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  • Porous plug welds

    Looking for sone help, fairly new to welding. . Here’s the situation:

    1) welds are porous, same type of weld regardless of the setting

    2) machine has welded fine in the past. Have not used for 6 months.

    3) brand new tank of gas, brand new .024 wire Same result with .030 wire

    4) I do not hear or feel any gas at the nozzle. Holes for gas are clear, I did check.

    5) machine welded fine when it was last used.

    7) welder is about 2.5 years old

    8) settings were correct per the chart.

    9) tried gas’s settings from 16 through 21 psi, same result

    any help in figuring this out would be very appreciated. Thanks!

  • #2
    Originally posted by Bill M View Post
    Looking for sone help, fairly new to welding. . Here’s the situation:

    1) welds are porous, same type of weld regardless of the setting

    2) machine has welded fine in the past. Have not used for 6 months.

    3) brand new tank of gas, brand new .024 wire Same result with .030 wire

    4) I do not hear or feel any gas at the nozzle. Holes for gas are clear, I did check.

    5) machine welded fine when it was last used.

    7) welder is about 2.5 years old

    8) settings were correct per the chart.

    9) tried gas’s settings from 16 through 21 psi, same result

    any help in figuring this out would be very appreciated. Thanks!
    Do you hear the gas valve opening when you pull the trigger?

    Comment


    • #3
      Increase your pressure to at least 30 or higher. If you cannot hear gas discharge out the business end of the nozzle you may have to disassemble it for a good cleaning.

      Comment


      • #4
        The greatest barrier to making a good plug weld, is the angle of the gun, or electrode. You have to make a swirly.

        Click image for larger version

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        This is an average plug weld.

        Click image for larger version

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        You will have problems if you don't aim the electrode at the outer walls of the hole. You can't plunge it into the center, and expect it to do a good job. You'll get porosity. You have to run the weld around the outside diameter of the hole, and let the middle fill in. It's not important if the middle fills in...…..what's important is fusing the outside diameter of the hole with the base metal.

        Go around the outside, watching yer puddle, and connect at the end of the circle. Ignore what's happening in the middle. A plug weld derives its strength at the outside, not in the middle. Fill the middle when you become proficient at it.

        Click image for larger version

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        Comment


        • #5
          What welder do you have?

          It does look like a gas problem.
          Last edited by coxhaus; 03-24-2020, 03:10 AM.
          Hobart beta-mig 2510 Mig welder
          Victor OA Welding/Cutting Rig
          Century 295 amp Stick welder bought 30+ years ago

          Comment


          • #6
            Thanks for the advice! I did turn it up to 30 psi and still did not hear any gas. Will check out the manual and look up the process to clean the line for starters.

            Comment


            • #7
              IS it PSI or CFH ... Most MIG regulators are rates in CFH ( I know its actually just a differently calibrated pressure gauge and orifice to convert to CFH) .....

              Check gas system... Is tank on (I now sort of stupid question) is gas getting to inlet of welder, is gas solenoid operating (it been know to have loose connection at solenoid so it doesn't operate)...There has even been cases where hose has come off out put of control valve and your shield gas just vent to atmosphere instead of being directed to gun tip.... Remove the contact tip and it's holder and see if you have gas at end of gun wand.....




              Make sure "D" in image above. is clean...

              Dale
              Last edited by Dale M.; 03-24-2020, 12:27 PM.
              "Fear The Government That Wants To Take Your Guns" - Thomas Jefferson..

              Comment


              • #8
                Originally posted by Northweldor View Post

                Do you hear the gas valve opening when you pull the trigger?
                Why not answer this?

                Comment


                • #9
                  Here is a response from an AWS expert concerning ideal gas pressure settings.
                  " By Lawrence (*****) Date 05-03-2017 21:57 Edited 05-03-2017 22:06
                  A "hobbyist" is not gong to take into consideration conditions such as joint type, type of gas, size of filler, amperage or travel speed. So 35 CFH covers most all bases.

                  A hobbyist is not going to be spending great amounts of arc time, so being economical with shield gas is not a pressing issue. So again, they are not going to be making calculations that result in gas flow economy... 35 is a fine rule of thumb. You are an expert North, and think of these conditions and can wisely conserve due to your ability to judge what is necessary, and a hobbyist will never do that.

                  A "beginning welder" is going to have many changes in both gun angle and CTWD (stick-out) so being stingy on shield gas flow is just opening the door for trouble... 35 CFH would be my minimum recommendation for a beginning welder.

                  I have seen very few production GMAW WPS's for short circuit or spray transfer GMAW that called out less than 35 CFH... So if I were working with 15 welders *beginners* I would again run at least 35 CFH gas flow and then evaluate the welds. Excessive silicon deposits, grey puckering, smoky weld toes are all signs of insufficient gas flow that I would be looking for on the shop floor with these 15 welders.

