My first Al. tig welds

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Gathered up a little aluminum yesterday and tried to stick it together. I've heard that it can be really difficult, so I'm pretty stoked with the results, I seem to be better at aluminum than steel.Ran some practice beads because I didn't know what aluminum even looked like when it was hot and ready for welding. They are numbered in the order I welded them, all were dome at 185 amps, 20% balance and 60Hz, 3/32 red tungsten and a #6 gas lens.After that I tried a seam. All the welding paramiters are writen on the material, if you can't read it let me know and I'll type them up. 1/16" material, 1/16" filler, 1/16" red tungsten and a #4 gas lensThe only problem I had besides a slight bit of inconscistency was that the back-side didn't seem to be fusing quite right. The weld seemed to be plenty strong because I couldn't get it to break apart, but I know this isn't what it should look like.Next atempt I tried switching the wave balance to 15% wave balance, seemed to help, but it still didn't work quite right. I also think I screwed up the filler dip slightly, should have dipped closer to the arc I think. I also ended up with too much heat in the work-peice and started getting drop-through at the end of the bead, I was able to fill it all in without getting holes of pourostity though.See, it looks like I got better penetration but still have issues on the back-side. Any ideas on the solution? More heat? More filler? More beer before I start welding? All welds are with my new TA 185, it's so smooth and easy to set-up it's rediculous. I think I'm going to scrap my plan to mig togther a quick steel cart for it and maybe go for super-bling aluminum.Last edited by maxyedor; 01-07-2008 at 01:58 AM.
Reply:You say 15% wave balance, you mean turned all the way to the left?  It looks like you had it up quite a bit by the cleaning shown away from the edge of the bead.  I have a TA-185, I have used it A LOT with no problems.  I find 25% + wave is about as low as I can go and get enough cleaning.Just keep practicing......  Nice for the first timeDavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:i would say you are still running a little cold, kick up the heat and the cleaning. i suspect you are waiting on the pudle, it should be almost instant. you want to be right on the edge of burn threw and use the filler to cool the pool.your off to a good start though.  i decided to make a cart out of aluminum for mine also, seemed only right.  after a wile of doing little cut off's i was getting realy bored with practice  and decided to move on to the cart. doing out of position work taught me a lot about the weld pool. as for the TA-185, i also think its a great lil TIG unit.Last edited by David R; 01-07-2008 at 05:52 PM.Reason: Fix pics summer is here, plant a tree for mother earth. if you dont have time or space, sponcer some one else to plant one for you.feel free to shoot me a PM or e-mail me at [email][email protected] i got lots of time.
Reply:if i got this right you had 70A peak, 20A background, pulsed @ 1Hz with 100Hz AC freq and 85% EN (or 15% EP)if you'd done that without pulse you would probably have got fusion at the root. the heat was there (at peak) but not concentrated enough because of the pulse. you could up the peak a bit to give a series of overlapping spot welds or up the background so it cools -rather than freezes- the puddle. i'd just turn it off and use filler/foot to maintain a consistant puddleAl's a bit different to steel regarding root fusion. the oxide layer interferes with fusion (the arc can only clean the area it's contacting) and the high thermal conductivity means you will have a wider root than if doing a full pen weld on stainless/mild. while you can achieve root fusion with little to no root reinforcement on ss/mild there will always be reinforcement with Alwith no root gap you need to watch the puddle begin to sink (that's the indication that you've melted through) and add enough filler to cool the puddle and give the cap. it's a fine line between burning through and not achieving full pen but just needs a little practice.i did a little sample here of what to look out for... http://www.weldingweb.com/vbb/showthread.php?t=16894
Reply:Welcome back Fun4now.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:maxyedor,please explain your pulse settings.  What is the 20 A HS, and the 70 A MAX?Is it 185 amps peak amps, 70 background amps, 0.1 pulses per second, and 20% peak time?Anyway, for one thing the pulse spacing is just a little too far apart as you show the back side pulses are not overlapping enough, so slow down the travel or speed up the pulse frequency.Last edited by pulser; 01-07-2008 at 07:40 PM.
Reply:Sorry, 20 amp hot start (I believe that's Thermal's name for background amps), 70 amps peak on the thinner stuff, 70 amp hot start and 185 amp peak on the first picture. No pulse it was all foot-pedal, the .1 is pre-flow time, I just stepped through the menu and wrote down the settings on the material, probably completely irrelivent, but more info is always better. 20% is the wave balance, so as I understand it that meens 20% EP and 80% EN, I've found that when I go much over 35% the EP puts too much heat in the tungsten and causes it to ball up and the arc gets sloppy.Went to the metal shop today and picked up a bunch more scrap aluminum so I'll give it another go as soon as I have some more time to screw around with it. I have a feeling I'm not using enough heat, I was thinking about it today and I don't think I was mashing the pedal enough, so I was probably welding with, at the time I thought I was good to go because of the bead showing on the back side, I just wasn't sure about why the 2 bubbles weren't connecting.
