[metafos]

Hi to all,

Here is a discovery I have made over the years of tig welding , something I would like to share with you all. I have noticed that when the argon tank is low( 200lbs or less) there is a contamination in the gas. The bottom of the tank holds alot of crap after being refilled over a period of time. This crap settles to the bottom of the tank, but when the tank is low, the crap gets mixed in with the argon and this creates an impure gas, thus creating poor welds. For those of you having trouble welding when the tank is near low, look no further for the problem, get a fresh tank. Hope this helps some of you guys out there playing around with your electrodes and dial settings, not knowing why your welds suddenlt turn out crappy.

[brian]

I can confirm this with you. The first time I came across this problem, couldn't figure it out. Changed everything in the torch. Finally changed the bottle, fixed the problem.

[metafos]

I checked with air liquid, they don't purge the returns, so they said that there is either water from condensation that accumulates and small amounts of other stuff. Over time, this does build up in the tank, when the overall pressure gets too low, bingo, shitty welds, unpure argon.

[tigamajig]

purging takes time, time costs money, but corporations like to save money,so
you should go to PraxAir....i believe they still have a "Purity guarantee" in effect...
...if not,change your tank and purge your torch line!