Is my argon bad or is it just me?

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I haven't done much tig welding, I weld stick at work on a regular basis for 13+ years now and I also have a nice mig setup in my garage which I use often. I picked up a miller dynasty 200dx a while ago and so far my experience has not been very good with it. For some reason I keep getting porosity. I am welding 1/4" mild steel, mill scale ground off and cleaned up, 3/32 red tungsten, 100% argon 20 cfh, #7 cup, 80-100 amps, 1/4" stick out, good angle (pushing), welding indoors, and I have a good ground. I think I may be moving slower than I should and possibly higher amps than I should hence the gray color and not rainbow. I get this porosity and when I go back to go over it the porosity keeps coming back. Only after I grind it out and try a couple more times does it go away. Sometimes I get a good weld but this porosity is killing me. Is it me or my argon?
Reply:I would think something that thick should be beveled and at least two pass it
Reply:If I remember right, in class we ran argon at 30 cfh for TIG.Try turning your gas flow up, and be sure to postflow for 5 seconds.MillerMatic 252Miller Xtreme 625Miller Digital Elite
Reply:its you, you need to grind that steel CLEAN
Reply:I would be careful going more than 20cfh with a #7 cup. Generally a #7 cup works best at 17 to 20cfh. A #8 works best at 20 to 23cfh. 30cfh and above is best reserved for a #10 to #12 cup. Too much gas is just as bad as too little. Check to see if there are any blockages that will prevent gas going thru. A hole in the backcap, missing o ring, crushed collet and so forth. Keep your stickout from 1/2 orifice diameter to no more than 1 diameter. If you use a gas lens you can play with a little more stickout. Otherwise 1/4" stickout is very good. Cleaning your base metal is a good tip. Perhaps you are using the wrong filler? If you have the correct filler, move faster with more power and cram your rod in more. Your rod should have deoxidizers to sequester the bubbles.Good luck and have fun.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 66myndI haven't done much tig welding, I weld stick at work on a regular basis for 13+ years now and I also have a nice mig setup in my garage which I use often. I picked up a miller dynasty 200dx a while ago and so far my experience has not been very good with it. For some reason I keep getting porosity. I am welding 1/4" mild steel, mill scale ground off and cleaned up, 3/32 red tungsten, 100% argon 20 cfh, #7 cup, 80-100 amps,.... I think I may be moving slower than I should and possibly higher amps than I should hence the gray color and not rainbow. I get this porosity and when I go back to go over it the porosity keeps coming back. Only after I grind it out and try a couple more times does it go away. Sometimes I get a good weld but this porosity is killing me. Is it me or my argon?
Reply:Thank you for the correction, shovelon.MillerMatic 252Miller Xtreme 625Miller Digital Elite
Reply:Thank you everyone! Hey shovelon, you ride a shovel? Thanks for the advice. This is my first Harley 1980fxwg, got about 500 miles post build (ground up) and had been making some changes lately. The piece that I'm trying to weld is for the oil filter I am mounting inside the primary. Thank you very much DSW for the informative post. Everything in that first paragraph is true. I probably didn't clean it enough. I grinded the mill scale off the edges that I was gonna weld but probably could have done a better job. There was some surface rust on the piece. I did foul the tungsten, I haven't found a good way to position myself yet to get steady uniform movement and I'm also trying to better feed the filler in. It's a little awkward using two hands. As far as welding the 1/4" steel, let say I'm not trying to fill the whole 1/4" with a fillet that size. I am using 3/32 tungsten and filler. I want to get the appropriate size weld that goes with that. I'm probably off in what size weld I think I should be making with my setup. If I were to compare it to what I do at work, I mostly weld with 7018 1/8 and in a flat I can vary my weld size from a 3/32-5/16 fillet by either running a stringer bead or giving it a little weave. Regardless of the size plate, I know how big my weld will be and that's what I'm having a hard time knowing with tig. What I'm also asking is if all these things: rust, mill scale, tungsten fouling, etc., would they all make porosity that looks just like this and be so consistent like this? Is it supposed to happen this bad even though I cleaned and prepped the steel but had not done the best job? Now I am fully aware that my tig welding skills are lacking, I have very little experience, yet I would also want to know what using a bad (contaminated) bottle of argon would do to the weld. I had originally considered bad argon in the first place as either the reason for this porosity or one of the reasons because a while back someone told me they had problems with argon from the same place I get. Is there any way I can rule out bad argon out? I am bad enough of a tig welder to begin with let alone using bad argon if that were the case. I am going to try welding more tomorrow using clean steel, and a perfect fit up along with everything else as good as I can get. Thanks again. -Ray
Reply:Bad argon doesn't come and go. The fact you get clean welds pretty much rules out the gas direct. If you had bad gas every weld you do would have issues. Porosity do to say a leak however, might come and go depending on the leak. Lack of shielding gas due to a breeze might also be sporadic. Contaminants on the surface remain even after welding many times. Just running over them again seldom "solves" the problem. Oils might tend to wick from other areas for example due to the heat and cause issues even if the 1st bead ran ok as well.As far as the smaller bead, like anything else you need to put it all in perspective. you don't need a code rated weld to hold two pieces together for yard art. So even if it's 1" material, an 1/8" bead would be fine in that application. There's just too many variables to try and sort all of that out. I usually make suggestions based on what typically would give you an acceptable bead if you were doing something to pass a test, but even then, a highly skilled welder can "work around" many things and still make acceptable welds that would pass. A weld for your oil filter isn't on the same scale as if you were welding on say the front forks of the bike..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:Thank you DSW. I'm going to check for any leaks and correct all the other things that may have been a problem. I'll post some pics.
