Hi all,
Newbie to tig here. First time posting. Pulled the trigger on an Everlast 250EX and the water cooler. I have a lot of respect for you guys out there that can tig weld aluminum. I can't worth a damn. I purchased a new 125 tank off ebay cause the LWS doesn't have that size to sell or lease. Brought it down with anticipation of leaving it there to get it purged and filled at the disposal. The guy says he'll do it while I wait. Now let me preface this with when I got the tank delivered it was empty and the valve was wide open. I told the filler this and he just shrugged and proceeded to pipe it into his manifold of about eight 330's. He put in a short burst of argon, then disconnected and let that go out into the atmosphere. Then he hooked back up my tank and opened the manifold letting the pressure of eight 330 tanks into mine. This took about 15 minutes time. I sat in the truck as it was cold out. Paid the guy his 65 dollars and went home. Hooked up the tank to my new Argon flow meter that came with the unit and it reads 1800lbs. So I kinda figured I didn't really get the full tank being that it was equalized pressure from their tanks that were 'full'. I know a full one at 70 degrees should be around 2200. Anyway I have spent countless hours trying to fuse two pieces of aluminum together without success. Got a dedicated stainless steel brush, acetone, played with all the settings etc... Using 2% lanthanated 3/32 electrode. 120 hz on the frequency, cleaning on 30%.
about 120 amps on current setting, electrode neg., pre-flow on 1 sec, post on 8. Sure I've dipped the tip more times than I care to remember trying to get the hang of this, but it just seems more difficult than it should be. I have had A Lincoln mig welder for 30 years now and a stick welder for ten that I am pretty good at making a good looking and strong weld. I tried it on dc doing some soft steel and it works much better and the arc is more stable. Had someone shut off my gas at the tank mid-weld to just see the difference with gas and then no gas and it was quite unmanageable without. I know I'm rambling here and thank you guys for reading this through but I think I have a slightly contaminated tank of Argon being it was filled the way I described. As I said...less noticable on DC doing steel but crappy on aluminum. I am able to run a flat bead of 4043 on some 1/4" plate but that's about it. Anyone have any thoughts?

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