Al Tig Porosity

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i cant seem to get this figured out.  the welds seems to have a bunch of voids in it.  the surface of the weld looks pretty good.  stacked dimes, but it dosnt finish like ive seen pros do it.  ive seen pros tig and there welds come out almost shiny with just a little white at the base of the filler material.  im getting a duller finish over the whole weld.  i have been using a stainless brush only for AL over the joint and hitting it till its shiny shiny shiny.....then a wipe with acetone.  the AL has been inside in a dry enviroment.  the filler is 4043 3/32 the al is 1/8" im not sure of the alloy i cant find it on the material anywhere.  using a dynasty 200DX, 160A, 18CFH, ARGON, BALANCE 100, FREQ 120.  i was taking a piece of 1.5 x .120 and cutting it and welding it back togethor and doing the destructive testing.  the last one i did i was pretty happy with the weld it broke the material on the other sides of the weld instead of right down the middle.  but theres still all theese little bubbles in there and thats whats bothering me.  got a couple hay racks to make and i want them PERFECT!!thanks guysMILLER BWE SSMM 251DYNASTY 200DXSPECTRUM 625BLUE WELDERS AND BLUE OVAL TRUCKS......
Reply:I have done quite a bit of alum tig , although I have never used a inverter machine. from what I am reading looks like you are doing everything correctly, maybe turn your argon up a little more (try 25 cfh), are you using a gas lens body?  if not try that as well and slow your travel speed just a bit.  some other tricks are to take a clean rag with your acetone and wipe your rods, you will be suprised on the amount of crap that comes off them
Reply:gas lens body????ill try more argon.  actually why didnt i think if cleaning the filler.....i got the stuff from westair in san diego last time i get stuff from there that rod is nasty dirty made some passes with no filler and the welds come out shiny.  last time i was gonna get electrodes from there they were stained with stuff i got some form arczone and they look like they had been polished.  thanks again ill give that a shot and let yall know.MILLER BWE SSMM 251DYNASTY 200DXSPECTRUM 625BLUE WELDERS AND BLUE OVAL TRUCKS......
Reply:I have the same problem.  Also seems line the aluminum melts shiny but when you add the rod a dark gray crust forms on top of the new bead.
Reply:gas lens body on left  /   standard body on right  ( the gas lens body in pic is ready for trash, spatter fused in screen, just overall bad shape)  some people swear by the gas lens on aluminum, I usually use the standard one myself
Reply:using a standard.still having the porosity issues tried playing with the balance and the frequency but ended back where i was originally.  i now know how to form a ball on the tungsten....turn the balance down to 50% that will do it there.  i can even see black crud floating in the pool.  i dont get it.  i even tried the aluminum wheel cleaner i use on my trucks that made it better but its still not what its supposed to be.  it helped a little kickin a little more gas in there and cleaning my filler but......dang the filler was dirty...MILLER BWE SSMM 251DYNASTY 200DXSPECTRUM 625BLUE WELDERS AND BLUE OVAL TRUCKS......
Reply:I dont know about inverters, but I usually run the ac balance at about 6 or 7 on the dial on miller syncrowaves ( I guess that is 60% or 70%)  also you mentioned when you ss wire brush the alum it is shiny, in all my experience's when I ss wire brush it it turns kinda to the dull appearance, I think you my be just polishing the metal and not really cleaning it, your bristles may be worn out on the brush, try a new one, invest in a ss rotary type brush that you can chuck up in a drill motor, preferably high speed pneumatic drill motor  sounds like a base metal cleanliness issue
Reply:What about plastic wheels?  The ones that have a scotchbrite disk, are they any good?MillerMatic 210 MIGSyncrowave 250 TigBluepoint/Victor torch set
Reply:scotchbrite discs also do a good job in cleaning, but dont skip the ss wire brush step after the scotch brite, than wipe down with a suitable solvent, MEK, MPK, ACETONE
Reply:ill try getting it cleaner.  thats what i meant by the shinyness of the aluminum its nice and bright, has a dull/matte finish but very bright colored.  i have been using a ss brush in a 1/4" air grinder i use about 1/2 can of brakekleen when i get a new wheel to get all the mill oil out of it.  ill try to getter cleaner.  i heard some guys were using a particular flap wheel that was designed for aluminum then using the ss brush i cant remember what it was though.thanks again for the help!!MILLER BWE SSMM 251DYNASTY 200DXSPECTRUM 625BLUE WELDERS AND BLUE OVAL TRUCKS......
Reply:I have a dyn 200. Turn you balance to 68 to 70. Turn you argon down to about 17 cfh. Your amps seem a little high. Set it around 130amps. You are too hot causing the grainy look. The freq. should be about 110 for fillet welds.Also try 5356 filler rods they have less silicone content than do the 4043's. Inverter machines seem to bring the silicone to the top and you will get the little tiny voids in there. Post some pics. I was having the same trouble you did until I tried 5356 rods and moved a little faster. The results looked like the beads were polished and no porosity.   T.J.www.tjsperformance.com
Reply:here are some pics of a alum plate i ran today on a snycrowave 350LXbase metal is 6061 T6 .063"filler is 4043 3/32"pure tungsten  3/32"amps set at 150, using foot pedal so can adjust as neededa/c balance at 70argon at 20CFHspacing of weld is a little far apart, but hey I was in a hurry and just screwing around        this pic is the penetration side
Reply:nice ill give that a shot, ill pickup some more filler tommorow.  thanks again guys!!!MILLER BWE SSMM 251DYNASTY 200DXSPECTRUM 625BLUE WELDERS AND BLUE OVAL TRUCKS......
