TIG problem - Porosity!

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I recently faced a problem with my TIG welding, a problem that i never had before. I get posority out of my TIG welding with no apparent reason. My current setup is:Pure Argon gas, a Chinese but very good DC TIG welding machine, 1/16" tungsten (red), 1/16" and 3/32" ER70S-6 filler rods. Here is what i got: I decided to grind off the affected arear and start again: You can see that posority has gone quite deep into the base metal! I tried again, and the result was better but still porosity is there. It like the area is infected... In other arear the weld is OK, weird... Any ideas? Thanks a lot!
Reply:Just go down the check list,make sure you have enough argon flow , make sure you steel is clean,check your cup for obstruction or cracks, check for and argon leaks. (shut off your rig and if the ball in your flow regulator dont drop you got a leak some were.check for wind or draft. check your wire for any oil or dirt that may be on it. hope this helps
Reply:The heavy red rust looking areas in pict three would lead me to believe you dipped your tungsten. If you fouled the tungsten and didn't remove all the fouling, that may be one issue.A second issue might be bad gas if you just changed the cylinder out. However if you are able to make the weld shown in pict 4 after the poor welds, then my guess is the gas isn't your issue. Then I'd start looking at the material you are using in the problem area as the most likely cause of your issues.Last thought might be that you are loosing shielding due to the way you have your torch angled. Round items, especially small ones, are fairly difficult to swing the torch around and maintain proper torch angle relative to the work surface. I often see guys who will make "straight" welds on round surfaces, where they will not swing the torch properly. That means they often end up with long arcs and possibly poor gas coverage, or may be pulling in air because the torch is no longer pointed at the weld and you are creating a venturi effect. This might explain why you can make nice beads on straight runs, but are getting porosity on the round one.A few questions...1) Did you make the welds in pict 4 BEFORE or AFTER the problem welds shown?2) How did you prep the material in the problem areas and what sort of material are you using? Some times "salvaged" or repurposed" materials may be oil soaked and the contaminants are buried in the material itself or the material may not be what you think it is.3) Did you recently change your gas?4) Have you tried a new clean tungsten  not just one you reground a bit? Fouling can often go quite far up the tungsten and regrinding may not remove it all.5) Can you make nice clean beads on some other pieces of similar sized round material?.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:Originally Posted by DSWA few questions...1) Did you make the welds in pict 4 BEFORE or AFTER the problem welds shown?2) How did you prep the material in the problem areas and what sort of material are you using? Some times "salvaged" or repurposed" materials may be oil soaked and the contaminants are buried in the material itself or the material may not be what you think it is.3) Did you recently change your gas?4) Have you tried a new clean tungsten  not just one you reground a bit? Fouling can often go quite far up the tungsten and regrinding may not remove it all.5) Can you make nice clean beads on some other pieces of similar sized round material?
Reply:Your porosity issue to me shows lack of shielding gas coverage.I was dc tiging a steel stand for a xmas decoration for my wife yesterday. It was a round weld around a cup (just like yours). I was holding my torch with my fingers on the gas valve (I use a torch with valve) and as I was working my around the tube, the gas valve was slowly shut off just from me holding it in this position. I quickly developed porosity identical to yours in this location. It was from lack of gas shielding and incorrect torch angle. Too long of an arc will also cause lack of shielding when tig welding.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:The contaminate are coming from the inside of the tank.  Tigging over a hole.
