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  • spray welding

    i was hoping some of the experts here could explain "spray arc welding". what is it? how is it done? what type equipment is used? maybe i am way behind the times, but all i ever used was flux core wire welding and plain ol' arc stick welding. is the spray welding a lot better, cheaper or faster? is it something that the occasional home hobby welder would want?

  • #2
    Re: spray welding

    Originally posted by haybine
    i was hoping some of the experts here could explain "spray arc welding". what is it? how is it done? what type equipment is used? maybe i am way behind the times, but all i ever used was flux core wire welding and plain ol' arc stick welding. is the spray welding a lot better, cheaper or faster? is it something that the occasional home hobby welder would want?
    A lot has been said here on spray arc welding....go to search and plug in "spray arc" and you will get pictures and a full explanation of the process...you would need minimal 250 amp machine....more amps, hotter, faster...not for the hobbyist.
    Last edited by Rocky D; 10-24-2002, 06:59 AM.

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    • #3
      HAYBINE.............TON'S OF INFO IN THE OLD WEB SITE AND SOME HERE.....IF YOU WERE USEING SPRAY ARC TRANSFER WITH CO 2 IT WOULD BE CALLED GLOBULAR TRANSFER ON STEELS............. DOES THAT HELP EXPLAIN IT A LITTLE BETTER......ROCK
      [email protected]

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      • #4
        Re: spray welding

        Originally posted by haybine
        i was hoping some of the experts here could explain "spray arc welding". what is it? how is it done? what type equipment is used? maybe i am way behind the times, but all i ever used was flux core wire welding and plain ol' arc stick welding. is the spray welding a lot better, cheaper or faster? is it something that the occasional home hobby welder would want?
        Spray transfer is a high voltage and high wire speed process. Uses a solid wire. Requires an argon rich shielding gas. I was taught that the mixture must be at least 90% argon and the remainder is either oxygen or CO2. Oxygen content should never be more than 5%. The gas that I use is 98% argon/ 2% oxygen. Unlike short circuit transfer this metal transfer is a continuous arc process. What this means is once the arc is started the wire never contacts the base metal. Metal transfer occurs across the arc in a cone shaped stream of tiny molten droplets. Im attaching a picture of a sketch that should give you an idea of what the arc looks like.

        Current density on this mode of metal transfer is high , which amounts to a deep penetrating weld. Material thickness is usually 1/4" and above, but can be used on material as thin as 1/8". The weld puddle is quite fluid so the processes has position limitations. Butt joints can only be welded in the flat position, and fillets can be welded in the flat and horizontal position.

        The smallest machine in the Hobart/Miller line that can produce the mode of transfer is the MM 251.

        Im also posting a picture of what a weld bead looks like.
        Last edited by Dan; 05-01-2009, 08:16 AM.
        MigMaster 250- Smooth arc with a good touch of softness to it. Good weld puddle wetout. Light spatter producer.
        Ironman 230 - Soft arc with a touch of agressiveness to it. Very good weld puddle wet out. Light spatter producer.


        PM 180C



        HH 125 EZ - impressive little fluxcore only unit

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        • #5
          The example picture that I m posting here was produced using spray transfer parameters, but the sheilding gas used was 75% argon/ 25% CO2. So you will see some spatter that would not exist if the proper shielding gas was used. The arc started out as a globular transfer than changed to a spray about a 1/4 of the way down the joint. To make this occur though I had to run a much higher voltage than I would with a shielding gas containing the proper Argon level. Anyway minus the spatter the weld bead looks similar
          Last edited by Dan; 05-01-2009, 08:16 AM.
          MigMaster 250- Smooth arc with a good touch of softness to it. Good weld puddle wetout. Light spatter producer.
          Ironman 230 - Soft arc with a touch of agressiveness to it. Very good weld puddle wet out. Light spatter producer.


          PM 180C



          HH 125 EZ - impressive little fluxcore only unit

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          • #6
            ok, i understand the process a little better now that i have seen some pictures. definately not a process for the hobbyist. thanks for the information.

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            • #7
              The pros only use spray arc on steel thicker than 1/4" using solid wire > .045 and state it needs >250 amp MIG welder. The welder only needs to meet all of the welding parameters for spray arc steel welding.

              Here they are from esabna. Used 98/2 Argon/O2 gas.
              .023" wire 100-125 amp 23-25 V 400-620 ipm

              .030" wire 160-200 amp 25-27 V 500-650 ipm

              .035" wire 180-230 amp 25-27 V 400-550 ipm

              .045" wire 260-340 amp 25-30 V 300-500 ipm

              .052" wire 275-400 amp 26-33 V 265-390 ipm

              .062" wire 290-400 amp 26-36 V 180-280 ipm

              So a 175 or 200 class MIG welder could spray arc if they can meet voltage and feed rate requirments using .023 or maybe .030 wire (volt problem). Most can't as they are designed for short circuit welding. This includes HH175. Rock stated on old board the HH175 and Millermatic 175 had highest feed rate of class so he tried it with a Millermatic 175. To him it looked and sounded like spray arc.

              Just nice to know as I don't need another shielding gas. I think this would be more useful if your trying to MIG pulse weld. Then you could probably spray arc all positions and on thinner metal.
              Last edited by Roger; 10-24-2002, 06:09 PM.

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              • #8
                Haybine, this...is...spray transfer

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                • #9
                  Spray arc attempt.

                  Well, I didn't have the right gas, didn't have the right filler wire (dual gas flux core). But gave it a shot anyway. Needless to say appearance wasn't great. Penetration was there. Nice warm big puddle. But lots of flux mixing in the puddle and resulting pores. Slag usually comes off easily. Had to really beat on the piece to get the slag off and off course reveal more pores.

                  Maybe one of these days....
                  Nothing is as easy as it ought to be!

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                  • #10
                    Dual shield uses electrode + like solid MIG wire.

                    Here are some links for Hobart Dual Shield wires with welding data to get you close to right settings.
                    I got them by following welding links at top and bottom of pages on this board.
                    There is lots more wire data at those links. Other manufactures also have this kind of data available.
                    http://www.hobartbrothers.com/pdf/Excel_Arc71.pdf
                    http://www.hobartbrothers.com/pdf/FormulaXL_525.pdf
                    http://www.hobartbrothers.com/pdf/FormulaXL_550.pdf

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                    • #11
                      I got to try spray arc in welding classes last month, but this post has more information about the how and why than I got from my instructor. Come to think about it, I learned more about welding in my first day on this board than a whole month in classes! (except for the actual hands on experience)

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                      • #12
                        In my last post the Arc71.pdf link said, "It can be used with either 100% CO2 or 75% Ar/25% CO2 shielding gas, offering a spray type transfer of weld metal." As I understand it even when welding with fluxcore or metal core wire looks like and sounds like spray transfer including high speed photography of metal transfer it isn't called spray transfer. Spray transfer term is only properly used when welding with solid wire and Argon rich shielding gas at least 75%.
                        Metal core wire (powdered metal core wire) can also produce "spray type transfer".


                        I posted some spray transfer welding parameters from Esab here is link for HB28 wire data with welding parameters.
                        http://www.hobartbrothers.com/pdf/HB28.pdf

                        Note that Hobart doesn't show spray transfer welding parameters for .024 and .030 wires but this Esab link does. How ever these Esab welding parameters are not as useful as Hobart's which list settings for thickness of work and wire thickness.
                        http://www.esabna.com/ESAB/showdetl....=1323&CATID=22

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