Arc blow on TIG AC while welding aluminum

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Hello,I was trying to welding a T joint earlier on 5052 .125 aluminum.  It took me around 5 minutes to strike an arc.  I checked the leads, tightened anything I thought might need it, adjusted the ground to various spots.  When I finally got the arc to strike it was a bit sporadic.  I was rather shocked at first as to how much wander there was.  Then the arc just started floating upward like magic.  I was really surprised, I couldn't do much with filler and even while keeping the peddle hammered down I wasn't able to form any sort of puddle.I thought that was a bit weird but it reminded me of some of my earlier days of welding and I thought I was doing something stupid I had been doing previously.  Obviously, as the title stated, I some how pondered if magnetism could some how effect my weld.  It seemed so far fetched but there it was in my mind.  I googled "magnetism effect tig" and the first link brought me to realize my suspicions to be true.  I read on this forum about arc wander and it seems there may be a different version of it that what I just read or at least a different understanding of it.  What I believe is that the table underneath the aluminum is, slightly, magnetic.  I have been using an old saw table as a welding table.  The magnetism passes through the aluminum, of course, and really seems to repel my arc.Does this all sound possible and real?  I am still a little shocked by all this and it makes me wonder why anyone would have a ferrous welding table.  I am rather disappointed to learn this though,  I spent a great amount of time long ago and not so long ago trying to figure out why I could strike an arc or why I was unable to keep my arc from wandering so insanely.  I thought it was the argon, the torch, the machine, zombies playing with my mind.  Only in the past week or less have I started to find real success in welding, want to know why?  I think this is hilarious.  I recently purchased some very thick aluminum angle, I found the best way to setup is to have the angle hanging off of the table a bit!  That was it!  I have to believe this all to be true but it all sounds so radically insane and impossible.  I only imagined recently through some form of magic, as though someone else put that thought there (william?) and forced me to imagine magnetism shoving my arc around like two magnets that don't want to touch no matter the cost.In my personal life, this is a shocking realization and development.  I am in the market for a new welding table, I am thinking aluminum mesh of some kind, : D.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands.  If you want to know why, click here.Buy American or bye America.
Reply:AC welding current is not usually affected by magnetic arc blow. Aluminum is not usually a metalthat can become magnatized. I would check your for proper grounding and also check to see if HF isworking properly
Reply:You've got other problems not related to magnetism.No reason it should take so long to get a puddle.Either your machine is not providing continuous HF or your technique is all wrong.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:Is the HI FREQ. switch set to the bottom or still on start?..(Top Setting)Put it on the bottom.."Continuis"...zap!Last edited by zapster; 08-20-2010 at 10:32 AM.I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Hah, this is what I mean by 'a different understanding' of arc blow.  I'd take a video of it if I could.  I have an older transformer TIG, if there was a problem involving the HF, the arc would either fail or start and stop, that wasn't the case at all.  Alternating has both positive and negative currents within, I see no reason why it wouldn't be affected by magnetism.  I kind of want to try and place a magnet around a flat piece of aluminum as I weld it to see if it moves it around.  I believe the iron welding table underneath has some magnetic properties and has been the cause of this, as I said in the post.As far as I know, aluminum cannot be magnetized.  But magnetism can pass through aluminum.  The arc was being pushed away, I was holding it, at best, a 45 degree angle but usually to start something at that angle I hold the torch straight down.  The arc was going up for a while, like it was trying to climb and invisible ladder.  I just want to be clear, what I think is occurring isn't magnetism building up, I think magnetism that is within the welding table is affecting the arc in my weld.  I am definitely going to perform an experiment to be sure I understand these findings.  I am sure a few of you can do the same.  All I am going to do is strike an arc on a flat piece of aluminum, obviously using AC with HF on continuous.  And then I am going to place a magnet directly underneath where the weld is occuring.  If the arc suddenly begins to do what I described earlier, than my findings will be verified.http://website.lineone.net/~diverse/layer2/zeropr.htm This is the article that I read.  For me, the reality and what I observed is plain and simple, when I welded on the table, the arc was extremely difficult to start and the arc was very erratic and there was pretty severe blowing occurring.  When I welded off the table, the arc was perfectly stable, easy to start and there was zero blowing.  I feel like I've gone from playing a game in super hard mode into easy mode.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands.  If you want to know why, click here.Buy American or bye America.
Reply:A few years back I was doing aluminum with an old Linde machine. Every so often, I had to slide a little sand paper between the HF contacts to keep them working properly.UA Local 598
Reply:You think I should mess with the HF contacts?  I've adjusted them to various gaps to test different settings, I have it at .010 right now which is what I think the manual calls for.  It also says in the manual that you aren't supposed to clean off those contacts, at least for my welder.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands.  If you want to know why, click here.Buy American or bye America.
