TIG welding thin stainless

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So - I got myself a chinese TIG welder, leathers, helmet etc. Up till now I have been doing O-A, but since I moved, and have much less room and the wife was a bit afraid of open flames etc. - I am trying to teach myself to TIG. I do RBSs (rolling ball sculptures). This is a hobby, not a profession.I did some thick-stainless practice welds, and though definitely not perfect, they seem ok. but - when I try thin stainless - 12-gauge wire, thin-walled (1/32) tubing,  especially with tubing, but with wire as well, no matter how low I set the amps and how sharp I make the 1/16 electrode, the heat just blows right through the steel. It takes literally a fraction of a second to make a hole or to ball-up the end of the wire.I need some help - what are the techniques you guys may suggest that would prevent this from happening?
Reply:More info needed to be sure (amperage? is the machine scratch start, lift/HF start? Remote amperage control or are you using slope controls with a basic torch button?) but...Sounds as though your torch and filler angles are wrong and/or arc length is excessive. There's a TIG welding guide >here< and somewhere in it there's diagrams showing the proper torch/filler relationship for different jointsArc length should be no more than the tungstens diameter, preferably closer to 1mm/0.40" for thin stuffGood (daylight tight) fit up is essential for thin stuff, especially stainless, with lots of tacks to maintain the fit
Reply:What kind of machine did you get? Are you using a footpedal? Are you blowin holes in it as soon as the arc is struck?If you can get an arc going, and start welding and then blow holes, try backing off the pedal slightly as you go, on something that thin you will need slightly less heat input towards the end than at the begining. This is assuming you have control over your amperage while welding.If you are just blowin holes immediately when an arc is struck, see if there is a way  to lower your start amperage, you may not be able to do this with your machine.Tell us more about your machine etc....Yup
Reply:Switch to streight polarity (DCEN).  JGSMAW,GMAW,FCAW,GTAW,SAW,PAC/PAW/OFCand Shielding Gases.  There all here. :
Reply:Originally Posted by TerrSo - I got myself a chinese TIG welder, leathers, helmet etc. Up till now I have been doing O-A, but since I moved, and have much less room and the wife was a bit afraid of open flames etc. - I am trying to teach myself to TIG. I do RBSs (rolling ball sculptures). This is a hobby, not a profession.I did some thick-stainless practice welds, and though definitely not perfect, they seem ok. but - when I try thin stainless - 12-gauge wire, thin-walled (1/32) tubing,  especially with tubing, but with wire as well, no matter how low I set the amps and how sharp I make the 1/16 electrode, the heat just blows right through the steel. It takes literally a fraction of a second to make a hole or to ball-up the end of the wire.I need some help - what are the techniques you guys may suggest that would prevent this from happening?
Reply:Originally Posted by hotrodderMore info needed to be sure (amperage? is the machine scratch start, lift/HF start? Remote amperage control or are you using slope controls with a basic torch button?) but...
Reply:Originally Posted by BurnitWhat kind of machine did you get? Are you using a footpedal? Are you blowin holes in it as soon as the arc is struck?If you can get an arc going, and start welding and then blow holes, try backing off the pedal slightly as you go, on something that thin you will need slightly less heat input towards the end than at the begining. This is assuming you have control over your amperage while welding.If you are just blowin holes immediately when an arc is struck, see if there is a way  to lower your start amperage, you may not be able to do this with your machine.Tell us more about your machine etc....
Reply:Followup - there is no way to switch polarity on this welder   I tried the hold-electrode-real-close-as-you-startup thing, and it helped matters a bit. You still have to be awful quick with the weld otherwise holes start appearing.... Basically it's like spot-welding. Running a bead is almost impossible unless you're very precise and quick (at least more precise and quick than I am).I may get a pedal and see if it helps... For now I switched to thicker-wall tubing and that really helped.
Reply:Originally Posted by TerrAmperage is 0 to 200, I set it as low as 10, still same result. It is HF start, and it is a button-on-torch control...So I should bring the torch in to 1 mm distance THEN press the button? There is no preflow control - would the start of flow of gas be quick enough to prevent oxidation?
Reply:I'm pretty new with all of this as well, but it seems that the 1/16" electrode is probably a big part of the problem.  For something that thin you probably need an .020 electrode.  I tried messing around with some .020 sheet aluminum using an .040 electrode and had the same thing happen.  No matter how low I set the current it would just instantly vaporize the sheet I was welding on.  I didn't have the .020 electrode so I couldn't prove the theory, but I think that too big of an electrode was the problem.  Good Luck,Rene
Reply:A finer tungsten isn't going to make a huge difference- too large a tungsten can result in arc wander at low amps but i can weld 0.5mm stainless with a 1.6mm without problems. I believe that some of the members here (Engloid?) never bother with anything smaller than a 2.4- just grind a very fine pointTerr, your linky no worky. Inverters rarely have a polarity switch- swap leads around for SMAW, TIG is virtually always DCEN or AC. No preflow adjustment, again not a big deal as long as there is 0.5 sec or so as a fixed preset- if you need more you can activate the postflow before arcing upThin stainless, you do need to be quick and accurate- nature of the beast i'm afraid. Did you try Rojo's suggestion of arcing up to the side of the joint?  A poor fit combined with a 'harsh' HF could blow a hole- i sometimes use Rojo's trick if i'm using scratch start on thin materialDoes your machine have 'slope' controls and/or adjustable starting parameters? It's fairly common to be able to set starting amperage as a percentage of welding amps, slope up is the time in seconds taken to reach welding amps
Reply:I made up one small tuned exhaust pipe recently with <24ga stainless. Fit had to be perfect to avoid burnin the edges away from the puddle. 1/6 in electrode was fine with it sharpened to a fine point. 1/16 filler was a bit big, found stainless mig wire did a better job for filler, but its hard to feed in consistently. Set to 50 amps and used foot peddle about half way.
Reply:Originally Posted by hotrodderTerr, your linky no worky. Inverters rarely have a polarity switch- swap leads around for SMAW, TIG is virtually always DCEN or AC. No preflow adjustment, again not a big deal as long as there is 0.5 sec or so as a fixed preset- if you need more you can activate the postflow before arcing up
Reply:Terr, my advice now that I have all the info on your machine is to just practice with it. You'll get pretty good after a while. And, then comes the sweet part....someday, you'll get your hands on a welder with a lot more adjustability and much finer/ more precise controls. And when you get on a machine like that, and you have been making due with what you have, you are going to make welds that will FLOOR you. And it will seem sooooo easy, you won't believe it.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.