Reply:I forgot to mention that the problem does not occur only on this part but randomly!Look here. While i was welding perfectly, for no apparent reason the porosity hit back again! [IMG][/IMG]
Reply:Double postLast edited by shovelon; 11-08-2012 at 11:16 AM.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:All of the conditions mentioned above apply, but I do see a clue. Your first pic shows a bung with little profile to hold in the cover gas. The second pic shows a fillet with plenty of side material to hold the gas long enough to complete the weld without bubbles.This indicates to me clean gas, but either too much gas or too little gas. Too much is self explanitory. Too little means hole in gas line, hole in backcap, pinched gas line, crushed collet, bad o-ring on backcap, ect. I like to check the torch first and go back from there.First thing I do is check CFH at the torch versus flowmeter with a portable flow checker. If there is a difference I then crack the backcap, pull out the collet body and collet and look to see if the backcap is closing off the gas port. If so that could be wrong backcap, crushed or twisted collet or worn out collet body. If those are good I move onto the backcap and gas hose. Somewhere along the way is the problem. It could even be a failed flowmeter. I have had the glass ball tube o-ring crack and leak gas out the top. I have had the plastic view case crack and loose gas too. Best thing I bought in years is the portable flowchecker. I have on at every tig station. You get the good ones at www.netwelding.com/prod02.htmWeld 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:So how should the flow be adjusted for a given joint(the bung).  What type joint is the third photo?  Could it be change of torch angle as he moves?Last edited by tapwelder; 11-08-2012 at 11:36 AM.
Reply:Originally Posted by shovelonAll of the conditions mentioned above apply, but I do see a clue. Your first pic shows a bung with little profile to hold in the cover gas. The second pic shows a fillet with plenty of side material to hold the gas long enough to complete the weld without bubbles.This indicates to me clean gas, but either too much gas or too little gas. Too much is self explanitory. Too little means hole in gas line, hole in backcap, pinched gas line, crushed collet, bad o-ring on backcap, ect. I like to check the torch first and go back from there.First thing I do is check CFH at the torch versus flowmeter with a portable flow checker. If there is a difference I then crack the backcap, pull out the collet body and collet and look to see if the backcap is closing off the gas port. If so that could be wrong backcap, crushed or twisted collet or worn out collet body. If those are good I move onto the backcap and gas hose. Somewhere along the way is the problem. It could even be a failed flowmeter. I have had the glass ball tube o-ring crack and leak gas out the top. I have had the plastic view case crack and loose gas too. Best thing I bought in years is the portable flowchecker. I have on at every tig station. You get the good ones at www.netwelding.com/prod02.htm
Reply:Since I am not a good welder I need to ask, it looks like he is really heating up the plate and the fitting in order to get a puddle.  If he does not get enough heat on either side their will be poor fustion, trapped gas and his welds look like he could use a larger filler metal, along with a larger tungsten and cup, I would say he needs to focus more heat and faster, floor your foot control with your higher amps and get a puddle faster, similar to aluminum and concentrate on the thicker of the two pieces.
Reply:I have encountered similar issues, occasionally,when I install interior handrails.  I have completely ground welds out and still get same porosity.  Tried cooking the metal so see if it burns out.  Tried adjusting torch angle.  Still haven't figured the issues. I deal with tubing mostly,  thought it could be oil coming from inside tubing.  Perhaps...A couple of weeks ago I did checked all my connections for leaks.  I did have a  couple of leaks.  Still have a tiny one at the cylinder even after replacing the fitting . Thought I could be pulling something into/ through the line.  Haven't  Tigged anything to test it.  Anyway,  I will be interested in you solution.
Reply:I've just made a test with soapy water and there is indeed a leak at where the backcap meets the torch body!It's not a severe thing but there's certainly a leak.Do you think this will cause all the problems?
Reply:It could however I would think that if it leaks and is aspirating air that all the welds would have problems unless you are running at different CFH.  The back cap should have a red "o" ring where is connects to the torch body.
Reply:I had similar problem. I found out it was a leak. Check all tubes and conections from bottle to torch.
Reply:Originally Posted by TheoI've just made a test with soapy water and there is indeed a leak at where the backcap meets the torch body!It's not a severe thing but there's certainly a leak.Do you think this will cause all the problems?
Reply:In the picts you posted I noticed that in 3 of them your porosity is proceeded by, or accompanies a rusty looking "haze" around the weld. That typically is an indication that you dipped the tungsten and fouled it. .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:@DSW, I would hope that was the case but in fact as soon as i was approaching an arear that was previously porous, the weld pool was boiling and making large craters. I think the area has been contaminated at the first pass.
Reply:I helped tig weld part of a commercial fryer last month. Even though they had cleaned it "thoroughly"  there was still a lot of oil/grease that they couldn't get to deep inside the hollow pieces of the burner assembly. As soon as the piece heated up and the oil/grease started to flow, POW, you'd get a section of weld that would blow out with porosity... Stop, regrind the tungsten to clear all the fouling that had just blown all over it, grind out the bad section , reclean and try again. Most likely knowing you'd do it all over again almost as soon as you got started...If you tried to just ignore it and keep going without regrinding and cleaning, ( like the original guy was trying to do) you'd get what you are describing. Many times the weld would go back to being fine, but if you tried to weld over the bad section, you'd have problems that would continue to surface again and again..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:I grinded the bad sections, but as you cann see at the 2nd picture, the porosity has gone deep enough and into the base metal. The result after grinding it was better but the problem was still there.Proper cleaning is the way to go. But i think that in this case, dirt/oil was not the cause of the problem. I tried to weld on several other places perfectly clean (and tacked already with n problems) and i got the same problem!
Reply:are you using an air cooled torch? if so are you using a gas lens? I had a similar problem with my dynasty I added the gas lens and it went away,
Reply:Originally Posted by gateheadare you using an air cooled torch? if so are you using a gas lens? I had a similar problem with my dynasty I added the gas lens and it went away,
Reply:Originally Posted by gateheadare you using an air cooled torch? if so are you using a gas lens? I had a similar problem with my dynasty I added the gas lens and it went away,
Reply:I've just found out the my collet body is 2.4mm while the collet and tungsten are 1.6mm (1/16").... Any real problem with that?Originally Posted by TheoI've just found out the my collet body is 2.4mm while the collet and tungsten are 1.6mm (1/16").... Any real problem with that?
Reply:First time poster, 30 plus years of industrial welding experience.I would check it this way:get a separate piece of steel, grind a clean spot, then run some dry wash beads - no filler wire. that'll tell you if the problem is the gas or a leak, personally I don't believe leaks cause porosity, but I'm using company argon, so my leaks would be blowing out, not sucking in. Make sure all your connections are tight.If that comes out OK, then add some wire. I've come across bad wire occasionally, but it wouldn't bubble up quite that bad.More that likely you have contamination in the steel you're trying to weld.Also, I gave up using straight cups in the early 80's, always use a gas lens.
Reply:A gas lens will not solve anything unless you need a long stickout to get into some deep joints. I did have a problem once when the hose going from the gas solenoid to the torch got burnt inside the machine, and drove me nuts for about a month.I hate being bi-polar it's awsomeMy Heroes Have Always Been Cowboys
Reply:Originally Posted by weldermikeA gas lens will not solve anything unless you need a long stickout to get into some deep joints. I did have a problem once when the hose going from the gas solenoid to the torch got burnt inside the machine, and drove me nuts for about a month.
Reply:The gas diffusers on air cooled torches are like an inch from the front of the cup. With a gas lens it is like 1/2".
Reply:First of all thanks for all the help and tips. All of you! Although my collet doby is 2.4mm (3/32"), the collet holder is 1.6mm (1/16") and keeps the tungsten totally tight. So, no problem with tungsten droping into the puddle. I've already checkes all the gas connections (except inside the machine) and there is no problem, except one pretty slight leak at the backcap. My torch (WP-17) has a teflon insulator at the front of the torch (between torch and alumina) but not at the back of the torch (between torch and backcap). I've seen some torches with back insulator and others without one. Another thing here. At the last bottle refill and prior sending the bottle for refilling, i made the "mistake" (?) to open the bottle valve to totally empty the gas. Do you think this let some air into the bottle which was impossible to extract during refilling and trapped inside with the argon gas?? @TimmyTIG I will check the test you are describing, but generally what i have noted so far is that when i am tigging without a filler rod the base metal boild and when i add rod, things get a little bit better. Tungsten sticks out about 4-5mm maximum. I am about to buy some gas lens. I've found a dead ch(eap)inese one from ebay here: http://www.ebay.com/itm/TIG-WP-17-18...item5d2e790f68 Do you think it's any good? Anyone used this before? Thanks again!
