Small aluminum tig welds? how?

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trying to master tig ally.  but seem to be getting massive fillets.  ie welding sheet material but getting welds with huge leg length etc.what is the realistic expectation of how small a fillet tig weld you can do on 1/8" (3mm) ally.
Reply:Picts? Settings?I'd say most of the students at the tech school usually end up with roughly 1/4" legs on the fillets using 1/8" plate. A few can get them down to 3/16" if they are really good.Key to this is heat control. You need to hit it fast to get the puddle going and fly. The slower you go, the bigger the bead will get. Running a pointed tungsten will help you keep your arc small and aid you in this. Large pure tungstens will make this tough. My guess if you have large fillets would be you are going too slow and possibly running your amps too low. Without picts or settings however, I'm guessing blind..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:Ditto........pics  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Yep managed to smash out a nice fillet or two just the other day.  I think my problem is that I am traveling too slow.This time instead I just said stuff it and was dabbing in the filler rod at about 2-3 times every second.  The result, perfect fillet weld very tight and small.  Compared to what I was doing that is all it was and it has made such a big difference.  Should have taken some pics but the job has gone out the door and we are off for xmas.    But just for anyone else I was on 90Amps, freq was on max, sharp tungsten, tip of tungsten was say 2-3mm off puddle and just dab dab dab the filler really fast.  It is really easy as you just sit the filler rod in the corner of the joint and simply slide it along the joint into and and out of the puddle.
Reply:Don't forget to pulse between filler dips to keep the heat down.
Reply:90 amps is too cold for 1/8th thus DSW guessed right on both accounts of slow and not enough amps.    set to 125-150 for Aluminum if you are running straight Argon.Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:if your using a square wave turn your wave control all the way to the PEN side and depending on what amps your running try keeping your tungsten groomed to almost a point using whatever you decide to use transformers work with Cereated (Orange)  but most guys with tranny welders have pure  (Green )  Holding a tight clearance to your work piece helps also..........With an Inverter welder run more Hertz   to narrow up the weld....Smaller filler also helps  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:This is a real double-edged sword here. Once I explain, DSW and BC will agree: When you work toward making a small puddle on aluminum, you get 2 possible negative side effects: 1. Lousy penetration. You might run a weld where the bead is small, and the puddle never gets down into the material. While the bead holds decently, there is no real strength, and you will see the weld fail once put into use.2. If you run a small bead, there is a good chance that the weld itself will be hot enough, but with sheet material, the heat will be sucked away so badly, so quickly that the HAZ next to the weld puddle will crack almost immediately upon cooling. This phenomenon is much worse when you turn the frequency up really high to try and get that tiny bead with good penetration. Example: I was welding a fuel cell out of .100 5052. The outer corner welds were done with a freq. of 150, and the beads were pretty nice, and yeah, fairly small. So I stuck with that setting for the seams on the tank. My tack welds seemed to go just fine. But.... once I started running stringers to tie the sheets together, I had multiple cracks along the HAZ. It really bugged me, and I checked and re-checked everything. I took some scrap sheet, and prepped it the same way, and welded it. And it cracked. So, I investgated. The weld penetration was about 90% but the puddle width was almost nothing down in the seam. And this is on material only.100 thick. I could flex and crack any weld done this way, with any filler-4043, or 5356. I recognized the lack of lateral fusion in the puddle, and so I first tried more amps. This made a bigger hump on top, and yes, penetration went thru the material for 100%, but the cracking on the edges persisted.Next step, I checked all settings. I felt the one change was the frequency. So I dialed it back to 90hz. and laid down a bead. And it held perfectly. So I did another, and beat it silly. GTG! I had to go back, and found that there was not 1 crack in the weld, but 2 cracks; on either side of my filler give or take. The sheet cooled so fast, and the bead was so narrow that the filler material was not fluid down into the weld far enough to keep the embrittlement issue to an acceptable level. But with the lower frequency, there was adequate fusion and blending of the filler with the base metal, and the wider heat zone allowed for better thermal reaction when cooling. The bad side was taking out nearly 4 feet of 1/8" filler in a crack, and then having to weld it all back together with a 1/8" or more open root on .100 material. Blech!!!!!!!!!!!!!!!!!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:Originally Posted by B_C...guys with tranny welders...
