1st aluminum welds...advise?

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Okay, first aluminum welds.  Plate is 1/4" 6061.Trailblazer 302 EFIHF-251D-1Water cooled torch3/32 balled green tungsten#8 cup (a little small as it turns out...at least according to Millers weld calculator)25cfh pure argon1/8 filler metal (also a little small...was burning this stuff up fast)190 ampfrequency intensity at 70%Here are the welds...not great I know, but I figure it's a go at it for my first Al welds.I know I cratered the ends on some of those.  You can also see where I was having problems feeding fast enough with the thinner filler metal as I'd wobble the torch a bit trying to get it to dip to the puddle fast enough without getting my fingers too close and roasting them.Metal was cleaned with a fresh SS brush both where the welds were laid down and where the ground clamp was connected.  I didn't do any clean up before taking this picture.I am happy with the water cooled torch though...heck of a difference from the air cooled (I wouldn't be able to hold the thing pushing over 150amps for more than 3-4 minutes with the air cooled torch).On the second weld down from the top I got a crack between one of the puddles and the next right where the puddle lip joined the previous puddle...any ideas why this happened?Thanks in advance guys, I appreciate the help and guidance.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:Need more amps for 1/4" aluminum. 1/8" filler is fine. #8 cup is fine. 25 CFH is a little high but if the puddle acts fine its ok. You need 1/8" pure tungsten or 3/32" alloyed tungsten, the 3/32" pure is going to melt back too much and shake around.The welds don't look bad for your first time, just need more amperage.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Sorry, not 1/8 filler, 1/16, I mis-typed.  I did notice the electrode jumping around a bit, I'll pick up some 1/8 green back tungsten tomorrow along with collets and collet bodies for it.  I'll also pick up some 3/32 and 1/8 filler.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:Get a gas lens setup.  You can turn gas down to 10-15 CFH and still get good coverage.  Save some dough. Get Blue 2% lanthanated tungsten, arguably the best all around and cheaper than the new special blends.  No need to change tungsten when switching from AC to DC.  If you're gonna have a steady diet of 1/4", I'd go with 1/8" tungsten, even in alloy.  1/16 filler is gonna disappear into 1/4" material.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:I've had best luck with Gold Tungsten on Aluminum. I normally only use a #3 cup for penetration passes at 15cfh and a #4 cup for cover passes at 15cfh with a little helium mixed in.
Reply:Originally Posted by jesseowen27I've had best luck with Gold Tungsten on Aluminum. I normally only use a #3 cup for penetration passes at 15cfh and a #4 cup for cover passes at 15cfh with a little helium mixed in.
Reply:12 SFH for your gas..3/32" Red tung..SHARP!!!!!Yes..use the 1/16" filler..I dunno why everyone needs such LARGE filler....I don't even have any 1/8" and don't plan on getting any.200 Amps and take your time....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:More practice.  I tried 3/32 2% thoriated with a sharp tip at 12cfh and 200amp...however, either the machine didn't like it or a setting was wrong for it somewhere.  It sputtered like crazy, partially melted the tip and really didn't make a nice bead (the arc was erratic and kind of hopped around as opposed to stabilizing).  So I switched to the 2% Lanthanated (blue) balled tip at 200amp, 15cfh pure argon, #7 ceramic cup and that seemed to work quite well.  Using 3/32 filler and working the pedal to control the heat input (if I just max the pedal, move and dip without dropping amps it creates a nice smooth weld with no "dimes" I don't think that's a bad thing, but since everyone kind of expects dimes, that's what I've been practicing to).Here's the pics of the latest run.  There are some areas in there where I was trying different things relating to movement, dipping, and pedal work, so you'll see some noticeable variation in the beads.  Still looking for advice Another question is relating to SS TIG:  I've never had much luck getting that nice colored weld with SS, it always seems to come out gray instead of the classic "rainbow" coloring.  I've tried different tungsten, going slower with lower amps, going faster with higher amps, gas lens, cleaning with acetone, wire brush, grinding, higher/lower cfh.  Always turns out the same...always gray...it's a smooth clean weld inside, I've cut them apart, ground them in layers, etc... and I've never seen any porosity...just always gray instead of shiny.  Is there any suggestion here...maybe something I'm missing?Thanks again guys,--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:Post some pictures of your stainless and we can help.First picture is 16G stainless. Second picture is mild steel, but nice and shiny like it should be.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Here's an idea of what I'm getting (these were just done to show what's happening, not much effort put into them, but they have the same surface look as any weld I end up with on SS or carbon steel).Here's the shots on SS (prepped by grinding, cleaned with acetone, brushed with a fresh SS brush).  3/32 2% lanthanated, #7 ceramic cup, 20cfh argon, 308L filler, running foot pedal.  Material is 304 1x1 .120 wall square tube.Here's some carbon, prepped by grinding with a clean CBN wheel, wiped with acetone.  Same settings as above.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:These should be some better examples.   Switched to a #8 gas lens running at 15cfh, around 180 amp but running the pedal and trying different speeds/filler feeding rates, 3/32 2% lanthanated, 1/16 308L filler.Plate is a 3/16" T-304 ground and cleaned with Acetone.Color looks a bit better with the gas lens, but still pretty gray...Any ideas?--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:Originally Posted by SquirmyPug3/16" cup welding aluminum? Your electrode is only a little smaller diameter than the cup
Reply:I would up your gas to 20 or slightly higher.
Reply:Okay, I think I've figured it out...Settings are as follows:1/4 304 SS plate ground and cleaned3/32 2% lanthanated220 amps but didn't get near that running the pedal18cfm argon1/16 308L fillerabout 7 IPM as far as I can guessWhat I did differently (maybe this will help someone else with the same problem):I upped the gas a bit from 15 to 18, but that didn't make a difference, so I started playing around with pulsing the pedal (made it worse).  Finally, I moved my electrode as close as possible to the weld (within about 1/16 to 1/32 of the puddle) and that worked.Here's the weld done with the electrode running really close above the puddle...much more like what I'd expect:What do you guys think?  Do I have it here and just need more practice from here on out?thanks again for all the help.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:Interesting thing I noticed today.  Apparently when welding aluminum a gas lens isn't a good thing?  I couldn't figure out why the aluminum welding went down hill today and then realized I had changed to the gas lens.  Took it off and everything was back to good.Also, I figure that almost no color but shiny and silver is also okay for stainless steel?  Since I've moved the electrode in much closer to the weld that's what I've been getting.  Figured I'd ask if that was normal and good.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:No color and shiny on stainless is perfect. That means you were getting very good gas coverage. We only use gas lenses on Aluminum while using pure helium for our X-ray welds. Otherwise just stick wit the standard collet body. Yes try to stay as close to the weld with your tungsten without dipping in. Also, the amount of tungsten stickout will play a part in how your weld looks, but the more stickout, the more gas coverage you will need.