Contaminated AL filler rod?

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I recently bought a new tig, and I have been practicing with it.  On my aluminum welds, I keep getting contamination in the welds, but it seems that it is mainly when I asdd filler rod.  I can run a simple autogenous stringer and it comes out fairly clean (i didn't clean up the base metal. )......but when I run a stringer with filler, the weld is downright ugly.  Lots of black spot all over it.  I have tried this on a few different pieces of aluminum, and everytime I add rod I get the same result!  I don;t have any pics to show you as I am at work right now.  I'll try to get some pics later to show you what I am talkign about.  Of course, I have tried other rods from the pack, and the result is the same also.  Could it be that I bought a pack of contamiated rod?  BTW, the rod is 3/32" 4043 filler.  I am welding with a 3/32" Thoriated tungsten.  The Welder is a Lincoln Invertec V205T AC/DC.
Reply:Its more likely that in this situation you are taking you filler wire out of the gas coverage and its getting oxidized there.  When you dip again your throwing that crap into the puddle.Try it again paying close attention to where the end of your wire is, and how far from the puddle you are.Have we all gone mad?
Reply:Hello BurningMetal, snOborder88 had a very valid point about removing the rod from the protection of the shielding gas while you are dabbing in and out of the puddle. Additionally, you should pay careful attention to the condition of the rod itself, I believe you mentioned that this was some used rod that you had picked up. That being the case, you should look over it very carefully to see whether it possibly has some form of chemical contamination on it's surface, such as: oils, solvents, paints, or other such contaminants. Another possibility could be excessive oxidation from improper storage over extended periods of time, this could be simple oxidation or possibly oxidation that included salts if you are anywhere near the ocean or other saltwater bodies. If you notice any contamination from solvents or such, using isopropryl alcohol and a clean rag will likely take care of cleaning the rod sufficiently to take care of contamination. If oxidations/salts could be an issue, then using an aluminum oxide based abrasive followed by an isopropryl alcohol wipe with a clean cloth would likely take care of cleaning sufficiently to prevent puddle contamination. Just a few more thoughts for you consideration. Best regards, Allanaevald
Reply:Like mentioned above it's possible your pulling your filler rod out too fast causing the filler to be contaminated, it's also possible that if your gas coverage is insufficient, simply moving the filler rod into the arc area may cause enough turbulence to mix in some atmosphere and contaminate your weld. Pay attention to how your holding your torch, keep it pointing close to 90 degrees to your weld area, check that your using enough gas (but not too much) 15 cfh is a good baseline to start at. Use more if your using a larger cup. ,Lastly pay attention to your arc length, do not go beyond 2x the dia of your electrode.  I've had the same issues that you describe and for me its almost always a sheilding gas issue.
Reply:Another possibility is a contaminated wire brush if you used one.  I had a sudden problem with increased porosity TIG welding with 4043 filler rod on 6061 aluminum.  From a process of elimination, I discovered it was caused by my new so-called stainless steel brush.  I replaced the brush with a brand name (Anchor) one and all was well again.  (or at least as well as it was before).  A few months before the brush problem, I had some a somewhat similar problem because my tungsten became contaminated.  A small amount of material had become caked on the sides of the tungsten near the tip.  I discarded about 3/4" of the tungsten to get rid of the contaminated section and everything was good again.Electronics Engineer (embedded controls)Miller 200DX w/ Coolmate 3Thermal Dynamics 82 plasma cutterGrizzly G0678 8x30 millPM1440BV 14x40 latheHF 6x12 surface grinder
Reply:the gas coverage/removing the filler from the "gas cone" might be the issue.  I'll have to pay more attention to it.  The cup on my torch is pretty small.....smaller than I am used to using with other machines. The filler rod I am using is brand new......it looks good, but that is why I was thinking I got a "bad" batch of rod.
Reply:Originally Posted by BurningMetal The filler rod I am using is brand new......it looks good, but that is why I was thinking I got a "bad" batch of rod.
Reply:Dave,I bought the rod at PRaxair.  It's nice that Indian River O2 is local, but their prices are nuts!  tungsten and rod are about double what they can be purchased for if you look around.  I like to support local businesses, but not if I am getting screwed!  Their gas prices seem decent though.
Reply:Originally Posted by BurningMetalDave,I bought the rod at PRaxair.  It's nice that Indian River O2 is local, but their prices are nuts!  tungsten and rod are about double what they can be purchased for if you look around.  I like to support local businesses, but not if I am getting screwed!  Their gas prices seem decent though.
Reply:interesting......
