Need help on alum fillet w/ TIG

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I’m trying to learn to TIG aluminum and need help.I started out just laying beads on a flat plate.  I brushed the plate pretty good w/ an alum-dedicated sst brush then played around with freq, balance,  pulse, amps til I got the beads I liked.  Took about an hour.   I think they look great. (see first pic) So I’m thinking “what’s the big deal…this is easy.”Then I tried a fillet weld and everything went to hell.For the fillet welds…Base material:  3/32” 6061 T6 x 1/8” diamond plate (spec?)Filler rod: 3/32” 4043Machine: Dynasty 200 DX w/ foot pedal,  160 amp, 60% balance, 175 – 200 hzElectrode: 3/32” 2% thoriated,  ball tip, #8 gas lens, ¼” stickoutShield gas: 20 cfh argonPrep:  Clean w/ soap and hot water, dry, brush both sides, edges, everything w/ alum-only sst brush til all oxide gone and the brush starts to really drag.  Wipe with clean paper towel and acetone.  Also, wiped filler rod (just in case) w/ new scotchbrite then wipe w/ acetone.Torch held at 45 deg to both plates and about 15 deg off normal.  Rod held at 5 – 10 deg  from joint parallel.  All just like the literature says.  I start the arc and throttle up til the pool(s) start to form.  Here’s where it gets dicey.  I get pools forming on each plate about 1/8” from the intersection of the plates.  I’m not getting a pool right at the intersection where I need it.  When I really pour the heat to it to get the intersection to melt the pools fall thru.  I tried higher freq and more cleaning on the balance but it doesn’t seem to work.Pics 2 thru 4 are my best examples.  Some actually look like welds but there’s no consistency.  The only way I could get these was to REALLY mash the pedal till the pools looked like they were about to fall then feed some filler quickly to bridge the two pools then throttle back a little (not too much or the pool solidifies) then start moving fast and jabbing the filler rod in and out quick.  If I was slow on the filler motion the rod tip melted into a big ball and fell on the work.  If I went too fast I would “out run” the puddle.I guess it’s a matter of heat control, travel speed and filler rod motion (in other words – practice).If any of you guys have any suggestions on settings or technique please let me know. Attached ImagesMiller 211 w/ spool gunMiller Dynasty 200DXLongevity 60i IGBT plasmaO/A w/ crappy chinese torch/gaugesSouth Bend 10K latheGrizzly 4029 10x54 millGrizzly 7x12 hor bandsawangle grnders, bench grnder, bench belt sndr7.5 hp 80gal cmprsor
Reply:Try 75-80% balance, move torch slower, advancing without a weld is a waste of time, and when your rod balls up and hangs give it a flick to get rid of the drip and then continue welding.My name's not Jim....
Reply:With aluminum you have to add filler to get the puddle to start or else you'll get what your getting.  Also turn your frequency back down to 60 and just try that since your learning and it will give you the effect of what it would be to weld with a transformer.  Then after a while turn it up 20 and give it a try and so forth.  There is no point in having all those adjustment if you can't tell the difference between settings.
Reply:Fillets need more heat than flat plate. Crank up the amps , you can always back off the pedalG
Reply:try turning amps up or going slower also make sure you have correct stickCigweld Transmig 265seBoc 140amp StickBoss 200amp AC/DC TIGLincoln Electric Invertec V260-S
Reply:Why are you balling a thoriated tip?  Put a taper on it, and just knock the very tip off.  If that doesn't eliminate the problem, decrease your arc length.  You should get both pieces to flow together before you even add material, at most a small dab of filler if the fit isn't perfect or the edges start to melt back.
Reply:Put a point on the tungsten, it'll ball on it's own from the alternating current, but nice and small. that will help focus the arc more, also keep the arc short as already mentioned. Start out hot. if its taking too long to get the puddles to snap together, your heating up the entire work piece. With alum. fillets you need to go Hot and Fast. You will have to back off gradually as you move along, using the foot pedal."SOUTHPAW" A wise person learns from another persons mistakes;A smart person learns from their own mistakes;But, a stupid person.............never learns.