Reply:Be careful with travel speed while TIGing aluminum.  It's easy to get a really good bead appearance but have very little penetration if you travel too fast.  In my experience it is usually best to learn to control the heat input with the peddle rather than with travel speed.  That way you always have a good view of the interaction between the leading edge of the puddle and the root and can dip your rod at just the right time when the keyhole begins to colapse.  If you are feeding your rod in very quickly it gets difficult to tell if you are really getting good penetration or not because you don't get a good view of the joint.Last edited by puddlepusher2012; 01-04-2013 at 04:34 PM.
Reply:Transformer Square Wave Welders........  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Want a small bead?Use .035 or so filler....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:Pretty much depends on where you want that small narrow bead......Very thin material requires a "Touch"  Very thick material requires the right machine and prep.....Pangea and I went through the DC- with pure Helium a couple years ago and made believers out of some guys that never heard of that procedure before........This is 1.250 thick flanges welded to .500 thick tube with NO PRE-HEATusing DC- and Grade 5 Helium no way you could get the beads that narrow with AC and pre-heat.......the material has to be really clean which this tube wasn't and I got some dirt to surface on the outside weldbut very good pen and strong with DC-  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:This is what it should look like if everything is right.....After the soot is brushed off........small good pen welds in tight spaces...  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Whats the aluminum fire hydrant riser tube thingy for?Welding/Fab Pics: www.UtahWeld.com
Reply:I think I saw a post by pangea on a Hobart forum. What filler rod did you use? Just plain tig rod, or flux coated rod? Was high frequency needed?
Reply:Joseph if you are thinking about your mobile alum thread, you might want to price out lab grade helium you need to do DC tig on alum. I'd suggest you talk to your doc for heart meds first if you haven't looked at the price of ultra pure helium before... There's reasons why DC alum tig is not generally used, and cost is one of them..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:I already imagined that helium was high priced, most likely why there's not much heliarc welding anymore. I welded dc with straight argon and used a Hobart 1/8 4043 stick welding rod and rigged it like that and it actually turned out good, but when doing the same with regular 4043 tig rod results were very poor.
Reply:Originally Posted by B_CThis is 1.250 thick flanges welded to .500 thick tube with NO PRE-HEATusing DC- and Grade 5 Helium no way you could get the beads that narrow with AC and pre-heat.......the material has to be really clean which this tube wasn't and I got some dirt to surface on the outside weld but very good pen and strong with DC-
Reply:Originally Posted by MikeGyverew... not the best place to save typing a few letters.
Reply:The part was for PG& E not sure what it did......When you weld aluminum with DC-you pretty much set up the same as for steel of comparable size and thickness with the exception of the Grade 5 Helium.......I used a 5/32 red tungsten with a gas lens #7 cup I think  and 20 CFH  gas flow 5656 3/32 filler  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Originally Posted by joseph_zlnskI already imagined that helium was high priced, most likely why there's not much heliarc welding anymore. I welded dc with straight argon and used a Hobart 1/8 4043 stick welding rod and rigged it like that and it actually turned out good, but when doing the same with regular 4043 tig rod results were very poor.
Reply:And yes with the price of Lab grade Helium you don't see me taking too many DC- aluminum jobs in......I have one bottle left and it was 345.00 for a 288 size Lab GradeLast edited by B_C; 01-09-2013 at 03:54 PM.  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Originally Posted by B_C it was 345.00 for a 288 size Lab Grade
Reply:I called airgas it was 75 dollars for a 20lb bottle size of grade 5 helium. Not to bad of a price, for mabey having a bottle hangine around when needed for a specific job.The only reason I ever use it is HIGH DOLLAR DC-  semi-conductor jobs and their almost non-existent anymore.....Another reason I'm glad I bought the Dynasty, it doesn't need the Helium as much as my Transformer machine did.......Much cheaper  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock