Contaminated Argon Or Something Else?

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So by now Ive spent the better half of two days trying to troubleshoot why suddenly after the weekend I can't even get a puddle on steel, and barely on alum (but with what looks like no cleaning action with no frost along the bead).I'm on bottle number three from laurel bottled gas with the first of 3 so far being fine. After squelching any airleak I found and using brand new tungsten on decently cleaned base metal and still getting junk I thought maybe the gas. It's happened before to folks so I go and get the bottle exchanged but still have the same issue. I will point out that the arc is more stable now versus the prior bottle as alum will form a puddle before slagging up. Steel will just spit and sputter leaving a porous mess still. Filler metal will immediately ball and oxidize if added on alum.Htp invertig 221For alum ss brush cleanedBalance tried from 65 to 75Freq from 90 to 120Gas from 12 to 20 no change4043 alum fillerEr70s6 for steelTungstens lanth and ceriated 1/16 to 1/8th6061 alum and mild steel baseI checked the gas for any co2 smell and haven't had my tungstens explode in a ball of fire as with migmix (although I get sparkle from mild steel even with a new tungsten ground on a new wheel)I'll snap some pictures of what Im getting in a sec.There are only 2 things I know of that changed between earlier and now. New cylinder and I tried out the stick mode for the first time. Going to open the machine up and check the onternal hoses and the solenoid. It's rare, but I've seen a few leaky noids in new machines.Any help is appreciated, this is driving me nuts  Attached ImagesLast edited by Commodore8888; 03-27-2012 at 06:44 PM.HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG
Reply:Make sure your torch is on the netative, and on ground the positive terminal.
Reply:Did you maybe change the polarity for stick and forget to change it back for tig?
Reply:Definitely have the torch and ground in the right dinse sockets. Easy to remember on this machine as the gas hookup is right next to the negative. DC didn't cause the tungsten to melt down (was thinking maybe polarity got reversed in the machine or something?) so I'm  certain this was all done on straight polarity for the steel. Saw someone do it with high amps once during an internship. Tungsten turned into a sparkler and vaporizedOpening up the machine as we speak. I'll be keen to check for anything out of the ordinary and that solenoid is getting windex checked.HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG
Reply:Do you have a differnet welding shop you can exchange your bottle of argon at?  Maybe they have a whole batch of bad gas at the place you've been going to.
Reply:That's a thought that has crossed my mind. When I swapped the bottle the guy said it was from a different batch number that airgas had dropped off. Maybe something in the depot's lines screwed up a bunch of tanks. Granted that seems a little unlikely...but not impossible.There's a 250cu left over from the internship still in the old lab. I know that gas was good from before spring and that I left it with 3/4 full minimum. I'll check to see if it's still there and if so try to go run a quick bead with it. Tempted to have a little 20cu around as a "control" tank if this ends up being bad gas.The other place I know of for Argon fills is Roberts Oxy. They are super close, but they wanted $65+ for an 80cu fill O.o.I'll have to look around and see what I can find. Granted...the tank I got this time has ROB-OXY stamped into it. Go figure.Edit////Just got done putting everything back together. Checked for leaks and reseated everything. Popped the torch head off the cable, hooked it into a pressure gauge, and pressurized the entire system tank to torch. No PSI drops and no flowmeter movement or "gas noise". I guess I can rule out gas leaks and I already pressure tested the torch to be safe. That leaves metal/tungsten/gas contamination or a week old machine going on the fritz :/Last edited by Commodore8888; 03-27-2012 at 09:14 PM.HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG
Reply:Still sounds like a bad gas problem to me.Almost bought one of those HTP units a few months ago.  I think they are a bargain.
Reply:That's what I was thinking. The tank I've got sitting around atm is just an 80 and I figure it's much more likely the average owner of that kind of tank would leave the valve open after running it to 0psi. Then I guess you get the fillers who either won't see that or don't care and don't purge the tank. End up filling a tank that moisture drifted into with an open valve + no reg. That or they have a faulty line at either the depot or shop.At this point I'm pretty much convinced it's the argon. Between classes today I spent lunch looking at other "Tig Problems" threads. A couple jumped out as having the identical problems in their pictures (Contamination, no cleaning action during DCEP cycle leading to the arc going nuts all over the metal, etc). Look at the bottom of the threads and most all came out to moisture in the tank. Good news is I found that 250cu cylinder still in place at GSFC so that's a lucky break. Still 3/4 full too. Guess I'll go check using the Goddard tank and then drop off that 80. I'll be sure to bring a coupon with beads from both tanks in case the shop ends up giving me trouble. Can't argue with nasa argon though. BLDG 5 tests everything that comes in and even a hint of something wrong and it leaves on the truck it came in on.HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG
Reply:Originally Posted by Commodore8888T Guess I'll go check using the Goddard tank and then drop off that 80. I'll be sure to bring a coupon with beads from both tanks in case the shop ends up giving me trouble. Can't argue with nasa argon though. BLDG 5 tests everything that comes in and even a hint of something wrong and it leaves on the truck it came in on.
Reply:Sidney as in Sidney Mc clure? Before my time, but my father has been with goddard for about 20 years now and he says he remembers the name from when he started there as a tech with integration. Mark Mann is the guy who got us setup for Tig over the summer; runs the aerospace welding lab now. Funny when pops and him met again both made jokes about not recognizing each other due to grey hair. I know I'll get nailed with that eventually It's neat how so many folks who work there stick around for so long. I forgot the name, but the same guy my father would pick up reamers and taps from 15 years ago was the same guy working the tool lockers when I needed them for our bot chassis. Nice bunch who helped us out and Mike Comberiate(EE ret.) and I would return favors when ever possible. Still trying to keep as much contact with those guys as I can. Many years of experience and good info in addition to being pretty good friends. Not a bridge I'd ever think of burning and believe me, I know about the stringency of building. We had a single shot for our project so it was design, measure 4 times, set up, measure again 2 times, then make the cut, recheck some more, etc. Helped us fart out a working bot for Greenland in 8 weeks flat from drawing board to ice sheet. Pulled more all-nighters than I'd care to admit haha.-------------------------------------------------------------------------------------------------------------------------------Probably should have stuck this at the top of the post, but, turned out to be the gas after all. Moisture contamination. Knew I wasn't going nuts lol. Laurel Gas has been real patient with me and I'll have to return the favor with plenty more business (provided airgas quits dumping crap tanks on them). I'll have to give them a ring tomorrow morning and give them a heads up that a few batches from airgas look to have been borked so they don't end up having to go through this with someone else that could be less understanding or relies on welding as income.Now back to what I was trying last Sunday...Soda Cans...we meet again.HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG
Reply:Sweet... glad you figured it out!