How to weld corner joint of aluminum?

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I have some .063 aluminum and I'm trying to weld an outside corner joint. Basically just built a box to practice. I have a lot of questions.I have tried on 63amps (I have tried 10cfh and 20cfh, short stickout and long stick out) on a #8 gas lens, 2% red and 1/16th ER4043 filler rod.I tried to tack them together and no go. Didn't seem like it wanted to fuse them together.What is a good way to hold these two pieces together? Got a cheap fast rig I can rig up? Should they touch or overlap each other? What is a good torch angle? The filler rod seemed to not melt, but start to melt and hang down like a loose booger. I can't get a good puddle or a bead going at all.I sprayed them with acetone, wiped down with a green scotch brite pad and used acetone again. All I'm getting no matter what my settings is boogers. Or if I get the 2 pieces to start to fuse they don't move towards each other.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Fit up is really critical with that thin stuff. And the proper way to do the joint is in a v with the low edges touching, not over lapped. If there is any gaps of daylight with the thin stuff it will start key holing on you. After I tack it I like to look for any slight gaps and lighty tap it with a hammer to make sure it's very tight.And if your puddle is rejecting your filler you might need to clean the oxides off your filler as well.
Reply:Just tried again and used a 2% cereiated and same thing. The damn tungsten got stuck in the collect and snapped off on the end. Ugh. At least it's not as brittle as green. That **** broke when I looked at it. GasThis was at 70amps. StickoutFail picturesAs you can see here I tried to clean the metal with the torch after I used acetone. Didn't make much of a difference.This is the exact metal I ordered. 6061 T6 and pvc on one side. I thought maybe it didn't weld right because of the pvc, but even after a wire brush no difference. I flipped it to the other side and still no difference.Any help is appreciated. Originally Posted by SR20steveFit up is really critical with that thin stuff. And the proper way to do the joint is in a v with the low edges touching, not over lapped. If there is any gaps of daylight with the thin stuff it will start key holing on you. After I tack it I like to look for any slight gaps and lighty tap it with a hammer to make sure it's very tight.And if your puddle is rejecting your filler you might need to clean the oxides off your filler as well.
Reply:Gotta be a gas problem, are you sure that the torch is flowing? You might hear the solenoid actuate but the reg might be bad, that's happened to me.
Reply:Your electrode should not be turning blue.  Check for gas.My name's not Jim....
Reply:You need to learn to walk before trying to run---IOW--justpractice on flat stock first. From the look of most of thosedroppings, it appears you do have gas coverage.On thin, gently play the torch-looking for the very first signs of surfacewetting--looking wet and shiny-then melt little ball off filler in the wet area, then add little more.If that ball or the puddle you're making, starts to blend in, nice and flatto the surface---that means it's melting thru to the other side and that areais over heated. This is a game that's all about reading the heat and thenknowing how to 'throw' that heat.On thin, you cannot just slam the heat to it and expect good results.(High energy pulsing can be done on thin--but this requires being ableto read and throw the heat-first.)Blackbird
Reply:Your gas coverage looks fine, but it's not going to hurt if you bump it up a bit but basically if your weld is shiny then gas isn't your issue. Your issue is heat. More specifically - controlling it. Set your AC balance to 50% for starters. Set your amperage to 50 amps (may need to increase a bit, but start with this first).Arc up on the corner. Don't add any filler. Move the arc around in a tight circle between both bits of metal - you should be starting to see both edges of the metal start to get shiny. Keep going until a small puddle forms on BOTH sides of the gap, this might take 2-3 seconds for the cathodic cleaning action to do its job. Only when you have a small puddle on BOTH sides do you start with the filler. After you've practised this a bit you can then play with your amperage to speed things up.If the aluminium is anodized then you need to grind this off.If you really can't control the heat, the next step is to add a backing plate behind the joint (either thick aluminium or copper). With practice though you shouldn't need this.Cheers- MickLast edited by weldermick; 08-25-2011 at 05:02 AM.
Reply:I would practice on the flat metal until i had it down pat before worrying about corners, especially outside corners.Dynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:Your electrode is way too far out, & Try a #4 cone.  I do .063 at around 100 amps (not full pedal) With a 3/32" electrode.Keep the tungsten close, 1/8" arc gap max.PVC as in "a plastic" coating?)  Try some naked Alum, anything that isn't metal doesn't weld to metal.Buy American, or don't whine when you end up on the bread line.
