TIG Aluminum FNG - Contaminated filler rod problem?

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Hey all,I'm using a Miller Diversion 180 to learn how to weld Aluminum, and right now I've been working with 1/8" 6061 stock I picked up locally. Today, I was doing some basic weld joints with both 1/16" and 1/8" 4043 Electrode and had some rather bizzare behavior. Some of the times, I would get a good bead and work on getting the stack of dimes look and it was okay. As I travelled though, I would suddenly get this kind of "crust" on the puddle and my weld goes to crap. When I remove my torch, it looks like the kind of crap that shows up from second rate castings; a black crud that gives the joint a bubbly cauliflower look. (And it's very different than when I contaminate the actual TIG electrode!) So after a somewhat disappointing day of practice, I said screw it - it must be the base metal.  I decided to try and run a bead without filler... It produced the most elegant and clean looking welds on Aluminum I've ever made - even if it ate into the base material by a lot. So this makes me scratch my head - is it possible my aluminum filler rod has "issues" or is there some other FNG reason for this?Thanks!(And sorry if this has been asked before, but my search terms didn't bring up this problem  )
Reply:Formula,Most likely you're removing your filler rod from the covering gas between dips.  If that is the case the rod is becoming contaminated as it cools in the atmosphere.  Try keeping your filler rod close, but not so close as to melt it before you get it to the puddle.Contaminated filler doesn't happen very often.  If it's been laying around for awhile, rub it down with a scotchbright pad and wipe with a clean rag with acetone.  That will remove any surface oxidation.Are you also brushing the backside of the material with a SS brush.  Sometimes impurities will be pulled from the backside of the bead.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:I'm with SundownIII.  The lost likely cause is failure to keep your filler under the shielding gas.  It may be that you have dirty hand/gloves as well.  Transfer of hydrocarbons from your hands can cause what you are seeing as well.
Reply:I'll vote for the removing the rod from the gas between dips scenario, especially when the rod gets short and you go to re-grip the rod, this is when it gets taken out of the gas flow.  If you see the end of your rod is black, don't dip it back into the puddle.  Stop and clean it off.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Sundown is dead on. I can elaborate on my more common mistake that causes this; I get the rod in, too close and it blobs on me a bit. I pull back, and then it oxidizes instantly. I drop it back into the puddle, and whamo! , I just created a mess. Clean dips and quick pull back from the puddle make a big difference. It's all a practice thing. Good luck!!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.
Reply:My guess is too cold. You are adding wire before the base metal is hot enough. It make a raised blob, that gets close to the Tungsten electrode. The electrode boils, the tip of the blob boils and you get a nasty looking mess. That is my bet. My aluminum wire comes out of the coverage gas all the time, never had a problem with that. When you did it on the plate with no wire, you had to be hot enough, or you would not have gotten a bead. That is why it comes out nice. When you weld try to get a puddle formed between the two pieces of base metal you would like to weld before you add wire. Raise the heat add wire and lift the torch slightly off the work and move forward a little. As soon as you are hot enough which will be almost instantly add a little bit of wire heat and lift the torch, move ahead. You may want to get a smaller filler wire. Are you using 1/8" filler wire? That will cause all kinds of havoc especially to a new welder. I use 1/16" filler almost all the time for everything. Except building up, and filling in. Aluminum is weird to weld, once you get the heat right you have to move rather quickly. To maintain a nice even bead. Slow down too much and you get a blob like weld that looks like a sand casting.        Sincerely,             William McCormick
Reply:Originally Posted by William McCormick JrMy aluminum wire comes out of the coverage gas all the time, never had a problem with that.
Reply:Of course you can take it out of the gas coverage, once its cooled down sufficiently.  If you take it out while its hot enough to oxidize you will get the exact reaction that the OP is describing. This isnt a mystery or an uncommon problem, it happens all the time to newbies and even to the more experienced guys occasionally.William, Im actually thinging your trying to make it harder on this guy than easier.  Lift the torch off the work?  Use smaller wire?  Those are two of the most conunter productive things ive ever heard for a beginner.  Larger diameter wire is much easier for novices to feed because it wont ball up as easily and allows for a slower motion.  And lifting the torch?   Once again, you know something that no one else does.Zap, it doesnt matter if you feed the filler from inside your ear.  As long as the wire has coverage when it cools, no problems at all.Have we all gone mad?
