Help with tig

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Hello all, Does anyone know as to what would cause the place I stop in my welds to end up like this?I am really new to tig (last night was my first attempt) and after some good recommendations from other members I finally got to weld a slightly better results.Thanks in advance. Attached Images
Reply:Do you have a foot pedal, or remote control?It looks as if you're pulling the torch away to break the arc.  That will cause rapid cooling causing the crater at the end, and it will remove the shielding gas while the weld is still hot, causing the corrosion.If possible, you need to keep the torch over the end of the weld, back off the current while adding a little more filler to fill the crater, and allow the end to cool a little more slowly, while remaining under the argon.
Reply:I will guess, 1.   A shielding problem.  2.  No downslope on the current.The shielding on the weld in general looks like it is lacking, in other words air is getting to the molten weld pool and causing oxidation.  The cavity at the end looks like like there was a shielding problem,  the weld bubbled up full of oxygen, the arc was shut off abruptly, and there was no gas postflow.The shielding problem could result from a leaking connection at any joint within the gas system, from the gas bottle to the gas nozzle.  It could also be due to excessive tungsten stickout, excessive arc length, excessive torch angle, excessive gas flow rated, inadequate gas flow rate, wrong gas (need 100% Argon), missing "O" ring on the torch back cap, etc, etc.If you have a remote current control (foot pedal), then slowly reduce the current at the end of the weld to allow the puddle to gradually solidify.  If you don't have a remote, then try something like backing up over the finished weld and then quickly breaking the arc.What type of gas control do you have, solenoid and timer controlled preflow and postflow, or just a foot pedal activated solenoid valve, or just a manual valve on the torch?  Anyway, you need postflow shielding of the weld.I just saw your other post, http://weldingweb.com/vbb/showthread.php...586#post303586, that is terrible lack of shielding.Last edited by pulser; 07-28-2009 at 02:45 PM.
Reply:So far I have found out that I have the Argon connected to a pressure regulator that should only be used for the compressed air/plasma which I think is the root cause of the lack of shielding. All I have is a torch with the trigger on the handle so, no foot pedal.I have a postflow timer I will reconfigure the gas line and try again tonight.It is looking a lot better I have to say since my last post.Thanks for the help
Reply:ya need a set of regs.  a flow meter is best (the one with the balland yes your pulling off , like said in prev posts but most will come down to practice  practice practice