bad contamination. cannot weld aluminium

[js quebec]

hi gang. i will try my best to explain my problem since my english is not optimal. yesterday. i was welding on aluminum to practice my welding skills. After a short pause. when i restart to weld, this appened.A big black carbon smoke around my arc,and i'm not abble to do anything.what can do that. thanks.

[Rambozo]

What are your settings? Specifically pre and post flow, balance and frequency?

[js quebec]

pre flow 3 sec.
post flow aprox 3sec.
120htz
35% ac balance

[christian]

Yeah,

You might have contaminated your tungsten from the puddle or filler. If so, shorten the tungsten, then re-grind, or just re-grind.

Or, maybe you have a sudden lack of gas coverage somehow.

Otherwise, your preflow is long and you postflow is short. If you're doing around 1/8" aluminum with about 150 amps on tap, I'd have about .5 sec. pre-flow and about 6-8 sec. post-flow, and about 15 CFH of Argon.

Please let us all know what adjustments do solve your problem.

[js quebec]

i already tried everything you mentioned. re-grind, even changed my tungstene for new one. try a new bottle of 100% argon, checked for poor ground cable. spray water-soap on all gaz line. the only leaks i found is very little one at the point where the head of my torch rotate, and the leak happen when i depress the pedal.(when the pressure is more high). here is picture of weld ive done just before the problem happen.sorry for the very bad quality but you can clearly see the weld without big black carbon. i think it s a problem with my welder, because this happen sudently

[christian]

Yeah,

How about you post some photos of some more beads on the work piece, then the TIG torch with its tungsten tip ground to a point along with the amount of stick-out you routinely use.

What cup size and gas flow rate?

Now, when you say after you "restarted" you then had the problem could suggest that your machine might have reverted to a memory setting other than an AC one, i.e., is it on "AC", or is the polarity set wrong.

How about you post a photo of the panel and settings of your particular Everlast model.

If the macine is new, I doubt that it has a problem.

i already tried everything you mentioned. re-grind, even changed my tungstene for new one. try a new bottle of 100% argon, checked for poor ground cable. spray water-soap on all gaz line. the only leaks i found is very little one at the point where the head of my torch rotate, and the leak happen when i depress the pedal.(when the pressure is more high). here is picture of weld ive done just before the problem happen.sorry for the very bad quality but you can clearly see the weld without big black carbon. i think it s a problem with my welder, because this happen sudently

[performance]

Bad Gas. Contamination. Breeze. Using the unit on the table where you are welding and the fans are blowing off the shielding gas. Whatever the cause, Carbon is from contamination, not from the welder itself.

[Marmoset]

also make sure its actually weldable aluminum, and don't forget to brush and clean the aluminum itself as well. looks a bit also like oxides just cooking on top of puddle.

Barry