Reply:Originally Posted by zapsterMe either...I dont know WHY they think it has to stay in the gas..I can feed from BEHIND the torch and have no issues what so ever..Don't think so?I'll post pics tomorrow when I weld and take the filler and then twirl it like a drumstick and then dip over and over..again.....zap!
Reply:Did it by any chance look like the bead (if you could call it that) on the right in this pic? That happens to be a picture I took way back when I was learning, when I was trying to find someone who could explain why it was happening.  I was having the same problem as you.  Machine was a TA-185 (great machine, BTW), 3/32 red tungsten, .125 aluminum flat bar, 4043 filler.Bead on the left and the one on the right were done one after the other, with the only delay being regrinding the tungsten, as it stuck in the middle of the left bead.  The problem above was contaminants getting into the weld.  Bad argon wasn't the case, contaminated filler wasn't the case, nor was the base metal, or machine settings.  Best I found was that air was getting in, as the stickout was far too long for the cup size.  When the bead was nice, I was lucky, as I was really pushing the envelope on how far the argon can travel.  When the bead wasn't nice, it may have been a very minute difference in torch angle, or the filler interrupted the stream enough for air to get in, or something.  Anyway, shortening the stickout, and using the proper cup for the job seemed to fix the problem.  That is the problem with being self taught.  You have no one to tell you what you are doing right, and what you aren't.  Now, if you aren't getting near as bad a results as the one on the right, and are just getting a grainy bead, I'd tend to agree with what William mentioned, based on my own experiences.  I dug through my pictures, but couldn't find any that demonstrated that (thought I had some, as I remembered having problems with that as well).Last edited by bassboy1; 06-28-2010 at 03:47 AM.Who is John Galt?
Reply:Originally Posted by bassboy1Did it by any chance look like the bead (if you could call it that) on the right in this pic? That happens to be a picture I took way back when I was learning, when I was trying to find someone who could explain why it was happening.  I was having the same problem as you.  Machine was a TA-185 (great machine, BTW), 3/32 red tungsten, .125 aluminum flat bar, 4043 filler.Bead on the left and the one on the right were done one after the other, with the only delay being regrinding the tungsten, as it stuck in the middle of the left bead.  The problem above was contaminants getting into the weld.  Bad argon wasn't the case, contaminated filler wasn't the case, nor was the base metal, or machine settings.  Best I found was that air was getting in, as the stickout was far too long for the cup size.  When the bead was nice, I was lucky, as I was really pushing the envelope on how far the argon can travel.  When the bead wasn't nice, it may have been a very minute difference in torch angle, or the filler interrupted the stream enough for air to get in, or something.  Anyway, shortening the stickout, and using the proper cup for the job seemed to fix the problem.  That is the problem with being self taught.  You have no one to tell you what you are doing right, and what you aren't.  Now, if you aren't getting near as bad a results as the one on the right, and are just getting a grainy bead, I'd tend to agree with what William mentioned, based on my own experiences.  I dug through my pictures, but couldn't find any that demonstrated that (thought I had some, as I remembered having problems with that as well).