Reply:You do a leakdown check yet? Put a backcap on both sizes of the torch and turn on the argon, then turn it off and watch the gauge. If the gauge shows the pressure is getting lower find the leak and fix it. Connections are not the only places to check, check the hoses also.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:I have a funny story about tig torch porosity. I was in a shop long ago and trying to weld a simple 2" sch 40 buttweld, I kept getting porosity left right & center. No matter how clean I would clean the metal, I had excellent flow coverage, my gas lens was brand new, good size cup, and porosity, porosity, porosity!! So, I pulled my foreman over and we couldn't figure it out, so he got the super. Now our shop superintendent is an insane tig welder. He welds everythingFrom carbon to titanium and I've seen his Inconel root pass and the ripples are so consistent, it looks like a machine welded the pipe. Anyways, so he comes over and checks the whole setup. So he strikes an arc on one buttweld and suddenly it's porosity, so he's like "this is a bad weld, cut it out and we'll fix it. Then he strikes on another butt weld, with same results, and he's like "this butt weld is also bad.. Cut it out and we'll fix it!" then he tried striking the torch on a simple piece of metal and porosity like crazy. Anyways, my welds weren't bad for causing porosity, it was a defective torch. Bit it was funny because every thing he touched with that defective torch would cause porosity and he'd be like "hey! This is a bad weld too! (and this one is bad, and that one us bad.. I'll strike up on this one - porosity! Cut this out, it's a bad weld too!)" lolAnyways, that was a funny day - Replace the tig torch, hose and all tig parts in the machine. You may have a defective torch, defective parts within the torch (collet body I.e) you may have a tiny little pinhole in the torch hose that is sucking in air and supplying your weld with contaminated air - or check that the hoses are secure and tight at the back of that machine. Sometimes with those copper fittings you could have them tight and you may have to back them off just the tiniest of amount so that the threads are fully locking together and that you get a seal.I would also turn your torch purge up to 25 or 30. Butt welds in the shop we turn them up to that. I seen a guy use 15 on the torch and he would scream if someone opened a door cause it would blow his shielding gas away. That guy was nothing but a hack MickeyMouse caveman welder. He ducktaped a pencil grinder to a broom stick and kept that close by. Didn't know how to fix anything. Terrible.46’ sae30047’ sa200 w/Wisconsin VF451’ shorthood56’ shorthood56’ shorthood68’ redface69 redface07’ ranger 305G13’ sae300Inconel/Hastelloy – SS – Duplex – Chrome/Carbon Tig – F3Downhand – STT/RMD – F3F4 – B Pressure
Reply:Well, now I'm thinking it's bad gas or a leak if you bubble up on dry wash beads. You probably got sold carbon dioxide instead of argon. I was on a stainless job once where they weren't using liquid argon, no matter what we tried the beads inside the pipe were black. Finally put an oxygen analyzer on it and every bottle was 2 % oxygen, so you can occasionally get bad gas.Last edited by TimmyTIG; 11-12-2012 at 11:05 AM.
Reply:You definately should not use a 3/32" collet body with a 1/16" collet. The collet will drop down into the opening and allow the backcap to close off the gas port.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:Something I was wondering about the bung is could it be made from 12L14(leaded steel)?But seeing as he has a similar issue on the tube that may not be the case.
Reply:As long as everyone is taking a guess, I notice the porosity seems to be at starts/restarts and then clears up.  Is your gas, 'solenoid controlled' or by 'torch valve'?  Any chance of the solenoid sticking or delaying flow.   Do you know that once there is any sign of porosity in a tig weld, it must be completely ground out?  All the bubbles in your second picture have to be completely eliminated.  Sometimes you can bury porosity but you'll never burn it out.  I've never used foot-pedal/solenoid torches so don't know their workings.  Can you free flow the gas somehow to guarantee it's not the problem?