Reply:I would try pure tungsten instead of 2% thoriated. let er ball upI was using 2% at work and then switched to pure tungsten ( green band ) and made ( to me ) a very big ( good ) difference!
Reply:Thanks all.Supe and Papabear - Re the tung tip, I'm actually starting with a tapered electrode (w/ a blunt tip) which forms a ball after a few seconds.I'll turn up the amps a little more for starting and see if I can get the two pools to flow together.Joscerb55 - I'll try the pure stuff when I get over to my LWS.Things apparently happen much faster with alum (and especially the fillet joint)  than CS/SS...heat on FAST, throttle back FAST, move the torch FASTer than I'm used to.  I think I just need to "get up to speed".Miller 211 w/ spool gunMiller Dynasty 200DXLongevity 60i IGBT plasmaO/A w/ crappy chinese torch/gaugesSouth Bend 10K latheGrizzly 4029 10x54 millGrizzly 7x12 hor bandsawangle grnders, bench grnder, bench belt sndr7.5 hp 80gal cmprsor
Reply:Don't use pure with an inverter or square wave machine. Any thing BUT. I personally like 1.5% Lan. for alum., but first learn with what you have before worrying about tungsten type.
Reply:Good grief...I am glad someone caught that one.  Pure is NOT used on inverters. In my limited experience with Dynasty machines, they do run very well with 1.5% Lanthanated on aluminum. Even Ceriated might be a better choice than Thoriated.QamuIs Heg qaq law' lorvIs yInqaq puS
Reply:Papabear....thanks.Where in rural NY are you.  I spent some time in Herkimer and Olean.  Built a power plant at a paper mill in Little Falls.  Visited Schenectady and Saratoga Springs.  Beautiful country and friendly folks.Miller 211 w/ spool gunMiller Dynasty 200DXLongevity 60i IGBT plasmaO/A w/ crappy chinese torch/gaugesSouth Bend 10K latheGrizzly 4029 10x54 millGrizzly 7x12 hor bandsawangle grnders, bench grnder, bench belt sndr7.5 hp 80gal cmprsor
Reply:Originally Posted by BTDPapabear....thanks.Where in rural NY are you.  I spent some time in Herkimer and Olean.  Built a power plant at a paper mill in Little Falls.  Visited Schenectady and Saratoga Springs.  Beautiful country and friendly folks.
Reply:I think you'll like ceriated or "rare earth" tungsten over 2% thoriated for aluminum work, but the 2% thor will work well enough.  defiantely don't use "pure" on an inverter.  The advantage of using an inverter is that you can use a much % of Electrode negative (less cleaning action) for you aluminum welds.  As such, if you have clean aluminum, set your %EN to 75-85%.  it'll keep a nice point on your tunsgten and you can really focus the arc into the joint!  also, you may want to back the frequency down to between 100-125 HZ.  aluminum fillets are definately tricky, but it seems that getting a focused arc into the groove is key.  you may need to get your tungsten in tighter to the joint too.
Reply:Ok...it's a little better tonight.  Bought an 8' long piece of 1/8" x I-1/2" alum from Home Depot ($18).  Up'd the balance from 60% to 80% and the amps from 160 to 170.  Tried to get the tung a little closer and really mash the pedal on start-up.Never could get the two puddles to join up unless I dabbed a little filler in the grove.  Once the puddles came together, I backed off the pedal (sometimes too much) and on several instances was able to walk the puddle across the workpiece with the torch and an occasional dab of filler.  When it worked, the puddle flowed fast across the joint and the filler made up the alum left behind.  Looks like the trick is hand-hand-foot coordination (read torch-rod-heat).  I think I just need lots of practice...and cheaper aluminum.  I also need a better work surface.  I'm clamping the piece in a vise and trying to balance my hand on the vise jaw..not very steady and the vise gets hot...so does the torch.Hey, at least it's starting to look like a welded joint. Attached ImagesMiller 211 w/ spool gunMiller Dynasty 200DXLongevity 60i IGBT plasmaO/A w/ crappy chinese torch/gaugesSouth Bend 10K latheGrizzly 4029 10x54 millGrizzly 7x12 hor bandsawangle grnders, bench grnder, bench belt sndr7.5 hp 80gal cmprsor
Reply:Skip Depot for material. You will want to go somewhere that sells metal. Depot charges premium prices for stock. I forget what the small place near me sells alum that size for, but I'd bet it's less than 1/2 Depot's price..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:Big improvement over the first pics. Like you said, a better work surface (so you have something to steady your torch arm) will help a lot, and tons of practice.By the way....Is this where you worked in Little Falls, NY?Just figured, since I was passing through and had my camera........... Attached Images"SOUTHPAW" A wise person learns from another persons mistakes;A smart person learns from their own mistakes;But, a stupid person.............never learns.