Reply:If you dip a tungsten, it will cause a problem. It is a good idea to get the aluminum off the tungsten. That can and will give you the casting look. Usually what happens though is you start to get the casting look, from too much heat in the part. Not enough power to just melt it and weld. When you dip your tungsten you get a strange ARC, that is not proper. So it takes you longer, you heat the base metal too much. That is why we use chilling and backing blocks, it actually keeps the heat pinpoint right at the weld. You can weld much faster and hotter then without chilling blocks. We were teaching a fellow who owned a machine shop to TIG weld one time. The other fellow, the welder did production aluminum furniture all day long. High end stuff. His welds without doubt looked much better then mine. Because of the speed at which he welded. Later as I did more and more aluminum, I could do the same thing. To be honest, I could pick up a torch that someone else just dunked, and start welding. And it will look nice. I just burn it out in a second or two. But if you have not done miles of TIG, it is most certainly best to clean your metal, your tungsten, and even your cup, if it is filled with aluminum. Or just get a new ceramic cup, that is what we do. Make sure you have enough gas 13-20 13 minimum and 20 at most, make sure you have a Teflon between your cup and torch. Make sure your gas lens is tightened into the torch. Make sure the cap has "O" rings and is not cracked. And you should be good to go. When you make two beads on a plate, next to one another. You just cannot weld the second at the same rate and heat as the first. You will have problems. The second one is preheated. You cannot just move along slowly like you did on the first bead with the same heat. Or you will cook the aluminum to much. You will dredge up all kinds of stuff. You will get blobs on the underside. An experienced welder loves the change in heat, because he can weld much faster. But I know if you are new it sucks. Because it is a change up. Someone mentioned large filler wire being a plus. I just cannot imagine that. Unless you are not yet able to feed filler wire. If that is the case, practice that for a couple hours. Just feed filler wire into a puddle on a plate. Until you are proficient at that. It is a little like eating with chop sticks you have to get used to it. With thinner wire you add more length of wire. But you tend not to freeze the puddle or build up the puddle. As far as lifting the torch go ahead. Believe me it is OK and recommended to do. As you lift the torch you increase the ARC length. This blends the puddle for you, because it heats the surface and expands the size of the ARC. It also tends to melt the new area you are moving to. I am not saying to lift it much, just enough, perhaps 1/8" to 1/4". When you melt the new area you are moving to, you are almost ready for filler wire. Aluminum welding is fast and furious.        Sincerely,             William McCormick
Reply:William,Sometimes I have to wonder if you don't post just to try to screw the newbie's up.  That's a pretty good trick there, just "burning off" aluminum contamination of the tungsten.Then there's the comment about smaller filler.  Brilliant.Lifting the torch about 1/4".  Stroke of genius.Turn off your computer.  Take off the tin foil hat.  Take your meds.  Nap until they take effect.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by SundownIIIWilliam,Sometimes I have to wonder if you don't post just to try to screw the newbie's up.  That's a pretty good trick there, just "burning off" aluminum contamination of the tungsten.Then there's the comment about smaller filler.  Brilliant.Lifting the torch about 1/4".  Stroke of genius.Turn off your computer.  Take off the tin foil hat.  Take your meds.  Nap until they take effect.
Reply:Originally Posted by sn0border88Hey now, he learned that from the master welder at northrop grumman where he and his dad welded on aircraft parts.  You know, back when people still got real education and not this propaganda mind control crap the govt. secretly feeds us now. When the jew supported the holocaust, and....
Reply:Originally Posted by SundownIIIWilliam,Sometimes I have to wonder if you don't post just to try to screw the newbie's up.  That's a pretty good trick there, just "burning off" aluminum contamination of the tungsten.Then there's the comment about smaller filler.  Brilliant.Lifting the torch about 1/4".  Stroke of genius.Turn off your computer.  Take off the tin foil hat.  Take your meds.  Nap until they take effect.