Reply:66,Is this hidden in the primary or will the primary be open enough for it to show? If not easily visible I would just run a bead with 1/8" 7018 and be done with it.GravelThe difference between theory and practice is that in theory there is no difference.
Reply:you say the mill scale is ground off and cleaned up..look at all the rust on the lower plate..you aint grinding near enough.
Reply:If you want to rule out bad argon, get a piece of aluminum stock.  Clean it with acetone after stainless steel wire brushing.  Switch your machine to AC and use the gas settings Shovelon recommended.  Make small swirls on the aluminum with no filler addition.If the swirls are white and silver, your argon is good.  If there is a drop of black or any other color, you have bad argon or a gas delivery issue.Last edited by tigbeast; 03-30-2014 at 04:36 AM.
Reply:Originally Posted by Gravel66,Is this hidden in the primary or will the primary be open enough for it to show? If not easily visible I would just run a bead with 1/8" 7018 and be done with it.
Reply:Originally Posted by tigbeastIf you want to rule out bad argon, get a piece of aluminum stock.  Clean it with acetone after stainless steel wire brushing.  Switch your machine to AC and use the gas settings Shovelon recommended.  Make small swirls on the aluminum with no filler addition.If the swirls are white and silver, your argon is good.  If there is a drop of black or any other color, you have bad argon or a gas delivery issue.
Reply:I might have missed it being mentioned but after you grind off the rust and get it clean wipe it down with acetone.  Also don't forget to wipe your wire.  You can also get a weld that has porosity like that if your torch angle isn't correct, but I believe the prep is the culprit here.
Reply:Originally Posted by 66myndThank you everyone! Hey shovelon, you ride a shovel? Thanks for the advice. This is my first Harley 1980fxwg, got about 500 miles post build (ground up) and had been making some changes lately. The piece that I'm trying to weld is for the oil filter I am mounting inside the primary.
Reply:Originally Posted by 66myndThis is going to show but you'll barely see it anyway. I know I can weld most of what I do with mig or stick but I'm more so trying to become good at tig. I decided that I'm going to use my tig machine exclusively from now on unless I'm welding something where it would be completely impractical to use tig.  I don't want to switch welding processes because I'm frustrated and won't figure out the right way to do it.
Reply:That is what happens when you try to tig weld hot rolled steel that has now been cleaned to a polished chrome like finish.
Reply:Originally Posted by kkustomzThat is what happens when you try to tig weld hot rolled steel that has now been cleaned to a polished chrome like finish.
Reply:you didn't mention what filler you are using. I would use 70s2.70sanything would work, but it is my understanding the higher the number after the "s", the more prone it is to contamination.so say you are having your problems with 70s6, you could swap for some 70s2 and be a bit better offbosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:Originally Posted by WeldordieDoes this statement need editing?
Reply:I tried again today and you guys were right about cleaning. I only had one minor incident but for the most part I had much better results. I'm very surprised by how perfectly clean the steel has to be. It seems like a lot of time needs to be spent prepping the steel prior to welding. As a stick welder I've welded through anything imaginable so I had a hard time believing that a minor impurity would screw up my whole weld. So to all you tig pros I've got to ask, what's your normal prep procedure? What if you have to tig something on a car or something where the pieces are joined already and you can't really get in there to fully clean it? The pieces of steel I welded here were grinded clean, acetone, clamped together, and then welded. I'm curious what would happen if I clamp them together first and then clean it. Would it draw in any impurities if you do it that way? Is acetone something that you need to use to be able to tig or is that for an oily greasy environment? I understand taking many precautions but what about you guys that are production tig welders or just pros in general, I'm sure your prep is only what is absolutely necessary. Here's a bunch of pictures. I still don't have a system down for steadily moving the torch and dipping the filler in, I kind of feel like I'm just winging it. Except for the first picture with the triangle I used 1/8 red tungsten, ER70s-2 1/16, 115 amps, 15 cfh argon, 7 cup.You can see where I had porosity at the end of that weld, I didn't dip the tungsten but I'm not sure if I was too close to the weld or if there was some sort of impurity on the steel in that spot. You can see how far down the porosity is even after I grinded it out, I wasn't sure if I'd be able to weld over it but I did without incident.  The second piece was about 3" long and took me about 25 seconds to run a pass, it takes me about 5-7 seconds to initially get the puddle going. I'm not sure if I should be pressing my foot peddle all the way down for full amps right away. I also feel that I'm going too slow otherwise shouldn't I be getting a rainbow color effect after? If you look at the last picture you can see undercut. I'm not sure why that's happening.So my questions are: 1- what would be a good prep for welding on existing steel where you cannot get in between the ply where there might be mil scale, oil, rust etc?2- what size tungsten, filler, amps would you use in this situation? 3- how long should it take me to run a 3" pass and what size should the fillet be?