Reply:I like to set my stickout so that I can stick the cup right into the corner and still not dip the tung.  I think it's like an 1/8" stickout with a #6 or #7 cup.  Resting the cup against the material helps keep me steady.My name's not Jim....
Reply:Originally Posted by papabearBig improvement over the first pics. Like you said, a better work surface (so you have something to steady your torch arm) will help a lot, and tons of practice.By the way....Is this where you worked in Little Falls, NY?Just figured, since I was passing through and had my camera...........
Reply:Originally Posted by BoostinjdmI like to set my stickout so that I can stick the cup right into the corner and still not dip the tung.  I think it's like an 1/8" stickout with a #6 or #7 cup.  Resting the cup against the material helps keep me steady.
Reply:Originally Posted by BTDPbear...If I remember correctly (1985), there were two Burroughs plants in Little Falls.  The one I built the plant at was at the end of Mill Road.   The one in the photo is on Mills but closer to the main highway (I think).
Reply:Tried a few changes and things are working out even better tonight.I added some pulse to see what that would do.  Also increased the frequency a little.  Don't know if the new settings made any difference or if I'm just a little further up the learning curve.  I also repositioned the bench vise so my wrist now rests on the table...much cooler now...no more "ouch that's hot...need to hurry up and get to the end"One more thing I notice is that I'm using up filler rods at a great rate.  Not like CS or SS.I also need to learn how to feed more rod thru my glove with my fingers.  Right now I start with about 9 inches of filler and have to stop when I need more.  This gets me about 3 or 4 inches of weld bead.Also, I'm paying more attention to how I dab the filler rod.  Sometimes I tried to slide the rod along the joint and into the puddle and pull back.  Now I'm lifting the rod slightly away from the puddle then dropping the rod back in at the front of the puddle...the motion is sort of a 45 deg angle.  When I'm accurate, the pool runs nicely along the joint.  When I miss the target, the rod melts ahead of the puddle and things get ugly. But I haven't touched the tung...Yeah!Now I've run out of aluminum.Current specs....Base material: 1/8" Home Depot aluminum (???)Filler rod: 3/32” 4043Machine: Dynasty 200 DX w/ foot pedal, 170 amp, 80% balance, 225 hzPulse: 30 pps, 70% max amp time, 70 amps backgroundElectrode: 3/32” 2% thoriated, taper tip w/ flat, #8 gas lens, ¼” stickoutShield gas: 20 cfh argonPrep: wipe workpiece w/ acetone and brush w/ alum-only sst brush.Torch held at 45 deg to both plates and about 15 deg off normal. Rod held at 5 – 10 deg from joint parallel. Attached ImagesMiller 211 w/ spool gunMiller Dynasty 200DXLongevity 60i IGBT plasmaO/A w/ crappy chinese torch/gaugesSouth Bend 10K latheGrizzly 4029 10x54 millGrizzly 7x12 hor bandsawangle grnders, bench grnder, bench belt sndr7.5 hp 80gal cmprsor
Reply:that's great progress.  aluminum fillets are, by far, the most troublesome joints for me.  I am getting better though.  each time get a little better.
Reply:Looks real good. Monstrous improvement in a short amount of time.
Reply:i only did it when i was in school and i just couldn't get the hang of the verticals. that last pic looks way better than I ever did, really awesome; just the open ends are all thats left.