Aram wants to use a low duty cycle mig welder. I had one and sold it years ago. It was very frustrating welding thin 14 gauge steel pipe and having the welder overheat every 15 minutes or less.
Many industrial mig welders have 100% duty cycles, so you can weld continuously without overheat issues. Most of the mig welders used on production lines have 100% duty cycles. But they cost a LOT more than the Harbor Freight units. If you have 3 phase power available you can buy decent 100% duty cycle mig welders for not much on Ebay. Oftentimes the feeders need repairs but the power sections are extremely robust. Hobart made some 3 phase mig welders that are very hard to kill. Dave On 7/29/2014 5:22 PM, dave wrote: > On Tue, 2014-07-29 at 22:51 +0200, Lars Andersson wrote: >> Yes, >> at full current this machine has 20% intermittence factor, at 75A or >> less this machine can weld continiously. 75A is fine for what I do. >> For TIG I think you do not need long continious weld times. Might be >> different if you CNC it though. >> >> I am not a professional welder and I work mostly in stainless or mild >> steel, so I have to take it easy and let the work piece cool down. >> Stainless moves around a lot with heat. Weld a centimetre in one place, >> move to another part of the joint and weld some there etc. >> >> The CNC thing I tried was to automate pipe welding by putting the pipes >> on a rotating axis and then rigidly place the torch over the joint to be. >> The result was not very exciting so I put this project aside. (Like most >> of my projects) >> >> >> >>> Hi >>> someone say that all welders - can work - continuously only 1-2-3 minute >>> and than need about 10 minute to cool down. >>> is this right? >>> also when deposit part with welding - should it have cool down time ? >>> because it will get super hot and it may result in warping -deformation? >>> did you find those problem? >>> >>> >>> >>> >>> On Tue, Jul 29, 2014 at 12:16 PM, Lars Andersson <[email protected]> >>> wrote: >>> >>>> In this case I did blindly control the weld current via the PWM output. >>>> The TIG machine is a current regulating controller, it keeps the current >>>> to what is commanded. >>>> The unit I controlled was an Kemppi Mastertig 1500 >>>> >>>> I did initially measure the current with a clamp on toroidal DC probe on >>>> the return lead. You might think that the arc-start spark voltage is a >>>> problem, but it worked quite well for me. >>>>> Hi >>>>> Lars >>>>> ---I am doing something similar with a TIG welder where 0 - 5V >>>> corresponds >>>>> ---to 0 - 160A welding current. >>>>> >>>>> >>>>> what kind sensor-device do you use to read 160A current ? >>>>> >>>>> thanks >>>>> aram >>>>> > Me thinks there are water cooled TIG torches for a reason. On the > missile sites ( Atlas and Titan I) they used Hobart 300 amp welders. > Unfortunately we never got to see them weld as we arrived at the end of > their shift to do X-ray. The pipe was schedule 40 thru XX in diameters > between an inch and 1.75 inches. But that was > 50 years ago so who > knows if I remember correctly. > > For heavy use there are two issues here. The duty factor of the welder > and the duty factor of the torch. > > As an aside I keep wondering how you are going to feed filler rod? > > Dave >>>> >>>> ------------------------------------------------------------------------------ >>>> Infragistics Professional >>>> Build stunning WinForms apps today! >>>> Reboot your WinForms applications with our WinForms controls. >>>> Build a bridge from your legacy apps to the future. >>>> >>>> http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk >>>> _______________________________________________ >>>> Emc-users mailing list >>>> [email protected] >>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>> >>> ------------------------------------------------------------------------------ >>> Infragistics Professional >>> Build stunning WinForms apps today! >>> Reboot your WinForms applications with our WinForms controls. >>> Build a bridge from your legacy apps to the future. >>> http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk >>> _______________________________________________ >>> Emc-users mailing list >>> [email protected] >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >> >> ------------------------------------------------------------------------------ >> Infragistics Professional >> Build stunning WinForms apps today! >> Reboot your WinForms applications with our WinForms controls. >> Build a bridge from your legacy apps to the future. >> http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk >> _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > ------------------------------------------------------------------------------ > Infragistics Professional > Build stunning WinForms apps today! > Reboot your WinForms applications with our WinForms controls. > Build a bridge from your legacy apps to the future. > http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Infragistics Professional Build stunning WinForms apps today! Reboot your WinForms applications with our WinForms controls. Build a bridge from your legacy apps to the future. http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
