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Am I crazy for not being bowled over by MIG?

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  • Am I crazy for not being bowled over by MIG?

    We finished stick welding in the class, and have moved to MIG.....

    I got decent at stick, and even found overhead to be, if anything, easier than vertical (at least with 7018), but so far after a few hours of MIG, I am not very happy....

    We have big single-phase Miller SMAW/GMAW machines, manifold gas, etc. Settings are IIRC, 0.035 wire, 22V, 375 IPM, with 1/4" stock. 20 on the gas flow.

    Doing the "e" movement, drag, I either get way too much bead width, or too small and pointy-topped. Trying for about 12 to 18" per minute travel, which seems right for the deposited amount.....but that's not at all precise....

    It seems to be really HOT welding, the steel is red after a pass. Like 6010 on steroids.... even blew a hole in the 1/4" x 2" wide material once laying beads flat.

    Keeping contact tube about 1/8 back and about 3/8 to 1/2 stickout, I still have to clean the nozzle about every 24" of bead.... and I get a goodly ring of crap out, too. Yes we have the goo, I warmed up and dunked , and kept it up every so often over the 3 hours of lab.

    I just gotta feel something ain't right, but dunno what. The instructor is helpful, but maybe his answers are not getting into my thick skull, or I am not asking the right questions

    probably I don't know WHAT to ask, exactly.
    1601 2137 5683 1002 1437

    Keep eye on ball.
    Hashim Khan

    If you look closely at a digital signal, you find out it is really analog......

  • #2
    Yeah, you're crazy.

    Just kidding. I only know a little gas welding, soldering, brazing and mig. I've never used stick, though I have watched it.

    I find I can do nice, clean welds that I can't break apart using mig. The spatter is minimal compared to stick. I doubt that any of my welds will pass a professional inspection, but that's why amateurs weld a lot more than is necessary. I count on the 50% of my weld that's really good to make up for any part that is flakey.

    Dan
    At the end of the project, there is a profound difference between spare parts and left over parts.

    Location: SF East Bay.

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    • #3
      375 ipm is screaming hot...try 16-18 OCV and 160 ipm. MIG was originally designed for clean sheet metal and does an outstanding job in that application but depending on gas mix, which I didn't see mentioned, you are likely hitting spray arc levels. Spray arc is very hot and concentrated; it pours in the wire and could very well blow a hole in 1/4" steel. For most work, it is way too much juice.

      Your instructor has probably mentioned that MIG settings are different from stick or TIG. MIG heat is adjusted by tuning voltage and wire speed; TIG/stick is adjusted on current.

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      • #4
        The best way is to experiment - change one thing at a time and observe and note the differences.
        That way you get to understand the relationship between settings and the results

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        • #5
          After 40 years of stick welding and having burned lots of rods, Mig has been harder to learn than I expected. Even with the Millermatic controls that do some of the thinking for you it has been more difficult to get properly adjusted. Once you find the correct settings it starts to come together. Stick welding newbies often ask what the current setting should be for a given thickness of material. Because each machine is differentit is necessary to find the setting for your machine. When stick welding I have always paid particular attention to starting with a good ground. I should have done that with the Mig but I didn’t and it made things harder. My advice is to start with a good ground and a given thickness of material and play with the controls until you find the sweet spot. I was not bowled over by Mig but I am coming to like it better. Hang in there, It is ultimately worth the effort.
          Byron Boucher
          Burnet, TX

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          • #6
            I've found that only a small buildup inside the nozzle, anything more than a couple dingleberries, will cause problems by disrupting the shielding gas flow.

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            • #7
              Gas mix will have a lot to do with the amount of spatter. Straight Co2 will produce a lot of spatter compared to a mix of Argon Co2. I would think the school would most likely be using Co2 because it will be the least expensive gas.

              I generally push the puddle with mig, will give you a flatter bead.

              I doubt you are getting into spray mode at 22v, spray will sound different quiet hissing sound to the arc, short circuit will be a steady crackle like bacon frying. Generally I have found you need to be above 24V to get into spray mode, which I usually use on anything above 1/4" material thickness.

              1/4" material on my machine, I would run about 315ipm 19.5V with an Argon Co2 mix.
              With straight Co2 315ipm 22.5V

              The biggest problem I had when learning mig, was going too slow. Mig is very fast compared to stick/tig, gas welding etc..

              Ed

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              • #8
                Listen to the sound it makes as it should remind you of frying bacon as you weld.

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                • #9
                  I'm with Hwool.
                  Slow down the feed to about 200-220 and go from there. That's what works best on our machine.