                  If I'm responsible for a weld shop (and I am, for several) I don't want my WPS's to be running on the ragged edge of porosity and failure due to poor gas coverage, caused by a technique issue combined with economizing on shield gas... I want a robust procedure that will work for variations within WPS limits on gun angle, travel speed, fit-up, fans, exhaust, sneezes and coughs and anything else that can spoil a weld.

                  The cost of a single backcharge for back-gouge and reweld in the field or an ******** site is typically more than the monthly savings of reducing shield gas in 15 workstations by 10 CFH.

                  Sorry to be oppositional... But I just don't see any value in this type of economizing outside of my own garage where *I'm* the expert and have complete control "

                  Comment


                  • #10
                    Originally posted by Hunter55 View Post
                    Here is a response from an AWS expert concerning ideal gas pressure settings.
                    " By Lawrence (*****) Date 05-03-2017 21:57 Edited 05-03-2017 22:06
                    A "hobbyist" is not gong to take into consideration conditions such as joint type, type of gas, size of filler, amperage or travel speed. So 35 CFH covers most all bases.

                    A hobbyist is not going to be spending great amounts of arc time, so being economical with shield gas is not a pressing issue. So again, they are not going to be making calculations that result in gas flow economy... 35 is a fine rule of thumb. You are an expert North, and think of these conditions and can wisely conserve due to your ability to judge what is necessary, and a hobbyist will never do that.

                    A "beginning welder" is going to have many changes in both gun angle and CTWD (stick-out) so being stingy on shield gas flow is just opening the door for trouble... 35 CFH would be my minimum recommendation for a beginning welder.

                    I have seen very few production GMAW WPS's for short circuit or spray transfer GMAW that called out less than 35 CFH... So if I were working with 15 welders *beginners* I would again run at least 35 CFH gas flow and then evaluate the welds. Excessive silicon deposits, grey puckering, smoky weld toes are all signs of insufficient gas flow that I would be looking for on the shop floor with these 15 welders.

                    If I'm responsible for a weld shop (and I am, for several) I don't want my WPS's to be running on the ragged edge of porosity and failure due to poor gas coverage, caused by a technique issue combined with economizing on shield gas... I want a robust procedure that will work for variations within WPS limits on gun angle, travel speed, fit-up, fans, exhaust, sneezes and coughs and anything else that can spoil a weld.

                    The cost of a single backcharge for back-gouge and reweld in the field or an ******** site is typically more than the monthly savings of reducing shield gas in 15 workstations by 10 CFH.

                    Sorry to be oppositional... But I just don't see any value in this type of economizing outside of my own garage where *I'm* the expert and have complete control "
                    Really does not help problem of no gas flow troubleshoot....

                    Dale
                    "Fear The Government That Wants To Take Your Guns" - Thomas Jefferson..

                    Comment


                    • #11
                      Originally posted by Northweldor View Post

                      Do you hear the gas valve opening when you pull the trigger?
                      No I could not. Will check through the line and see if it came off or needs to be cleaned. Thank you.

                      Comment


                      • #12
                        Originally posted by Dale M. View Post
                        IS it PSI or CFH ... Most MIG regulators are rates in CFH ( I know its actually just a differently calibrated pressure gauge and orifice to convert to CFH) .....

                        Check gas system... Is tank on (I now sort of stupid question) is gas getting to inlet of welder, is gas solenoid operating (it been know to have loose connection at solenoid so it doesn't operate)...There has even been cases where hose has come off out put of control valve and your shield gas just vent to atmosphere instead of being directed to gun tip.... Remove the contact tip and it's holder and see if you have gas at end of gun wand.....




                        Make sure "D" in image above. is clean...

                        Dale
                        Thanks! Will check through the gas line piece by piece tonight. Appreciate the help

                        Comment


                        • #13
                          Originally posted by Bill M View Post

                          No I could not. Will check through the line and see if it came off or needs to be cleaned. Thank you.
                          Then your problem is likely the valve itself, or the relay that operates it. Try tapping both gently, but they may need replacement.

                          Comment


                          • #14
                            Originally posted by Bill M View Post

                            Thanks! Will check through the gas line piece by piece tonight. Appreciate the help

                            Thanks, looked through each connection and found the Jose was a bit loose from the drive assembly. By turning up the gas I could hear it instantly that was the issue and it’s all good now. Really appreciate the suggestion!

                            Comment


                            • #15
                              Click image for larger version

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                              Originally posted by Bill M View Post


                              Thanks, looked through each connection and found the Jose was a bit loose from the drive assembly. By turning up the gas I could hear it instantly that was the issue and it’s all good now. Really appreciate the suggestion!
                              Thanks for the update.
                              --- RJL ----------------------------------------------

                              Ordinarily I'm insane, but I have lucid moments when I'm merely stupid.
                              -------------------------

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