help...miller's stt (rmd) on stainless

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tonight I'm just messing around with miller's version of stt process... rmd... on stainless but it's not going so wellI'm using the pipeworx 350 with smart feeder.035 wire1/8 - 5/32 gaptapered nozzlestainless pipe all cleaned (heavy wall)no back purge on the inside100% argon gas (wrong gas I know)the smart feeder don't have a setting for 100% argon .. so this might be my problemI've set the machine to 1.7 for volts/arc length and 149 on wire speedit's give me a mig like weld, with the short circuit process and not a clean spray kind of like a proper sttthe root isn't heavy and might be OK except that it's totally sugared.... I'm using 100% argon and not the argon/co2 or helium trip mixturedoes anyone have any suggestions on the machine settings? or technique suggestions for in postion welding on pipe? not rollingty in advance
Reply:Well you have your answer right in front of you. Wrong gas and no purge. You need a reactive gas mixed with your argon to get into spray. Try adding 2℅ co2, commonly called stain-mix. Any more than 5% and you can get intergranuler corrosion. Or you can go with tri mix, but that is costly.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:we figured it might have been the gas and got a bottle of tri mixty for your post, greatly appreciatedLast edited by then3wguy; 09-17-2014 at 01:46 PM.
Reply:Im thinking you may have STT confused, STT is meant to be a short circuit process, not a spray process.Sent from my LG-P716 using Tapatalk
Reply:The job im currently on we weld 304 with 316 wire, using lincoln STT 2's, argon helium gas with no purge, on open root pipe, no need for purgeSent from my LG-P716 using Tapatalk
Reply:we got the machine dumped off for us to try with the tri mix gas but the roots are totally sugared and heavy roots...not sure which settings to try for... only got a 'arc length' setting from -3 to 3 and a wirespeed setting. .. been trying 1.7 and 149 ws. ... no such luck
Reply:Originally Posted by then3wguytonight I'm just messing around with miller's version of stt process... rmd... on stainless but it's not going so wellI'm using the pipeworx 350 with smart feeder.035 wire1/8 - 5/32 gaptapered nozzlestainless pipe all cleaned (heavy wall)no back purge on the inside100% argon gas (wrong gas I know)the smart feeder don't have a setting for 100% argon .. so this might be my problemI've set the machine to 1.7 for volts/arc length and 149 on wire speedit's give me a mig like weld, with the short circuit process and not a clean spray kind of like a proper sttthe root isn't heavy and might be OK except that it's totally sugared.... I'm using 100% argon and not the argon/co2 or helium trip mixturedoes anyone have any suggestions on the machine settings? or technique suggestions for in postion welding on pipe? not rollingty in advance
Reply:thanks... I might try another joint tomorrow  with the tri mix going to the gunand I might put a Y on the tri mix to purge the pipe with that also or try a 100% argon purge or maybe both at separate times to see what happensthe rooting with no back purge so far has been awful.. total I'll try your settings too for the machine and see what happensthanks again for taking the time to postany suggestion on gap size?Last edited by then3wguy; 09-18-2014 at 04:16 AM.
Reply:Simply putting a y fitting on your bottle to purge will not  work . As you will not be able to confirm the proper flow to your torch. A tee for another flow gauge will.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by then3wguythanks... I might try another joint tomorrow  with the tri mix going to the gunand I might put a Y on the tri mix to purge the pipe with that also or try a 100% argon purge or maybe both at separate times to see what happensthe rooting with no back purge so far has been awful.. total I'll try your settings too for the machine and see what happensthanks again for taking the time to postany suggestion on gap size?