Scruffy looking TIG welds on Aluminum

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Hi,First I'm new here, so please be gentle.I've recently got myself a Kemppi TIG ac/dc machine and set about learning to tig weld aluminum and stainless. SS kind of OK, seems as I work on small items, I get them too hot. A work in progress there. Aluminum is another subject entirely. The welds look awful. I'm running pure argon, 250Hz AC, balance EN at 62.5%, current controlled by a foot pedal, but kinda 130 amps.  Tungsten is zirconium doped, 3/32", no. 7 gas lens.  Aluminium samples in these photos are T6061, Filler rod is 4043, 3/32".  Workpiece is new Aluminum, everything cleaned with dedicated wire brush, filler rods cleaned. Argon running at 20 cfm.Butt joints are generally OK ish, overlap kind of OK ish and fillet joints are just an embarrassment. The arc puddle looks clean while welding (don't think it's oxide in the puddle), but once it cools it has little lumps. The first image is a butt joint, ground to a V, material 1/8.  The next two are fillet joints.I would appreciate any advice for a newbie.Regards,Gavin. Attached ImagesKemppi MLS 2300 AC/DC, plus all the usual "stuff"
Reply:Aluminum welds will often come out kind of rough and grainy looking.  Sort of like your first picture.  Using enough amps to puddle quickly and keeping the puddle moving will improve the appearance.  Also with clean new material you should be using more EN, 70 or75%.  I think your low EN and slow speed is what is frosting your other two welds pictured.
Reply:Ok, thanks.  I can try that in the morning.Kemppi MLS 2300 AC/DC, plus all the usual "stuff"
Reply:More amps. for 1/8" use at least 150 amps, pound the pedal to the floor to get the puddle to form NOW, and move fast as soon as the puddle forms backing down on your amps as the piece heats up. I go even hooter, 180-200 amps and I get a puddle almost instantly when I hit the pedal. However your reactions have to be faster backing off the pedal to keep from blowing holes in things.The little lumps or pimples you see in your bead comes from the silicon in the 4043 filler. If you overheat the material by taking too long to get the puddle started like what happens when your amps are too low, you get that look. It sounds backwards, but more amps faster, puts less heat into the plate and you get a cooler weld overall..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 have the same welding machine. Apart from what the others said, one word of advice:Ditch the zirconiated tungsten for some 2% lanthanated (or 2% ceriated, 1.5% lanthanated, 2% thoriated). Anything but zirconiated, report back how it goes.
Reply:Try adding filler more consistently your kinda all over
Reply:Originally Posted by taz00I have the same welding machine. Apart from what the others said, one word of advice:Ditch the zirconiated tungsten for some 2% lanthanated (or 2% ceriated, 1.5% lanthanated, 2% thoriated). Anything but zirconiated, report back how it goes.
Reply:That's why I switched to the 1.5% gold band tungsten. The zerconiated did have a clean arc tho.
Reply:I tried a few more fillets today, got the current up sooner and higher.  Couldn't find any 3/32 lanthanated tungstens, but did find some E3.  They seem to work well.  (Lanthium/zirconium/yttrium from memory). The fillets look better, but that slight crustiness is still present. A work in progress.Kemppi MLS 2300 AC/DC, plus all the usual "stuff"
Reply:You can eliminate the silicon islands by switching to 5356 filler rods. A benefit over 4043 is 5356 is not dependent on base metal dilution for it's strength as 4043 is. It is strong right off. Another thing with 4043 is to remember is speed is your friend as when the heated the silicon migrates to the surface, so you can outrun that effect. Pushing an extra amount of filler to plump the bead will also chill the weld and prevent the silicon migration. Good on ya for getting the E3. I bought a lot amount at auction and hand it out to my crew. Best thing is when dipped they seem to re-glaze the tip pretty good. Overall though your technique is pretty good.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.