Reply:I'm not an expert, but I've had similar problems before and cured them by changing out to a new tungsten. Good luck.
Reply:Here is a pic using the 5356. The pic is not that great. The weld came out nice smooth and shiney. This part has was untouched after welding.T.J.
Reply:TJ i was checking out your web site, you do some very nice work. Great job on that flat bed dump, looked like a fun project  very nice
Reply:Originally Posted by elderthewelderTJ i was checking out your web site, you do some very nice work. Great job on that flat bed dump, looked like a fun project  very nice
Reply:update.....the 5356 made things better but im still getting that porosity, i tried speeding up and it seemed to make things worse.  im just lost here i dont know what to do now....anybody that knows al tig in san diego area????MILLER BWE SSMM 251DYNASTY 200DXSPECTRUM 625BLUE WELDERS AND BLUE OVAL TRUCKS......
Reply:oh yeah 1.5 lan 3/32 tungMILLER BWE SSMM 251DYNASTY 200DXSPECTRUM 625BLUE WELDERS AND BLUE OVAL TRUCKS......
Reply:i use to get gray dull welds welding aluminum. The problem was that i was not getting good enough gas coverage. I played with the torch angle and it fixed the problem.
Reply:I've been reading the posts and have to agree with the one that said to use a gas lens and the other that said to change the electrode. Sounds like the aluminum is really dirty, though. I don't get to do much aluminum anymore, but that's what i would do. Also, adjust the balance so you have more cleaning rather than penetration. As silly as it sounds, this helps out quite a bit. Maybe start at 50% and go from there.Tony
Reply:Who are you training with ?
Reply:Over the years, I have found if you use a little preheat before wire brushing  that it helps breakup the oxide on the surface.  You can due this several ways.  Strike a arc and travel down the seam. dont try to form a puddle. You can also use a torch.  You  do not  need more than 150-200  preheat.
Reply:Originally Posted by barebackjakeupdate.....the 5356 made things better but im still getting that porosity, i tried speeding up and it seemed to make things worse.  im just lost here i dont know what to do now....anybody that knows al tig in san diego area????
Reply:Can you leak test your torch and hose? It is possible you're sucking in air. Double check your torch head. Collet bodies versus gas lenses; an adapter is required to close off back of a gas lens cup on some torches. 20-25 CFH gas flow a must. Aluminum mag wheel cleaner is good for chem. cleaning. s/s wire wheels are excellent. Be careful with pneumatics, air may be oily from lube in compressor.Generally, all aluminum welds have some porosity. It is due to the fast freeze of the puddle. That is actually the reason they used to use Helium. The longer the puddle stays liquid, the more bubbles get to float to the top of the puddle.Good luck.WeldtekI am re posting the pics that I posted in this thread a few posts up, pics somehow are missingbase metal is 6061 T6 .063"filler is 4043 3/32"pure tungsten 3/32"amps set at 150, using foot pedal so can adjust as neededa/c balance at 70argon at 20CFHspacing of weld is a little far apart, but hey I was in a hurry and just screwing aroundthe last pic is penetration side Attached Images
Reply:Make sure, if you're using a stainless steel brush, that your brush hasn't been used on anything else, especially steel.  Feel free to spray your joint down with acetone to clean of any oils present after wire brushing, don't use a rag to wipe it on since bits of lint will turn into black floaties.  You can use a rag to wipe your filler rod clean with acetone, but clip the end since the ragged end of a filler rod can also catch a bit of lint.As to your AC balance, you'll want to play with it to find the sweet spot between cleaning action (extremely important) and penetration.  You absolutely need to have good high frequency cleaning action to get a good weld on aluminum.  I tend to use gas lens on just about everything here, though a regular cup and collet will work fine, gas lens will give you much better gas coverage at the expense of some accesibility.  Then again it's the nature of the work we do here that everything has to be perfect.As to selection of filler rod both 5356 and 4043 are good choices when your base metal is an unknown.  5356 will give you better color match if you will be anodizing, and 4043 will give you a brighter weld with less susceptibility to cold cracking.Kalroy"It's all about the OODA Loop."
Reply:Originally Posted by elderthewelderI am re posting the pics that I posted in this thread a few posts up, pics somehow are missing
Reply:yep
Reply:make sure your high freq. is to the max on the machine, the only reason it is adjustable is so u don't conflict with computers and other electrical devices...etc. Try cleaning and preping your work with stainless brushes only, if that doesn't work pre heat it, THEN clean it with stainless brushes while it is hot.
Reply:most important...... do not pull your filler rod out of the shielded gas when u r welding.
Reply:Re TIG porosityHi: I am a beginner, and I had the same problem. Was using a stainless hand brush and acetone. I chewed up a lot of aluminum before I got it right. I wasn't getting the Al clean enough. I now have an 8 inch stainless wire wheel right next to my welding position. I clean everything within 2  minutes of turning on the TIG. Usually don't even use a cleaner, but it works great. Butt welding .050 1 inch sqare tubing. HTP inverter......Beginner
Reply:Originally Posted by motor mountI have the same problem.  Also seems line the aluminum melts shiny but when you add the rod a dark gray crust forms on top of the new bead.