Reply:Just as I suspected, I took a fairly powerful magnet and brought it towards an arc.  The closer I got to the arc, the more sporadic the arc became and just as interesting, the more resistance I felt in my arm that was holding the magnet.  I had no trouble starting the arc and the arc looked very uniform and clean, I started a puddle or two and then moved the magnet closer, as I did the arc 'blew'.This is highly interesting to myself and I am sure it is interesting to many others.  I am certain that -very- many people here use corner magnets to hold pieces of metal in a corner joint.  I imagine that even the places where a magnet has been held to will retain at least a little magnetism and thus, distort your TIG weld fairly substantially.  If I can figure out how to keep a welding lens in front of my camera I will upload a video of this occurrence for your observation.Of course, many of you folks could easily reproduce these results on your own.  As the article that I linked to stated, TIG welding is the most easily effected kind of welding my forces of magnetism.  I'd either switch everything to clamps and aluminum or get yourself a de-magnetizer.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands.  If you want to know why, click here.Buy American or bye America.
Reply:http://yfrog.com/mrarcblowzThis is a video I made this morning to demonstrate the effects of magnetism on TIG welding which is often referred to as arc blow.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands.  If you want to know why, click here.Buy American or bye America.
Reply:Try putting a filter in front of your camera.  It doesn't have to be a full shade 10, but something to cut down on the glare.  If you have an extra auto darkening helmet, that would work VERY well too.  Unfortunately, I couldn't see what you were describing in the video.As for arc blow.  The magnetic field is directional, and will cause opposing effects when the polarity reverses.  So on DC, you will see the arc wander, but it shouldn't be "pushed" off at an angle on AC like you can get with DC.  The arc WILL still be affected by the magnetic field on AC, but in more subtle ways.
Reply:Why is it that I never have had any of these "Problems"??...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Zap,Maybe because you get the "silent beam" right now.If it's taking this dude 5 minutes to strike an arc, he's got issues that have nothing to do with the table.I'd suggest he and William McCormick handle the solution by PM.  Seems that those two are the only ones operating on that "wavelength".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 SundownIIIZap,Maybe because you get the "silent beam" right now.".
Reply:Originally Posted by SundownIIIZap,Maybe because you get the "silent beam" right now.If it's taking this dude 5 minutes to strike an arc, he's got issues that have nothing to do with the table.I'd suggest he and William McCormick handle the solution by PM.  Seems that those two are the only ones operating on that "wavelength".
Reply:This may have been asked already but....did you try moving the ground closer to the work?I will say, that you can "electromagnetize" aluminum. When I weld on pontoons, it is not unusual to have the back end off the rod stick to the boat when the current is being applied. When you let off then the rod "unsticks"If your table was once a tablesaw and the motor and all the electric stuff that it once had, managed to magnetize the top and frame or whatever then it is tough luck IMO.I would think it would have little shavings and crap stuck to it then and also you should be able to take something like a screwdriver and hold it real close and it will jump to it and stick if it is magnetic.It doesn't sound far fetched to me....just something few people on this forum would experience because not many folks are using table saw tops for welding tables. I can see why you would want to tho.I would either find a way to de-magnetize it or get rid of it.Rest assured tho, this is not a normal problem with a steel table or welding aluminum with AC current. I had the same machine as you before I replaced it with my 700 Dynasty and they don't do funky stuff like that when they are set up properly.I would be curious to know your cup size, tungsten size and shape, and gas settings as well as stickout length etc. as one would think this could be fine tuned to work better. I would not use the table as a ground on aluminum myself and very little normally anyways.Grounding to the part helps many starting problems.Miller Dynasty 700Miller 350P with Aluma-pro push-pullMiller 280 Dynasty with expansion card Dynasty 200 DXMigMax 215 Enuff power and hand tools to create one of anything..... but mass produce nothing!!!
Reply:Originally Posted by FusionKingThis may have been asked already but....did you try moving the ground closer to the work?I will say, that you can "electromagnetize" aluminum. When I weld on pontoons, it is not unusual to have the back end off the rod stick to the boat when the current is being applied. When you let off then the rod "unsticks"If your table was once a tablesaw and the motor and all the electric stuff that it once had, managed to magnetize the top and frame or whatever then it is tough luck IMO.I would think it would have little shavings and crap stuck to it then and also you should be able to take something like a screwdriver and hold it real close and it will jump to it and stick if it is magnetic.It doesn't sound far fetched to me....just something few people on this forum would experience because not many folks are using table saw tops for welding tables. I can see why you would want to tho.I would either find a way to de-magnetize it or get rid of it.Rest assured tho, this is not a normal problem with a steel table or welding aluminum with AC current. I had the same machine as you before I replaced it with my 700 Dynasty and they don't do funky stuff like that when they are set up properly.I would be curious to know your cup size, tungsten size and shape, and gas settings as well as stickout length etc. as one would think this could be fine tuned to work better. I would not use the table as a ground on aluminum myself and very little normally anyways.Grounding to the part helps many starting problems.
