Announcement

Collapse
No announcement yet.

MIG welding aluminum - black residue

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • MIG welding aluminum - black residue

    I am back with more aluminum welding questions, but this time MIG welding aluminum. When MIG welding 1/8” aluminum I am getting a lot of black residue (carbon?). The weld bead looks nice and shiny and is surround by line of oxide, but around that is about 1/4" of black residue. The residue is easily wiped off with a paper towel.

    Being new to welding, this may be entirely normal, however, when we first got the machine (MM252 w/ spoolmatic 30A) we tried MIGing some aluminum using our TIG argon and there was not nearly as much residue. We originally used the recommended setting of 19V which seemed to be enough for spray transfer to occur. Now, we needed to increase the voltage to 20.5V for spray transfer to occur. The only difference that I can think of is that we just received new argon.

    My first thought was contaminated Argon, but we attached the spoolgun to the tank we use for TIGing and we got the same results. I used that same tank to do a couple of beads with the Dynasty and things seemed fine (shiny bead, good cleaning, no mysterious residue). So, I am starting to doubt that it is the Argon.

    Also, the metal has been cleaned with a stainless steal brush and wiped down with acetone. We have tried argon flow rates of 25-35 cfm.

    Thanks
    Dynasty 200DX
    MM252 w/ Spoolmatic 30A
    Spectrum 675

  • #2
    i assume you are running 5356 alloy?

    if the soot really bothers you try some 4043. it is very common with 5356 and it dosen't hurt anything, it's just a PITA to wipe it off all the time
    The one that dies with the most tools wins

    If it's worth having, it's worth working for

    Comment


    • #3
      Originally posted by tigman250 View Post
      i assume you are running 5356 alloy?

      if the soot really bothers you try some 4043. it is very common with 5356 and it dosen't hurt anything, it's just a PITA to wipe it off all the time
      I forgot to mention that we are using 4043.
      Dynasty 200DX
      MM252 w/ Spoolmatic 30A
      Spectrum 675

      Comment


      • #4
        No sweat. Happens to me all the time. A rag gets rid of it!

        Hank
        ...from the Gadget Garage
        Millermatic 210 w/3035, BWE
        Handler 210 w/DP3035
        TA185TSW
        Victor O/A "J" series, SuperRange

        Comment


        • #5
          Originally posted by grumpy42 View Post
          When MIG welding 1/8” aluminum I am getting a lot of black residue (carbon?).
          ROFLMAO. Welcome to the club. Good answers so far. Just wait until you are doing some GTAW and you dip your tunsten into the puddle or shove your filler rod onto the hot tungsten while you are welding.
          Dynasty 350DX
          Dynasty 200DX TigRunner
          MM 350P
          MM Passport Plus
          Spectrum 375 Extreme
          08' Trailblazer 302

          Comment


          • #6
            Thanks for the replies. Being new to this I really don't know what to expect.

            I was just concerned since we seemed to be getting a slightly different result from the first time we tried the machine and the only change was the new argon. Perhaps it was just the alighnment of the stars.

            So since there is nothing to worry about, we can move on to ruining more metal - and we can't even blame it on the equipment
            Dynasty 200DX
            MM252 w/ Spoolmatic 30A
            Spectrum 675

            Comment


            • #7
              Grumpy,

              Don't feel picked on. Sometimes, we (us old farts) forget to notice the number of posts that an OP has.

              Believe me when I tell you that when I joined this forum, I was greener than healthy grass. I got where I am now (some may wonder if that's a good thing! ) through a lot of ruined steel and aluminum, a healthy respect for advice from knowledgeable folks, who proliferate these forums, and membership (and participation) in these on-line wonderful knowledge repositories!

              We all gotta start! Hang in, and keep the questions coming.

              Hank
              ...from the Gadget Garage
              Millermatic 210 w/3035, BWE
              Handler 210 w/DP3035
              TA185TSW
              Victor O/A "J" series, SuperRange

              Comment


              • #8
                Originally posted by grumpy42 View Post
                Thanks for the replies. Being new to this I really don't know what to expect.

                I was just concerned since we seemed to be getting a slightly different result from the first time we tried the machine and the only change was the new argon. Perhaps it was just the alighnment of the stars.

                So since there is nothing to worry about, we can move on to ruining more metal - and we can't even blame it on the equipment
                one more thing, try pushing the puddle, pulling always produces alot of soot pushing reduces it greatly.
                The one that dies with the most tools wins

                If it's worth having, it's worth working for

                Comment


                • #9
                  the black residue is standard opperation, pushing however creates less black soot
                  mm210
                  maxstar 150

                  Comment


                  • #10
                    Weld Smut...Bob http://www.thefabricator.com/Aluminu...cle.cfm?ID=554
                    Bob Wright

                    Spool Gun conversion. How To Do It. Below.
                    http://www.millerwelds.com/resources...php?albumid=48

                    Comment


                    • #11
                      Originally posted by aametalmaster
                      Great link. Thanks.

                      Good to know that it is normal. After doing some experimentation I finally realized that the amount of smut deposited is dependant on the angle of the gun. I was pushing the puddle but I also wasn't holding the gun vertical to the direction of travel so I was creating rather large streaks of smut.

                      All of the descriptions of spray transfer of aluminum that I had read, had described the process as "clean", so, due to my lack of experience, I was a little surprised by the mysterious black residue. I also could not think of where it would come from - it was certainly surprising to find out that the black smut is actually aluminum oxide.
                      Dynasty 200DX
                      MM252 w/ Spoolmatic 30A
                      Spectrum 675

                      Comment


                      • #12
                        Even i learned from the article. I just welded 4 alum columns that were formed from 16 ga sheet alum to a cast base that was only like .100 thou thick. I lowered my stickout putting the nozzle closer and straighten up my gun position a little and the welds came out shiney. Guess i was also getting "suckback" as described in the article on my earlier welds and i have been doing alum spoolgun welding for 30+ years...Bob
                        Bob Wright

                        Spool Gun conversion. How To Do It. Below.
                        http://www.millerwelds.com/resources...php?albumid=48

                        Comment


                        • #13
                          Originally posted by tigman250 View Post
                          one more thing, try pushing the puddle, pulling always produces alot of soot pushing reduces it greatly.
                          Exactly!
                          I also found using a bigger gas nozzle produces less soot with my cobramatic(not sure you can use bigger gas nozzles with your setup?). And, block all wind/breeze or it blows your shielding away.
                          Millermatic 180 DC,Miller Spoolmatic 3,Miller HF-251-D1 __ Lincoln Cobramatic/Cobramatic Gold
                          Millermatic 200 with pulse/spot/burnback panel DC ______Lincoln Idealarc Tig 300/300 AC/DC
                          Miller ECONO twin HF 150 AC/DC .____________________ Lincoln Idealarc R3R 300 DC
                          Miller Trailblazer 250G AC/DC (20hp. Onan) .____________ Lincoln Buzz box 225/125 AC/DC
                          O/A Harris, Purox, Victor, Torchweld (To many to list) .___AIRCO wire feeder

                          Comment

                          Working...
                          X