Reply:Pedal down all the way to start. You need all your heat immediately, you don't want to be wallowing around in one spot on carbon steel, that just invites porosity to the party. You need to keep it moving. If you need to back off, you can do that after you get going.On that, if I was at work on a wet rig I would run about 250 to 300 amps, minimum 3/32 wire, 1/8th tungsten cause that's what we use. #10 cup w/jumbo gas lens with the argon blasting.As for rainbow effect, that's for stainless. Don't sweat it on carbon.You're getting undercut because your wire is too small and you aren't feeding it fast enough.
Reply:You don't need acetone on clean steel. If you have rust and oil you probably need to use something other than TIG.Originally Posted by bandaidmdAmazing how one letter changes a post.Sent from my SCH-I605 using Tapatalk
Reply:Originally Posted by 92dlxmanyou didn't mention what filler you are using. I would use 70s2.70sanything would work, but it is my understanding the higher the number after the "s", the more prone it is to contamination.so say you are having your problems with 70s6, you could swap for some 70s2 and be a bit better off
Reply:Originally Posted by TimmyTIGPedal down all the way to start. You need all your heat immediately, you don't want to be wallowing around in one spot on carbon steel, that just invites porosity to the party. You need to keep it moving. If you need to back off, you can do that after you get going.On that, if I was at work on a wet rig I would run about 250 to 300 amps, minimum 3/32 wire, 1/8th tungsten cause that's what we use. #10 cup w/jumbo gas lens with the argon blasting.As for rainbow effect, that's for stainless. Don't sweat it on carbon.You're getting undercut because your wire is too small and you aren't feeding it fast enough.
Reply:Tungsten size- just use what you have, it's not all that critical.I would use that type of setting on carbon steel weld-o-lets, any pipe under 2 inch pipe is TIG all the way where I work.If I was welding plate like what you have there, say on a pipe shoe, I would use DualShield, just because it's faster and that's how they want it. If it was stainless we would use TIG.
Reply:Originally Posted by BrazinNope, s-2 is for clean steel, the ER70S-6 is for slightly dirty steel.Hotter and faster with good gas (about 15 CFH)  should give a shiney weld, similar to SS. But grey isn't terrible. I never clean CRS, but HRS should be cleaned an inch or so away back from the weld with 60 grit. Using 309 stainless filler can prevent some porosity, and sometimes even fix a crater without drilling or grinding.
Reply:Just to be clear the S stands for silicon, and the number is the amount, so a higher number is more. Here's from Harris:ER70S-6 (GMAW) MIGDescription: Mild Steel Welding AlloyA general purpose welding wire for fabrication of mild steel. Contains more deoxidizers than ER70S-3. The additional deoxidizers also provide better wetting, giving a flatter bead shape and the capability of faster travel speeds.SqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A
Reply:S is for SULFURSi is for SiliconAlso, the S2, S3, S6 etc. number has nothing to do with how much Silicon alone is in a wire.  It's a designation that refers to a overall composition, not the silicon content alone.S2 does have less Si than S6, but it has other deoxidizers.  Here's Lincoln's wire compared...http://www.lincolnelectric.com/en-us...LincolnER70S-6Last edited by RodJ; 04-03-2014 at 11:26 AM.
Reply:Brazin and RodJ - The "S" in ER70S-2 stands for "solid"For comparison, in flux-core wire, for E71T-1, the "T" stands for tubular.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Thanks for clearing that up Dave, just trying to keep the forum correct. RodJ-That Lincoln info says S-2 is "Triple deoxidized wire", while the S-6 is "to be used on slightly contaminated base materials". That was the point I was trying to make.Anyone use S-3? I find it a tiny bit more fluid than S-2, not sure if it's worth the cost.SqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A
Reply:MN Dave - sorry for the confusion.  I wasn't referring to the S in the rod name, that does mean solid wire, but my post wasnt clear.  I was referring to the S in the chemical analysis in the link I posted.  The S % means sulfur and the Si refers to silicon.  The S plus the number in the wire name just means solid and the number refers to the metallurgy / chemical formula.Brazin, you're correct about the uses. I have no idea how the metals including silicon work to clean things. Someday it would be interesting to find out.Carry on and happy Saturday!....  PS full disclosure.  I would characterize myself as an incompetent tig welder, but I'm too embarrassed to even say I'm any kind of tig welder. Mostly I'm just incompetent. Last edited by RodJ; 04-05-2014 at 04:41 PM.