Reply:You are making a mountain out of a molehill..Get your ground clamp as close as you can get then see what happens..I have had my share of problems with this and that over the years but never to the extent that you are "Experiencing"..Most are solved within 5 mins...I think you need to start from the beginning all over again..Nobody has these problems like you seem to have..Not putting you down but something is just NOT right......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:If AC (alternating current) changes polarity (+or -) based on frequency (Hertz), how can it be affected by magnetism or become "polarized"? In the past, when magnetic arc blow could not be over come with DC- or DC+ welding, ormethods to demagnetise the material we would switch to AC welding processes(GTAW or SMAW). Therefore, I am not convinced that you are experiencing magnetic arc blow. I would check the HF and the grounding for problems.
Reply:Concerning building yourself a welding table, you can possibly save some money by using angle iron for perimeter and legs and firebrick for the top, about the cheapest way I can think of.
Reply:Originally Posted by pistolnoonConcerning building yourself a welding table, you can possibly save some money by using angle iron for perimeter and legs and firebrick for the top, about the cheapest way I can think of.
Reply:If your not just trying to jerk everyone around, me and pro-x-60 might consider a trip 30 minutes East to get you on the right track. We would have to be invited of course.
Reply:pinjas - I can see the magnet is making some kind of an affect on the AC arc from your video.  And this is clearly contrary to some information we've read that says that only a DC arc is affected by magnetism.  Your video is really pretty clear.  I have not seen this illustration before, and have indeed wondered about it.This may explain why changing the AC frequency, as well as pulsing parameters on AC can make a difference towards stiffening the arc, making it more directional and constricting it from wandering as far off to the sides.  I would hypothesize based on the evidence shown in your video, that with higher AC frequencies, there is less time for the arc to "wander" sideways from magnetism.  When the polarity switches, it may very well "reset" the position of the arc, and keep it overall closer to the tip of the electrode.  Similarly, when pulsing current drops, it may also similarly reset the position and shape of the arc, closer to the electrode tip.So, *thanks* for shedding some light on a possible explanation for those phenomena with your video demonstration.Last edited by jakeru; 08-26-2010 at 02:12 PM.
Reply:Hadn't looked at the video before,it is pretty easy to see the arc changing a lot as the magnet gets close.I don't know where the widely held idea that a magnetic field would only affect  DC weld current came from, must be just another one of those old myths that needs busting.
Reply:The video may not be perfect but I think the results are indeed pretty clear.  As I've noted several times, this experiment is extremely easy for a large number of people here to reproduce.  Just grab a magnet, get some aluminum and put your high frequency on constant.  I am glad some were able to appreciate the video I made.  I have been thinking of getting a darker lens filter for my helmet and my camera, I have the lenses made to 8 and 9, while using the number 9 on any weld longer than a foot I see a dark spot in my vision like you'd see if someone flashed a camera in your face too closely.  Maybe the darker lens would enable a better view of the arc.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands.  If you want to know why, click here.Buy American or bye America.
Reply:Just watched the video and I am a little confused with what you are trying to prove.Are you saying the reason that you had had trouble welding using your new welding table was because of magnetism? Or are you saying that a magnetic field can affect an arc? If you are saying that magnetism affected your welding with HF, AC  current on aluminumI would say that it is unlikely. However, if you are saying that a strong magnetic field can have an effect on an arc, well then that is just a fact. Your video is simply a magic trick. You introduce a magnetic field then remove it then introduce it again. The arc does  not have enough time to stabilize and therefore looks eratic.Originally Posted by davinwheelJust watched the video and I am a little confused with what you are trying to prove.Are you saying the reason that you had had trouble welding using your new welding table was because of magnetism? Or are you saying that a magnetic field can affect an arc? If you are saying that magnetism affected your welding with HF, AC  current on aluminumI would say that it is unlikely. However, if you are saying that a strong magnetic field can have an effect on an arc, well then that is just a fact. Your video is simply a magic trick. You introduce a magnetic field then remove it then introduce it again. The arc does  not have enough time to stabilize and therefore looks eratic.
Reply:So the real question is......how are you gonna DE-magnetize your table???This thread is getting rather boring unless you are gonna work on a solution.I say move forward and not debate the subject. Less drama!!Miller Dynasty 700Miller 350P with Aluma-pro push-pullMiller 280 Dynasty with expansion card Dynasty 200 DXMigMax 215 Enuff power and hand tools to create one of anything..... but mass produce nothing!!!
Reply:Originally Posted by FusionKingSo the real question is......how are you gonna DE-magnetize your table???This thread is getting rather boring unless you are gonna work on a solution.I say move forward and not debate the subject. Less drama!!
Reply:I am still trying to figure out what is going on here..So far....Nothing....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:get a 1400F temp stick and a really big rosebud.  heat your table to 1400, let cool and problem solved.
Reply:actually,  your table is probably cast,  so the temp would be higher.  its a fairly impracticle soltion for a table anyways. when I was in the navy we wrapped the ship I was on in some really heavy gauge cable and ran a bunch of current though it to neutralize the magnetic signiture.  That was quite an operation.  But it was 3 weeks in Hawaii, so who am I to complain.