Reply:I doubt it has anything to do with your rod. If your regulator is set to more than 20cfh, and you are breeze free, then I doubt it is your gas coverage. It could be the gas itself. I just recently had this exact problem and I thought it was moisture in the gas. I changed bottles and still the problem persisted. So I thought it was contamination from my wire wheel. I muscled my way through that second bottle in hopes of finding the problem. Finished off that small bottle and instead of going back to the first, I hooked up a third bottle I had just gotten and YAHTZEE!!!!!!   It was like my machine was given brand new legs and all was right with the world again.Bill LambertArgon WeldingABQ NMSic gorgiamus allos subjectatos nunc
Reply:my argon fill is proably 6-8 months old and wasn't used much prior to the last month.  I had no issues with some steel Tigging I did though....so I am not sure it is the gas.It is probably something to due with me!!  operator error more than likely; I may tray a larger torch nozzle, too,
Reply:I had my doubts too. I thought it was me. Then I thought it was the aluminum. Then I thought it was a carbon steel wire wheel I bought for my grinder. I jumped though so many hoops. Even went and bought some etching acid to clean the surface of the aluminum. I was avoiding the gas issue because I was short on funds. Only reason I even had another bottle to use is because my uncle works for a local w/s and brought me a 300cf bottle. He gets so much for free each month and brings most of it to me. He used to just stack them in his yard. Once you have 100 bottles, your neighbors don't like you so much. So now I am the beneficiary of his perk. He, in turn, gets all the free welding he needs.Bill LambertArgon WeldingABQ NMSic gorgiamus allos subjectatos nunc
Reply:Originally Posted by BurningMetalmy argon fill is proably 6-8 months old and wasn't used much prior to the last month.  I had no issues with some steel Tigging I did though....so I am not sure it is the gas.It is probably something to due with me!!  operator error more than likely; I may tray a larger torch nozzle, too,
Reply:okay.........I am a dumbass!!!!  I went back and playe with my Invertec. It turns out that there were 2 problems.1) the aluminum was alot dirtier than it looked.  I took out the SS wire brush and brushed it up.  I was getting all sorts of little black junk when brushing the AL.  The AL cleaned up well.2) I needed to use more "cleaning action."  I had the EN% set to around 75%.  I had to get it down around 50% on this material.All seems well now......I just need to work on my technique...ALOT!!!  Here are a couple of before and after pics.  after looking at the before pic, I now see that there was crud in the autogenous (non-filler) stringer, too. In the after pic, you can still see some crud in the stringers, but it is ALOT better than the before pic. Attached Images
Reply:update............got a new bigger bottle odf argon today.......upped from a 40cf to a 125cf bottle.  ..........and now the welds are fantastic!I think ArgonWelding was right; there may have been contamination in my old argon tank.I have noticed that my beads are cleaner, brighter, and overall better looking.  Also, I have been able to change my % of EN (A/C Balance) for more penetration....which allows me to lower the overall amps and keep a sharper point on my tungsten!  I'll post pics tomorrow.
Reply:I lost all real interest when I read "I didn't clean the base metal".Kinda like saying I'm tired of the dirty britches but I don't wipe after using the toilet.BTW:  Could you post up some photos of those "fantastic welds".  Thanks.Last edited by SundownIII; 02-17-2010 at 12:16 AM.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:The first row looks like a row of stacked banana slices.Wow loads of dirt floating around, if you add filler to that then it becomes a real mess.I also find lingering at the outter edge of the argon shield contaminates the filler, keep it in close.
Reply:Originally Posted by SundownIIII lost all real interest when I read "I didn't clean the base metal".Kinda like saying I'm tired of the dirty britches but I don't wipe after using the toilet.BTW:  Could you post up some photos of those "fantastic welds".  Thanks.
Reply:here you go........it is funny when you look at a close up photo, you really see all the imperfections.  oh well. again, this was on 2 unprepared (no wire brush or acetone) pieces of aluminum.  The weld is a butt joint where the 2 pieces of AL extrusion are designed to come together.
Reply:Originally Posted by BurningMetalhere you go........it is funny when you look at a close up photo, you really see all the imperfections.  oh well. again, this was on 2 unprepared (no wire brush or acetone) pieces of aluminum.  The weld is a butt joint where the 2 pieces of AL extrusion are designed to come together.
Reply:Thanks Rojo.  It's fun seeing yourself progress in making decent welds.  Also, thanks again for your advice on getting the Lincoln Invertec V205T AC/DC.  It's a great machine!
Reply:Originally Posted by BurningMetalThanks Rojo.  It's fun seeing yourself progress in making decent welds.  Also, thanks again for your advice on getting the Lincoln Invertec V205T AC/DC.  It's a great machine!
Reply:Originally Posted by BurningMetalhere you go........it is funny when you look at a close up photo, you really see all the imperfections.  oh well. again, this was on 2 unprepared (no wire brush or acetone) pieces of aluminum.  The weld is a butt joint where the 2 pieces of AL extrusion are designed to come together.
Reply:Originally Posted by RojodiabloWhat settings are you running?? Pre-flow, Post-flow, ramp up time, downslope, freq. and cleaning?? I read the part about setting back the cleaning; that can do a real good job for you. The other settings are also interesting in how they change your weld profile and shape, as well as size and depth of penetration.