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Overhead Flux core 3/8 V groove test

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  • Overhead Flux core 3/8 V groove test

    I am going to take the flux core test friday and wanted to know if anyone has any advice on the overhead weld. I am having trouble with that weld any advice would be great. Also it is 045 wire with sheild gas

  • #2
    Hey J-W-M,
    You pose a dilemma for we members to provide advice/solutions since you fail to illuminate us as to the problems you are having. Since you indicate .045 wire & shielding gas, we will presume you will be using "dual shield" wire, not straight flux-core. Also, overhead on what size/configuration/thickness, etc...... fill in some blanks for us.....



    • #3
      Run it just like you would in the flat position, same settings, same slight drag angle on the gun. You'll have to stop and clean out your gas nozzle more often but otherwise it's just like a flat 3/8 v-groove. Throw the whip over your shoulder so your arm doesn't get tired so quick and stand off to the side so you don't get rained on with spatter as much.


      • #4
        I am having trouble getting the puddle to stay up on my first pass. The second pass I can handle fine. Also do you need to change the polarity on a 251 miller mig welder with duel sheild when you change the wire to flux wire.


        • #5
          Fluxcore self shield runs DCEN. Generally, fluxcore gas shield and solid wire with gas both run DCEP.

          Not sure what you mean by trouble getting the puddle to stay up. Is it dripping out? Maybe you have it too hot, or have the inductance set to too wet...


          • #6
            Originally posted by Desertrider33 View Post
            Not sure what you mean by trouble getting the puddle to stay up. Is it dripping out? Maybe you have it too hot, or have the inductance set to too wet...
            Or possibly wrong gun angle. Sometimes when people start running overhead they get somewhat disoriented. Takes a little time to learn the proper gun angle so the puddle doesn't end up on their shoes.


            • #7
              Originally posted by Desertrider33 View Post
              Maybe you have it too hot, or have the inductance set to too wet...
              I don't believe the Millermatic 251 has a dial to adjust the inductance.


              • #8
                I haven't run an overhead fluxcore v groove. I'm just wondering if you would benefit from running a little higher wire speed on overhead as compared to flat?


                • #9
                  Originally posted by jrscgsr View Post
                  I'm just wondering if you would benefit from running a little higher wire speed on overhead as compared to flat?
                  That will dry the puddle out to a degree.

                  Personally I think Desertrider33's advice is dead on! Sometimes on an overhead fillet weld I'll run hotter / faster than a flat V-groove.

                  I think most newbies to overhead get a mental block, a fear of being burned. Well guess what you're going to get burned sooner or later, might as well get use to it!


                  • #10
                    overhead spatter


                    I'm a bit new to fluxcore but must say I love it... and I've been a welder since 1994 so I took right to it.

                    I'm also looking to take a 3/8" metal weld test (30 degree bevels) in overhead flux core.

                    I ran my vert & horiz. with no problems but when I went to do over head I was rained on by massive spatter... like more metal on the floor than on the metal.

                    eventually I got it to "purr" again and began to make very nice overhead welds. I switched out my practice metal for a test coupon and though it seemed like I changed nothing, the rain came back. Like everything was fine on my practice plate but as soon as I switched out for a test coupon, I couldn't get the metal to stick to my test plate.

                    Can anyone help with why that is? Is there a difference being "in the groove" for this symptom, than just running on the surface of a practice plate?



                    • #11
                      me again

                      I was running 75/25 gas, and was using 2 machines to weld with. One was a "roller machine" that the gun and spool was connected to and the other was just a welding machine that connected to... and powered the "roller machine."

                      I had the welding machine heat set to 130 and the wire speed set to 230. That setting ran like a dream in vert & horiz. The slag was falling off with a flick of my finger.


                      • #12
                        if your having trouble getting the first pass to stick and it's drippin out then your running to hot and to slow. i always used the pointed tip nozzles for overhead because they was alot less likelkly to act like a cup and catch all the slag .we also always used flex guns they are nice you can bend them to whatever angle you needed. do like the others said and through the whip over your shoulder and run the gun upside down .i always held my gun nozzle stright up with no angle for overhead welds. also how big of a space do you have in between plates? i found on plate welds it's best to but them up with no gap then after welding the overhead i would go up top and gouge a groove out or just cut a groove with the grinder and run a single pass on it if it was 1/2" thickness or less anything thicker and they always wanted a 2 or 3 pass cap on it.


                        • #13
                          me again one more time

                          .045 wire


                          • #14
                            Thanx for getting back to me.

                            I was using a 1/4" gap. It's for a welding test so I'm not sure if they'll let me adjust it to tight... but thanx for that advice... I'll get it as tight as they let me.

                            I did go right to fiddling with the controls when I started having problems. and it worked eventually. The main thing that concerns me is that it was running perfect on my practice plate and then put me to struggling on my test plate... without any changes. That's really got me confused as to why that is. I'm hoping that if I can understand why that happened... that I might be able to avoid it when I take the real test.


                            • #15
                              This may be of little to no help, and I apologize, but yeah, a lot of it is just messing with the settings till you dial it in. The machines we have at work are pretty finicky (and I don't flux-core that often). A lot of guys get into a hurry, like to just get it close, then start welding. they put up a decent weld, but they have a pile of little BB's to grind below the weld. If you get the wire speed set just right, you should have little to no spatter to worry about. I've found that if the puddle is falling out, you may actually have too much wire speed, especially if running hot, like I like to do. If you are steady enough to weld with one hand, start running a bead and adjust your wire speed until you get a nice hissing sound as you weld, there shouldn't be any crackling noise if it's set just right. (I've found welding is as much about sound as it is about seeing)
                              For filling in the groove, you really gotta watch your puddle, especially in O.H. As soon as both sides of the groove are fused, move forward, too long in one spot and metal will rain. I like to pull a bit and pause, or even push back just a hair, then jump forward, and repeat
                              Last edited by hockeyguynick; 10-27-2011, 06:41 PM.


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