wire from there.


    As far as spray gases go, my local supplier only carries 98/2oxy, 95/5oxy, 90/10 co2, and 85/15 co2, so they're the only gas mixes that i m familiar with. For your MM 210, out of these, 98/2 would be my recommendation, it is a very easy gas mix to tune the spray arc in with, and produce spatter free welds.

    Leave a comment:


  • cope
    replied
    Originally posted by Dan
    So, I guess i should admend my previous statement, and state that my true recommendation would be 90/10co2 and 98/2 oxy.
    Dan,

    You have mentioned recently that you felt the MM 210 could not handle 90/10 for spray. I have not tried it , but I do have a full cylinder and want to at least give it a try. I don't remember what other options the dealer has. Is there another Ar/CO2 blend that would work or do you recommend 98/2 Ar/O2?

    Leave a comment:


  • Danny
    replied
    Originally posted by Scott V
    Dan,
    I never used 95/5 but isn't the puddle a little wet for manual mig welding? They use that gas up here for some machine type spray-arc welding.

    Scott personally, I wouldn t use the 95/5 because of the high level of oxygen in the mix. I just figured i better mention it because someone else would probably mention that it was a possible gas mix. So, I guess i should admend my previous statement, and state that my true recommendation would be 90/10co2 and 98/2 oxy. As far as the puddle being wet, you should know that we can control how the weld puddle wets out by regulating the arc length. Also placing the part in a flat position pretty much eliminates any undercutting problem. A tight arc length on horizontal fillets should control under cutting on them too.

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  • Scott V
    replied
    Originally posted by Dan
    The MM 251 has no problem spray arcing 90/10 Co2 with an .035 wire. Believe it or not, it is also capable of producing a lower level spray transfer (spatter free) using C-25 with an .035. with the C-25, you have to max the voltage out, which is 29.5 volts on my unit. Not a spray transfer approach that i recommend just wanted to test the units potential. 90/10, 98/2, or 95/5 would be my recommendation for spray transfer gases with the MM 251.
    Dan,
    I never used 95/5 but isn't the puddle a little wet for manual mig welding? They use that gas up here for some machine type spray-arc welding.

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  • Danny
    replied
    Originally posted by INTP
    Even with the power available from the MM251, for mild steel, you need less than 10% CO2 to get spray transfer. Above that and you're likely to get globular transfer.
    The MM 251 has no problem spray arcing 90/10 Co2 with an .035 wire. Believe it or not, it is also capable of producing a lower level spray transfer (spatter free) using C-25 with an .035. with the C-25, you have to max the voltage out, which is 29.5 volts on my unit. Not a spray transfer approach that i recommend just wanted to test the units potential. 90/10, 98/2, or 95/5 would be my recommendation for spray transfer gases with the MM 251.

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  • Paul Seaman
    replied
    I was speaking off the top of my head and you've got me curious so I went back to the book. It says 98Ar-2O2 with .035 or .045 wire. I do appologize for the error.

    The book also gives the transition amps required to transition from short arc to spray on .035 wire as 165 amps and .045 wire as 220 amps.

    Peace,

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