TIG welding SS - what am I doing wrong?

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I'm new to TIG welding, and to my machine.  It's a Lincoln V160-T.  3/32" 2% thor, 1/16" 308L filler.  I'm still just practicing beads across some 16-gauge 304 tubing that I have laying around.  My beads seem to be sunken in and I get alot of sugaring in the inside.  This is with about 60 amps.  My first thought was too much heat.  But if I reduce amperage, my filler sticks to the puddle.  I'm not really sure what I'm doing wrong.  Can anyone give me some advice on what to do differently?  Thanks in advance."There are two types of people in America - those who try to classify everyone into two types and those who don't."
Reply:There could be many things going on, but you are close. Keep your filler rod in the gas stream. Make sure you are not picking up contamination from the backside. Use proper diameter cup. Make sure the gas is getting to the torch head, Check to see if the backcap has a hole in it. Could be some suspicious or bad gas. Try some smaller rod perhaps.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:A bit more heat and move faster. Backpurge or solarflux for the back side to help on the sugaring/weld sinking. One more dab and little circles as you EASE off the pedal to help on the crater at the end of your weld. And for that size material i'd lose the 3/32 tung and go with 1/16 or .040".Last edited by Malave16; 01-14-2012 at 10:42 PM.
Reply:Grab some MIG wire - like .035 and use that as a filler.  That will allow you to turn the amps down.  I have no idea how accurate my digital gauges are, but once you get going, 45 amps should be enough.As for sugaring on the back side.  If you weld all the way through, it will sugar if you don't protect it.  Since you say it sunken in (and you are adding filler) you are definitely going all the way through.  You have to do something or the weld will look like crap (it will also gray more easily on the front side!)On the top bead, is that rust color around your stop?  Make sure you hold the torch over the weld bead when you lift on the peddle.  Hold it there until either the metal stops glowing or the gas snaps off.You said you are using filler, but either you are running way too hot, or way too slow.  I would expect to see evenly spaced 'puddles' stacked right next to each other.  What I see are ripples that look like you just moved the puddle.One last thing, when you 'practice' make the beads longer than say 2".   At 2" inches you are barely moving the torch and not repositioning the filler.  You'll end up getting into bad habits.   Scratch a line down the piece you are welding and follow that line.When you practice, you want consistency more than beauty.  Consistency means you are under control, that includes moving the torch even steps and adding he same amount of filler each of those steps.  Once you are consistent, you can tweak what you are doing as necessary to make it beautiful.Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:For 16 ga  SS or steel, I use a 1/16" diameter tungsten, and .045 diameter filler rod.ESAB Migmaster 250 Hobart Ironman 230Multimatic 215TWECO Fabricator 181i & 211iHH125EZ - nice little fluxcore only unitMaxstar 150 STH - very nice
Reply:Hello SuedePflow, the GTAW process is somewhat different from most of the other welding processes that are commonly used. For one thing, the current that is used has a tendency to have a fairly great depth to width ratio when you look at penetration characteristics. Thus when you try to run a bead width similar to OFW, SMAW, GMAW, or FCAW, you will almost certainly end up with a much larger bead for a given thickness than is required. GTAW is also unique since you can make a weld at a slower or faster travel speed with the same amperage setting and end up with very different weld beads. The angle that you grind on the tungsten can also have a considerable influence on bead penetration profiles. A long tapered grind will provide a wider/shallower penetration profile. A short taper/angle grind on a tungsten will provide a narrower/deeper penetration profile. Do a bit of research and you will find a number of charts available that explain tungsten grinding very well. You can probably use your 3/32" tungsten and grind a long taper on it and make it work, although, a smaller diameter tungsten ground similarly might provide a stabler arc and a better match for the thickness of material you are using. One of the other posters mentioned using a smaller filler rod, as well, SS spooled welding wire, GMAW welding wire does work very well as it has the same filler wire designation and is simply spooled instead of in a rod form. The .045 diameter wire might address your issue very well, simply spool some off and straighten it out to use just like the 1/16" you've been using. Welding stainless steel with GTAW is much more challenging