Reply:You have the balance thing right. Hot start is the second light on the screen and is not background current.  The pulse button is on the top of the panel, when you push it, what ever was welding current is now back ground current.You shouldn't be able to ball the 3/32 tungsten until you get over 50% and are up there in amps.  125 amps @ 65% + will ball a 3/32.  I can't do it at 50% even on 185 amps.On the digital display there are lights that read in amps, Hz, and % watch these little indicators it will help you set it up.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I never did get that particular joint project "successfully completed" on the project list last semester. We even had steel clamping jigs for butt and corner joints to use. I do know that the "entire surface" needs to be scrubbed with a stainless brush or chemically cleaned or both. The face, the edge and the root.Edit:- This is an example I kept, it is however not mine! The instructor did this right in front of me and my sizeable pile of failures.Not the prettiest on the surface, the stops and starts could be cleaner, but the focus of attention was placed on gaining complete penetration.Now for the root!You'll notice that the root reenforcement never really wets together, there is always a witness line where the two peices were butted together.How to acheive this much is beyond me at this point.Last edited by tanglediver; 01-08-2008 at 02:21 PM.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Those are nice pictures.  Wish we could see yours.  Just keep at it, the more you do, the better you get.  DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I don't know anything about all this pulse stuff or any of that happyhullabalooo...But it looks real good to me..Little more heat and slow down on the dips and you've got it!...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:Played with Al. a little more today, didn't have a chance to shoot any pictures, but I found that no matter how much heat I put in and how much filler I dip in there I can't get that root to seal, it got to the point that I have a good 1/8"+ tall bead on the backside, but still had the visible line of the seem on the top of the weld. When I used the same amperage settings but keep my foot on the gas just a little longer I get a better bead apearence (dipping the filler closer to the arc helped too) and have a smooth concistent bead on the backside. I think I'm close to figuring out aluminum well enough to build something.I also messed with some stainless with good results and then played with copper a little bit, that stuff is crazy to weld! .120" copper plate took almost more heat than my TA185 could deliver, but once it got hot I almost couldn't back the throttle off far enough.
Reply:It's been awhile since I've TIG welded Al, but I believe the line you see on the back side has alot to do with the oxide on the sheet and it may be superfical, not actually extending into the weld metal, depending on how well you cleaned the joint prior to welding.Proper cleaning of the joint, just prior to welding may help mininize the oxide line on the weld drop-thu.  First remove oils with acetone, then remove oxide with SS wire brush.  All surfaces of the joint must be cleaned and oxide removed, not just the top, also the butting edges and the back side.  After tack welding the joint front and back can be SS brushed again.Yep, copper needs to be hammered with a ton of heat real fast, and you can't dottle around, otherwise the heat spreads away so fast you're just preheating the whole damn workpiece and once you do get going the whole thing is overheated.
Reply:Try setting a bit more spacing gap between the 2 pieces. That should help eliminate the unfused seam on the backside. Puddle control gets a bit more tricky with increasing gap, but you can get the hang of it.
Reply:I just bought a TA185 . I wish it was more informative on the sequence on the panel. I pretty much figured it all out by now but it was a lil confusing at first.The back ground amperage is the % of the main amperage of the welder.If you set the back ground amperage of 50% @ 100 amps, you'll have 50 amps during the background side of the pulse. Lowering the back ground amp % reduces the heat input.This affects the puddle fluidity.On carbon steel/stainless use 20/30% of peak amperage.On aluminum set it to 35/50%To get your rhythm on aluminum practicing, try 1 pulse per sec.When I attempted my first beer can, my settings were.Pre flow:.1hot start: 0base/back ground current: 5Apeak current: 25A with pedal.pulse width:80%Pulses per sec:175wave balance: 65%AC frequency: 125HZpost flow:4Sharp 2% thoriated red tungsten.acetone cleaned aluminum8CFH straight argon no wind. Have fun!P.S I did have wind blowing under my carport when I was trying my first attempt at this thin aluminum can. Attached ImagesLast edited by cmartman46; 08-24-2009 at 02:43 AM.THE OLDER I GET! THE  SMARTER MY DAD WAS!Thermal Arc 185 inverter Tig welderABITIG 26  tig torchLotus foot pedalLincoln 225 stick welderClark 185SG Mig spoolgunwelderVictor torch/regulatorsHF36" shear,bender,roller.
Reply:Another thing I did to help ground the can while welding: I connected an aligator clip to the beer tab to cable ground. Too much CFH flow tends to move the can while welding.I think welding beer cans are good practice, intricately speaking.THE OLDER I GET! THE  SMARTER MY DAD WAS!Thermal Arc 185 inverter Tig welderABITIG 26  tig torchLotus foot pedalLincoln 225 stick welderClark 185SG Mig spoolgunwelderVictor torch/regulatorsHF36" shear,bender,roller.
Reply:to help get fusion on the back side of the weld i was taught to file a small 45 on the bottom edges.