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                  • #10
                    I too have to agree with the others, way too hot.
                    Don't get discouraged though it will start to get more easy for you the more arc time you put in.

                    Even after years of mig I still feel more comfortable with stick though.
                    Everybody says mig is easy, anybody can do it in no time.
                    I say BS.
                    Yeah anybody can start an arc and put down what appears to be a bead more quickly with mig than stick. But to lay down a sound bead, following the contours of the weldment isn't that easy.

                    Mig is a very fast process, you have to keep up with what the machine hands you, not always easy keeping up with what is on your plate and laying down an acceptable bead.

                    Like the others say, don't be afraid to experiment with your machine's settings.
                    Not sure what gas your school is using for shielding gas, but straight CO2 will have a bit more spatter and deeper penetration than the typical 75/25 argon/co2 blend.
                    Home, down in the valley behind the Red Angus
                    Bad Decisions Make Good Stories​

                    Location: British Columbia

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                    • #11
                      I've always found MIG to be the easiest/most forgiving WRT your torch angle, arc length. I've got a Lincoln 225. One problem I've seen is guys get a little fast in travel speed MIGing resulting in a decent looking but unacceptable weld (cold toes).

                      Do you have any pics?
                      I bury my work

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                      • #12
                        Your instructor should have explained more about things like Short Arc, Globular and Spray arc welding. There are far many more variables with GMAW than SMAW and the proper gas is just one of them. GMAW can do much more and much faster depending on the operator.

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                        • #13
                          We had a very thorough explanation, so no problems there.....

                          The settings are specified, and gas is 75/25, although I see quite a bit of spatter, and stuff is definitely flying, but nothing like 6010.

                          It seems to be a problem more-or less limited to the flat beads and "pad of beads" practice.... We started on flat position lap and T, and I found that to be much better controlled.

                          Wire speed is current, yes I know that. Definitely still globular transfer by the sound, clear bacon fry... and in any case spray takes more argon than our mix.

                          Whoever said that about "taking what is handed out" is correct, although I found that a bit more stickout controls current a bit without getting porosity, and improved visibility also.

                          I got decent to good welds first tries on lap, with good fill, and the toes looked good to me, although the instructor complained about convexity and the plate-side toe.... I think he was looking at one where I tried "horizontal" and didn't get a good result.

                          I also did not find the IPM too high on actual welding, I had to go slower to get the fill. I calculated the fill based on IPM, and found that for a 1/4" leg it was only a foot or so per minute of torch travel if you want to fill out the bead to a full flat face.

                          With the running of beads on flat, I was getting too much down, and I had to speed up a bit.... leading to a situation of getting "behind the machine".... but it was not so bad with an actual weld.

                          After doing stick, the actual weld was easier than running beads on the flat, so long as I kept a good view of the pool. Someone suggested marking a line, and that was really good advice.... I marked the end also, and stopped having overshoot "spit-outs" of wire from going past it.
                          1601 2137 5683 1002 1437

                          Keep eye on ball.
                          Hashim Khan

                          If you look closely at a digital signal, you find out it is really analog......

                          Comment


                          • #14
                            Hi All,
                            New to this Forum.
                            I have a Mig and a Stick Welder and like most have gone to useing the Mig for all of my welding, it gives a good weld with good strength but would like to ask thoes with a lot of welding experiance where they would use a Stick Welder over a Mig Welder.
                            Is that with a Stick Welder you can build up good penertrated welds giving maximun strength as you can push the puddle and get deep welds?
                            One of the best Welders i had was a Lincoln DC Welder 3 Phase, but sold it as the place where I am now is only Single Phase.
                            Look forward to your answers.

                            Regards,
                            Keith.

                            Comment


                            • #15
                              Mig has it's purpose and I have burned alot of wire, used to burn 44# of wire a night welding structural steel. As for the settings they don't sound bad, if your running 22v (not sure what Amperage your machine is) and 375 IPM doesn't sound that bad, if anything you need to increase the wirespeed to keep the puddle flowing. If you feel like your waiting for the puddle than the Wire speed needs up'd. It will get to a point where you can feel the wire pushing off the base metal that is when you know it is too much along with excessive splatter and a funny sound. You can get the same results with to little of wore speed but the splatter is alot heavier and you will see alot of undercut where the weld gets to hot.

                              As for pattern or weave, experiment with different patterns and speed. You should be able to control the puddle very well. I welded this with a single phase Hobart Beta Mig 200 amp with .035 wire.

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