than a lot of other materials due to it's reactivity. You read about sugaring and such when the penetration is excessive, a number of things can be tried which might help with that. Faster travel speeds, smaller filler rod diameters, smaller bead sizes, sometimes a greater torch push angel, one or more of any one of these could likely help out. One more point about GTAW in general for other than welding on Aluminum, Magnesium, or pot metal, since bead sizes can generally be smaller in width due to better penetration to width ratios, you will likely also run reduced heat. This reduction in heat will change the size requirement for filler metals. You will want to run a small enough filler that you won't have sticking issues. If you do try to run a larger filler, you run the risk of being tempted to increase the amperage in order to melt the rod to keep it from sticking and at that point you may experience excessive burn-through or in the case of welding on stainless steel a lot of sugaring. Lay-wire techniques do not apply to what I have discussed above as the technique allows for using a larger diameter wire to lay down relatively large beads on materials without a lot of depth related issues. Good luck and best regards, AllanLast edited by aevald; 01-15-2012 at 03:46 AM.aevald
Reply:Too hot  DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Thanks for the advice everyone.  Much appreciated.I dropped the amperage to 50 and sped up my travel and I got much better results.  It's not sunken in anymore.  I was definitely moving too slow before.  I also kept the filler in the gas stream and that kept it from sticking.  I know I still need to work on ramping off slowly at the end.  If there's anything else you guys think I should be doing differently, I'm all ears. I ordered a pack of 1/16" tungsten yesterday.  Meanwhile, I put a longer taper on my current one and it seemed to help getting the puddle to started quicker.I'm wondering if my gas coverage is proper for what I'm doing?  Regulator set at 15, #8 cup, 10 seconds post flow.This is also pulsing about 200 PPM and 30% on the low end:"There are two types of people in America - those who try to classify everyone into two types and those who don't."
Reply:Just for reference, I set my flow to 20cfh with my #8 cup. Stickout would be about half the inner diameter of the cup which would put it at 1/4" because the #8 is 8/16" internal diameter.I see towards the left of the weld you have a lighter brown and more convexed bead shape. That indicates to me that you let off the pedal some and fed the rod harder. Try turning your current control down some, and feed the rod really hard on your next pass. Let the rod absorb a good deal of that heat. Also try not to burn thru, and I think you have it.Good Luck.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by shovelonJust for reference, I set my flow to 20cfh with my #8 cup. Stickout would be about half the inner diameter of the cup which would put it at 1/4" because the #8 is 8/16" internal diameter.I see towards the left of the weld you have a lighter brown and more convexed bead shape. That indicates to me that you let off the pedal some and fed the rod harder. Try turning your current control down some, and feed the rod really hard on your next pass. Let the rod absorb a good deal of that heat. Also try not to burn thru, and I think you have it.Good Luck.
Reply:About how far should I be keeing my tungsten tip from the work?"There are two types of people in America - those who try to classify everyone into two types and those who don't."
Reply:Hello Paul, as close as you can to the puddle without touching it will generally give you the best control. Good luck and regards, Allanaevald
Reply:If you can hold 1 mm off the work with the electrode without dipping thats good.  Turn your current down some more.  Dont be afraid to be moving very slowly. just WAIT for a puddle to form- make a small dip then move over 2 mm and wait for a new puddle to form - repeat.  Keep turning down the heat untill it looks like no puddle is possible- the bump it up a little.   The dip will quench the puddle heat.  keep checking the backside and comparing the heat signs on the back with how fat the puddle forms.  If youre getting bumps/melt through then back off on the heat.    you might consider turning off the pulser while you are learning.  That may be giving you too many variables rite now.  The Mig wire is good to show you how small you can go with a puddle.  You can do a weld the size of a mechanical pencil leadif you want.  barely bigger than the mig wire.  Good for practicing !
Reply:Originally Posted by jethro.  Dont be afraid to be moving very slowly. just WAIT for a puddle to form- make a small dip then move over 2 mm and wait for a new puddle to form - repeat.  Keep turning down the heat untill it looks like no puddle is possible- the bump it up a little.