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Help needed on technique for Fabshield XLR-8 wire

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  • Help needed on technique for Fabshield XLR-8 wire

    I am a welder in Hawaii and am working on a structural steel project welding 3/8” thick square tubing for a building frame. The welds are subject to inspection by a welding inspector. I have been using Excel Arc 71 .045” with good results (passed my first inspection) but there has been a problem coming up with high winds at the site and making the wind shields became impractical. I got a roll of Fabshield XLR-8 in the 1/16” diameter size to use in the wind but am having lots of problems with it, especially welding vertical up. The biggest problem is that the flux does not follow the arc well enough to hold the weld metal when in the vertical up position. Even when running practice beads in the flat position the flux is inconsistent in following the arc and sometimes beads up or splits down the middle. I can get the flux to follow better by reducing the voltage in increments but when it starts looking right the voltage seems too low with a ropey weld and the electrode stubbing into the work at the beginning of the weld.

    I am using a Miller XMT 350 CC/CV (on the MIG or CV setting) with a 60 series wire feeder. The polarity is set to DCEN, inductance +10, voltage at the machine 18V, wire speed 145 IPM, and the machine reads 180 amp while welding. We put a volt meter on the machine while welding and got about 17.5 volts (we tried actually checking at the work piece and got a little less, more like 17). We checked the wire speed by timing and measuring the wire and the 145 imp is accurate. I am using a stick out of 1”. I checked all the connections which seemed ok (the same machine was working fine with the Excel Arc 71 wire in the DCEP polarity setting) and the work piece and ground connection are clean. The wire seems fresh (we just bought it) and we are bagging it in plastic each night to protect from moisture.

    I tried the recommended setting of 21V and 187 ipm also. This was much harder to control in vertical up with the flux beading up and not forming a good shelf at all (it either just beads up randomly or splits down the middle) If I slow down the travel speed to let the flux catch up the electrode sometimes burns right through the work piece.

    I assume that with practice I could do better but it seems like something else might be wrong and I need to solve this quickly to proceed with the job.

    Please advise if there is something I am missing. Also, any further information on technique with this wire (or if there is a better wire for my application) would be appreciated.

    • What is the recommended gun angle for vertical up? I tried dragging, straight on and pushing. A slight push seemed the best but nothing has worked well yet.
    • What should I look for or adjust to get the flux to come out evenly over the bead and not split or bead up?
    • Should the procedure with this wire be similar to other T-8 wires like NR-232 or are there special things about this wire I should know which make it different.

    Thanks
    Chris Crawford, Space Options, Molokai Hawaii

  • #2
    I have never used this specific wire, but I do have many hours with other T-8 wires (232, Coreshield 8, 233).

    From your description of the slag, sounds like too high voltage. You can probably check the Hobart Brothers website (different from this one) and find a PDF file describing this wire and the proper parameters.

    Are you maintaining the stickout you say you are? Any CV machine will produce more voltage with more stickout, I normally keep it tighter rather than looser.

    A correct bead will have a thick, even coat of slag over it, easy to chip off.

    When running vertical up, I normally maintain a straight-in gun angle, or a very slight drag up. Little or no weaving, if you need a bigger bead, run multiple passes. The maximum movement I do, I would describe as I keep the tip in the same location, but move the gun back and forth, basically just changing slightly the direction of the arc.

    Lincoln used to have a good description and explanation of techniques on it's website, probably still does.

    Another thing, very important,,,, many T-8 wires will not weld properly thru a mig gun, you need to use a real innershield/fluxcore gun and liner. They feed thru just fine when not welding, but as soon as you strike an arc, it either stops or slows down. Drive rolls start slipping and spinning, amps go down, volts go up, regardless of what the power source is set at. I think the mig liner is just too flexible for the hard, stiff wire.
    *** Disclaimer ***

    As I have no wish to toy with anybody's life, I suggest you take this and all other posts with a certain amount of skepticism. Carefully evaluate, and if necessary, research on your own any suggestions or advice you might pick up here, especially those from my posts, as I obviously haven't the skill and experience exhibited by some of the more illustrious and more successful members of this forum. I'm not responsible for anything I say, as I drank toxic water when young.

    Comment


    • #3
      Originally posted by calweld View Post
      I have never used this specific wire, but I do have many hours with other T-8 wires (232, Coreshield 8, 233).

      From your description of the slag, sounds like too high voltage. You can probably check the Hobart Brothers website (different from this one) and find a PDF file describing this wire and the proper parameters.

      Are you maintaining the stickout you say you are? Any CV machine will produce more voltage with more stickout, I normally keep it tighter rather than looser.

      A correct bead will have a thick, even coat of slag over it, easy to chip off.

      When running vertical up, I normally maintain a straight-in gun angle, or a very slight drag up. Little or no weaving, if you need a bigger bead, run multiple passes. The maximum movement I do, I would describe as I keep the tip in the same location, but move the gun back and forth, basically just changing slightly the direction of the arc.

      Lincoln used to have a good description and explanation of techniques on it's website, probably still does.

      Another thing, very important,,,, many T-8 wires will not weld properly thru a mig gun, you need to use a real innershield/fluxcore gun and liner. They feed thru just fine when not welding, but as soon as you strike an arc, it either stops or slows down. Drive rolls start slipping and spinning, amps go down, volts go up, regardless of what the power source is set at. I think the mig liner is just too flexible for the hard, stiff wire.
      Thanks a lot for taking the time to help out. I did check the Hobart site and got the right voltage. I think you are right that when the flux was beading up instead of covering the bead properly, the voltage was too high for the wire speed. We did get a special flux core gun for this from miller which is working ok. Maintaining the stick out is a challange and does seem to really affect the behavior of the flux. I was having lots of trouble trying to do stringers in vertical up so I called Hobart and talked to Ivan there who recommended some stitching instead of straight stringers since for the thickness I am working with (3/8" with 1/4" backer bar) the arc sometimes burns too deep if you don't really keep it moving but at the same time you need to go slow enough to let the flux shelf build, so going sideways a bit seemed to help. I looked at the Lincoln website which has some great instructions but Hobart said this wire is significantly different than NR-232. It is supposed to be closer to NR-233 but did not see any instructions on the Lincoln website for 233. Ivan at Hobart said they have an instruction video for the Fabshield XLR-8 which he is sending. Thanks again for your help.
      Chris Crawford, Space Options, Molokai Hawaii

      Comment


      • #4
        I completely forgot about this earlier, you should go over and do a search on the AWS website. A couple of years ago, there was somebody who gave absolutely the best tutorial on T-8 wire I've ever seen, worth printing out. I'd post a link, but I didn't save it. Mostly concerning NR-232, but techniques on T-8 wires are almost always similar, just the parameters change. Note that NR 233 and ESAB T-8 wires are much less finicky than 232; your Hobart wire probably is so also, but if you can run 232 you can run the others.
        *** Disclaimer ***

        As I have no wish to toy with anybody's life, I suggest you take this and all other posts with a certain amount of skepticism. Carefully evaluate, and if necessary, research on your own any suggestions or advice you might pick up here, especially those from my posts, as I obviously haven't the skill and experience exhibited by some of the more illustrious and more successful members of this forum. I'm not responsible for anything I say, as I drank toxic water when young.

        Comment


        • #5
          thank you for post....
          herbalife

          Comment

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