Hooda - I really think this is something with your equipment setup, or your process. Not so easy to identify quickly or easily, but once you figure it out and fix it, you won't be looking back.
One question: Is your tungsten getting contaminated? I'm talking about the portion that is especially up by the collet body, away from the tip. If that is getting contaminated, you almost certainly have a problem with contaminated shielding gas. If that's the case, it doesn't necessarily mean the bottle of gas is bad (although it could be), it could mean that you have a loose connection, or your gas lead is introducing contamination into the gas (especially worth bringing up, since you welded at high amps without usign the cooler recently... PVC vapors into argon do not make for an inert shielding gas.) Anyhow, the way I'd quickly suggest diagnosing this: find a clean piece of aluminum. (with machine in AC, and maybe AC balance of 20% EP, and torch pointing straight into the flat piece) Make an arc, with enough heat to make a puddle. Verify that the puddle is perfectly "shiny chome" looking under the arc. No "junk" actively moving/floating in the middle of the puddle. Whole puddle clean, and shiny, nothing floating in it. When you stop, there should be no black flecks in the solidified puddle, it should have a pretty smooth texture.
If your test equipment passes that test (aluminum puddle is clean), then it's time to focus on either your steel materials as introducing the contamination, or your filler rod introducing it. You can probably guess the next step: see if you can reproduce the problem just welding (or making a deep puddle in) the base material, with no filler rod added. You just use the process of elimination to narrow it down.
If your equipment does not pass the "clean aluminum puddle" test, then you have to figure out where the contamination is coming from. One thing you can try, isyour other machine (the 185Micro) on the aluminum. If you have a different gas bottle, that could be good to try also.
One other thing you can try: test for leaks in the gas lines by reducing tungsten stickout so it's behind the cup, tightening the backcap, then press your thumb over the cup outlet tightly (so it seals it), and tap the foot pedal (make it a real quick tap though, so you don't get "zapped" by the high frequency), and after the solenoid shuts off, keep your thumb pressed down, a few seconds, then release and make sure pressure is holding in your inert gas supply system. If pressure is not holding, listen for any leaks in your torch lines, fittings, etc. Try your other machine and torch (185Micro).
If you have another inert gas bottle, it might be good time to try swapping that too. Sometimes gas bottles have contamination in them. Sometimes when you get to the bottom of a bottle, the pressure and your flowrate drops. I have experienced the gas on a bottle "going bad" as it nears emptiness before also.
Just giving you some food for thought... ideas to try. Hope you can get it figured out soon!
Last edited by jakeru; 03-17-2012 at 08:34 PM.
'13 Everlast 255EXT
'07 Everlast Super200P
hooda 