Reply:All along when you have been trying to weld alum, you been told that you need to learn heat control. Now you are begining to see why it's so important. What I see is you are either too hot, or too cold here. You lack the fine control over the variables that are needed to do thin alum. You can't simply mash the pedal and go for it. There's no secret magic trick to doing this. It's all about heat control.You really need to step back and learn the basics if you want to learn this the easiest way. Start with steel. When you can do good welds in all positions with 1/8" steel, then switch to thinner steel and do it all over again. Then switch to 1/8" alum and do it all over a 3rd time, before trying to do alum this thin. 1/8" steel will help you get the basics down, such as adding filler, consistancy of movement, torch angle and so on. Thin steel will quickly show you where you are lacking in these areas and refine your skills. 1/8" alum will allow you to reapply all these basics to alum and learn it's quirks. By this time, if you have been doing it right and taking your time and really learning, this won't be all that hard.There's no "quick" way to do this. You've had your machine how long and started tig when? My guess is that it's less than 3 months. I know you mostly skipped steel and dived right into alum from your previous posts.  I might see you at the point you could be doing this, if you were learning tig  full time in school, but even then you'd have to be the rare exception to the rule. That would be with someone to stand there and watch exactly what you were doing and suggest pointers on what you are doing wrong.There's simply no substitute for hood time. Expect to have a couple hundred hours under the hood before you can suceed with this. My guess is you don't even have dozens of hours logged yet..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:Hey Gamble,I believe Doug(DSW) has provided your solution.....you need serious practice with steel first, then some copper, & then advance to alumium. Each metal will fine tune your skills till it will come naturally. TIME!.....lots of time. Seems the newbies/inexperienced feel superb results can be obtained with a few hours of making puddles. Not gonna happen... especially with the thin(>> vs ))) is that more torch angle or more filler angle?Bed time for now, more practice tomorrow after work.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Originally Posted by GambleFlap wheel to grind it off? I used a wire brush, but I'm guessing that wasn't good enough. Last thread I had someone said not to use a flap wheel
Reply:Originally Posted by B_Cread your original post and skimmed through the replies......Looked at the pics and I guess from the holes you need to figure how to tack this type joint?   Well first off your filler is too small. Us 3/32 and more amps say 125 or so......The gas lens isn't necessary  and I like pure tungsten unless your on an inverter machine (didn't say)get into position and get the heat on quick and concentrate on the filler rod with a "Painting " motion your going to burn through if you try to heat the parent metal firstunless your real good with aluminum (which your not after looking at your pics)  so practice with scraps as mentioned......Thin aluminum isn't the easiest to weld so don't be discouraged.....
Reply:Setting it at 125 doesn't mean running at 125It means hitting it and letting off, he is tacking It's much faster with that power than let's say 75 amps or lower......you want to heat the Tack and get out, not a large area  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Whatever works for ya..... I   Would blow  a hole in my beer cans if I heated the can Before running a bead......The larger filler Wire is the key  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Originally Posted by David HillmanSlightly off-topic question...   Is the blue tungsten a problem, or a symptom?  I mean, let's say he blued it with the grinder as you described.  Would that effect the welds made later?  If so, what should you do in that case, cut off the blue tungsten and re-grind (more carefully)?   Thanks.
Reply:Gamble, I'm a newbie too. FWIW, a few things have helped me.  You have an inverter with a set frequency and ac balance.  So your getting a very tight focused arc.  Iirc, your machine is preset at 100 Hz.  You won't tend to ball up your red tungsten that easily.  At least for me, a pure tungsten at 70% balance made a nice little ball that widened the arc a bit and helped me get the thin medal joined.  I think green tungsten isn't recommended on your machine, but I cant see how it would hurt.  it will probably form a nice little ball.  Just check to see if it would actually hurt your inverter in anyway.Also, preheating with a propane torch makes more of a difference than I'd ever believe.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:AWS certified welding inspectorAWS certified welder
Reply:Originally Posted by B_CRegardless of how thin the aluminum you won't burn through if you concentrate  the heat on the filler......just takes practice
Reply:Was showing that you can apply as much filler as you want if you keep the heat off the thin material........I think the machine was set at 125 amps and I just used what it required.......yeah thats the bottoms...I filled the V..........  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock