Noob, struggling with TIG

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Hi everone.I'm trying to learn to use my recently purchased Lincoln square wave 175.  As I expected, I am constantly re-sharpening my Tungsten.  My arc does not stay focused at all once the point gets deformed.  I don't understand why it keeps losing its shape?  I'm careful not to contaminate it.Its like the 100amp max current is too much for the 3/32 electrode, causing it to melt.  Maybe I need to try a smaller cup  - I'm running 15 on the Argon flow.Any suggestions?Thanks,Walt
Reply:What type of tungsten you are using? Which polarity on DC or are you running AC? My first thought is that it's probably one of those two issues.With DC neg and red, orange or gold tungsten 3/32" you should have no issues keeping a good point unless you are dipping the tungsten..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Details:DC neg3/32 Blue Tungsten (Lanthanated?)100 amp15 fph Argon1/2" ID cup1/8" mild steel
Reply:Inadequate inert shielding will cause rapid oxidation and deterioration of the tungsten.  Even if you have the wrong tungsten (pure, green tip), or the wrong polarity (AC or DCEP), the tungsten would tend to melt back into a ball if supplied too much current, but it would remain shiny, clean, and smooth because it has been heated/melted in an oxygen/nitrogen free environment.  If you have an inert gas shielding problem, such as a leak somewhere between the gas bottle and the gas nozzle, air can be introduced into the arc, and you have a problem.Other considerations: The wrong gas, such as a MIG CO2 mix.  A strong breeze disrupting your shielding.  Excessive arc length (over 1/8") or excessive torch angle.
Reply:When I first got my tig welder, I didn't have enough post flow on the gas. The tungsten was turning black. If you're seeing black tungsten, you don't have enough gas. Does it stay silver-ish, or is it changing color?Is the surface clean? Rust and galvanize compound have caused issues for me as well (popping in to the electrode). Lastly, you're sure the torch is hooked to the negative, and the clamp to the positive?The soldering toys pay for the welding toys.Hakko 928 dual iron, 4xHakko 936Madell 850D Hot Air SMT ReworkMiller 252, HTP Invertig 201 AC/DC, and a Hypertherm 45.
Reply:You're not extending the tungsten too far out I hope. Double check theat you're getting good gas flow, get it going and see if you can feel the post purge. It's gotta be a purge gas problem or the polarity for what you're describing to happen. I run 3/32 tungsten up to 250 amps with no problem (though I do question the calibration of my welder sometimes). Where'd you get the tungsten? Lanthinated should be gold I think.
Reply:Thanks for all the suggestions.  Its working like a gem now.As everyone thought, it was a gas flow issue.  I tightened the connections, increased the flow another 5 cfh, and changed my cup from 1/2 to 3/8 ID.  After this the Tungsten holds up fine.I appreciate the help.Walt