Reply:This is also done by lifting and moving. All my welding is done like that. Except for a few rare times, when I do not want a stack of dimes, but rather a perfect fusion seam look in a titanium alloy. And even that is rare. All my aluminum welds are done with 1/16" welding wire as well. I Never use 1/8" unless I am filling, or building.        Sincerely,             William McCormick
Reply:A lot of welders put their cup down on the work, which is also OK to do, nothing wrong with that either. I do it for many different types of welds. But when they or I go to move, we have to lift up the cup, or it creates a cut in the hot soft aluminum. You see these rough raw cuts in the aluminum if you drag your cup. If you have your ARC length at its maximum effective length already, then "no", you cannot lift because you will get a bad or fluctuating ARC. However most really good welders hold a short penetrating ARC, then they lift slightly to get the larger fanning ARC, that blends the bead into the work. This also washes contaminants back onto the puddle behind you. So you do not carry them down the weld. If you do not change your ARC length, and maintain a set distance, then a machine pulsing will create a somewhat similar but less powerful effect. To get similar results. That is why I don't use pulsing, I create my own effect.        Sincerely,             William McCormick
Reply:Increase the strength of the weld by 100 times.Now I KNOW you don't have a freaking clue what you're talking about.I figured you'd learned that "torch lift" technique from an alien you ran into while working for the government at Area 51.William.I'm not saying you don't know how to weld.  Obviously if you can keep food on the table, you're doing something right.  It's the "off the wall" comments that no one else can verify that cause the experienced guys here to question your sanity.BTW,I tig (heli-arc actually) my first aluminum fuel cell in 1966 for a raceboat we were running under sponsorship from OMC (Outboard Marine Corporation).  Since that time I've had the good fortune to be able to work with some of the best aluminum tig welders in the country (marine fabrication).  Also was lucky to have a next door neighbor who ran one of the largest steel fabrication shops on the east coast.  In fact, did considerable consulting with him.  Worked with some of the best SS tiggers (textile industry) thru this relationship.I may have been born at night, but not last night.  Some of your recommendations/comments have never seen the light of day, except in your mind.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Take your best weld done without a backing and chilling plate, and destroy it. It will break like glass. Unless you have giant blobs of aluminum in side the tank, or use backup gas.  But if you use a backing plate, with a slight chamfer on it. You can bend it past 45 degrees before it will crack. That is well over 100 times more strength.        Sincerely,             William McCormick
Reply:William,As an engineer, I can use an old phrase to describe comments like you just made.  "Partner, you're as full of chit as a Christmas turkey"."100x as strong".  Do you even understand what you're saying?  A weld only has to be as strong (or maybe slightly stronger) than the base metal you're dealing with.I've welded a fair amount of aluminum fuel cells for boats over the last many years.  Never had a "seam failure".  Still haven't figured out how I'd postion and remove those "chill bars" after I got the tank tacked up.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by SundownIIIWilliam,As an engineer, I can use an old phrase to describe comments like you just made.  "Partner, you're as full of chit as a Christmas turkey"."100x as strong".  Do you even understand what you're saying?  A weld only has to be as strong (or maybe slightly stronger) than the base metal you're dealing with.I've welded a fair amount of aluminum fuel cells for boats over the last many years.  Never had a "seam failure".  Still haven't figured out how I'd postion and remove those "chill bars" after I got the tank tacked up.
Reply:Hey there Chief it looks like the obvious, contaminated gas. Sometimes your local argon supplier does not purge the cylinders all the way and the welds do come out looking like cottage cheese. You knowc02/argon have the same valve assemby as argon. So if your welding and sometimes the tungsten burns back into the torch. It a pretty good indicator of gas contamination. Another good indicator of gas contamination or oxy inclusion is when you have to small of a cup like a #4 and still maintaining a 20 or 30 gas flow on the meter. To much gas coming out of the cup creates a venturi effect that produces a oxy molecule inclusion thus producing the cottage cheese effect.
Reply:Originally Posted by thermalfusioneng.Hey there Chief it looks like the obvious, contaminated gas. Sometimes your local argon supplier does not purge the cylinders all the way and the welds do come out looking like cottage cheese. You knowc02/argon have the same valve assemby as argon. So if your welding and sometimes the tungsten burns back into the torch. It a pretty good indicator of gas contamination. Another good indicator of gas contamination or oxy inclusion is when you have to small of a cup like a #4 and still maintaining a 20 or 30 gas flow on the meter. To much gas coming out of the cup creates a venturi effect that produces a oxy molecule inclusion thus producing the cottage cheese effect.
Reply:Okay, enough guys. We know where the rubber meets the road; we know there is more than one way to skin a cat. And, though some of us would not ever find ourselves doing a process one way or another, someone out there is doing it- right or wrong. You have made points and counter-points. As far as this thread goes, it has run it's course. Thank you for the examples of different welds, and the destructive bend work. I will say that if you are promoting a different style of welding, it might be wise and helpful to do a solid documenting job on the prep, the process, and the settings and equipment. In other words, do an informative post like Zap would. Then we can see what you are actually doing. It's far too easy to show a pic of a beautiful finished weld, and say " I did it like this...." It's too vague, and leaves you open for serious scrutiny. Work to avoid that, help your cause.Closed. Thanks for coming.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.