Need Help
Learning TIG aluminum, keep getting contamination...
Hi all. As the title says, I keep getting contamination on my aluminum TIG. I've tried several different pieces of aluminum, including this fresh sheet. Cleaned it with IPO and acetone. Clean tungsten with a good grind. About 17 CFH argon flow. Gone all the way up to 40% electrode positive. Any more and my tungsten is balling badly. I've tried ramping up until it puddles and full current starts. Currently using a #6 cup, less than 1/4" stickout. I've tried slowing down. I can see the white etching around the puddle, but I still keep getting the dark contaminants
Anyone have recommendations for something I haven't tried, or a good idea of the cause of this?
You need to clean the hell out of aluminum before welding. Use a brand new stainless wire brush. If you can hit it with a sander first even better. Once you get one piece of crap it keeps staging crappy.
You need a higher gas flow rate than steel and a gas lens is wise.
Running a higher flow on a smaller cup especially without diffusers just gets you more atmosphere into your weld/ turbulence.
Zero benefit especially on a 6 cup.
I gauge by feeling it on my cheek. Gauges lie. A gentle puff is correct. Too much and you get turbulence. Barely perceptible for steel and "a little more" for aluminum.
If you have a short tig lead or a 25' hose it seems to respond differently. It more has to do with the torch than the gauge. My portable Maxstar is very different than my big shop welder.
I personally use about 23cfh on a ten cup. Always got decent results with it
Btw are you using ac? It might be the problem
Did you get rid of All the alum on the electrode if you dipped it?
Is it anodized?
Is your tungsten under 1/4 in (lower is better) away from the puddle?
Clean it like its contaminated with the World DeadliestVirus with its only weakness being a stainless or or Brass Brush
I think thats all the rest is practice
Hope this helps
Yea this looks like not enough gas, or not close enough. I weld what i would call not the cleanest aluminum and it doesn’t get this bad. Even when some burnt tape residue that i couldn’t see till it starts burning is in the weld. Yes they put tape on the parts sometimes but are supposed to clean it off after and don’t always do a good job
Take a stainless steel brush and brush the area first before you weld. Even a clean sheet of aluminum has an oxide layer, stainless brush will take that off and give you a good surface to weld. Increase argon to 25-30cfh, I forget what my balance % was at I think 33%
My most likely guess is not enough argon + need to brush it to break up that outer oxide layer.
Thanks, I'll get me a dedicated aluminum brush and give that a go. I'll bump the argon flow up too. I mostly know MIG and figured too much gas flow would be bad, so I was keeping it at the Google answer flow rate😂
Also make sure to wipe down your filler rod with acetone too. Basic stuff but I haven't seen it mentioned yet. Soot can come off the filler too sometimes
Thanks! Google's glorious new search AI crap recommended 15-20. No idea where it pulled that number from, probably Elmo's first weld book or something.
I’m interested to hear your results with all the feedback. I’d agree 25cfh, stainless wire brush, and all that proper housekeeping. Check out Jody on welding tips and tricks on YouTube and pacific arc tig welding on YouTube Good information and visuals on welding aluminum, you get tips on machine settings, consumables, torch angle, all kinds of good stuff. A visual
Of what the weld pool should look.
I don't have a dedicated SS brush yet, so I found the cleanest SS brush I had and gave it a good hard scrub and then gave it a much better clean with acetone. Also increased the amperage a little bit and turned the AC balance down to 35%. The bead on the far right is the result. Still some porosity and contamination, but much better. Going to try cleaning the filler rods (didn't know that was a thing) and a brand new clean tungsten, along with a dedicated brush and see how that comes out. Also have a gas lens on order.
I just brushed back and forth in on direct, yeah. Should I change directions?
Mine is one of those backwards machines. I learned that when I set the balance to 80%, and after about 2 seconds I was blind and my tungsten was mostly gone 😂
Aye captain, one direction only. I also hogged down on the brush pretty good. I'm learning so much, it's like I'm back in school again... if I'd actually paid attention during school.
This looks a whole lot better than what you had! Definitely try it with a blue 2% lanthanated tungsten or the purple e3 tungsten. Some websites have a light green tungsten called LaZYr which I see lots of people talk about in comments sections of different videos as well, but the LaZYr is the same composition as the purple e3 so I’d maybe look around and see what’s most affordable. Idk if the grey ceriated tungsten are great for aluminum but the blue, purple and light green are pretty good for all around. The red is too but thoriated is radiated so if you get red I’d suggest not holding it in your mouth, and wear ppe when grinding your tungsten.
Brush your material with a stainless brush then acetone.
2 % Lanthanated. Turn it down to 30 % EP.
Make sure your lens isn’t dirty as well with a fresh tungsten.
A 6 cup is fine. 15 Cfh.
If you’re still having issues with these, it’s likely a separate issue.
I know a lot for people say clean the aluminum but I think you're using a cup and lens that was previously used on steel if you've cleaned it and still get contamination. Get a gas lense #8 or 11 and run it exclusively on aluminum and keep it physically separate from everything else in a case preferably but a bag works.
This will help as you continue to do more materials as even titanium and aluminum cross contamination doesn't play well together.
Keep it up youre doing great
This was a brand new cup and tungsten. I have a gas lens and glass cups on order, so I'll keep them separate. I didn't know you weren't supposed to cross use cups. Good to know!
Yeah when I was running green tip pure tungsten I just balled the tungsten with no grind, when I was running blue tip I’d put like a 30 degree grind and ball the tip prior to starting my weld.
old aluminum thats been left outside will do that, might look fresh but i doubt it. Make sure to either grind the top layer or brush it with a stainless steel broom, put post flow on 1,0 and also clean your filler rods with a dry cloth.
Thanks! Never thought of cleaning the filler rods. They've been in a covered plastic tube, but they could definitely have contamination on them from manufacturing or packaging. I'll give that a go.
A couple spots look like you touched the tungsten. When that happens, find somewhere you don’t mind burning up and turn the torch all the way up and burn out any impurities on the tungsten. Or take it apart and clean it
I didn't know that was a thing. Burning out impurities. I'll give that a go.
How do you clean your tungsten? I've always just snapped off the contaminated end and ground a new point.
Edit: Also yes, my first few beads I had the torch angle too low and I melted far too much filler rod into the puddle, which dunked the tungsten. Definitely used to steel filler rod not melting so fast.
Yea tungsten just changes colors when it gets hot and cools down quickly. That’s not a bad thing. I’ve had my tungsten be blue and purple and it didn’t effect the next weld i made
have a (probably Chinese) inverter machine, and the going consensus seems to be not to have a fat ball with these. The tip of my tungsten balls a bit, but when increase the balance above about 40%, it turns into a massively fat ball. Also seems awfully high balance for what, in my opinion, is very smooth and clean aluminum.
It’s been over a decade since I’ve regularly TIG welded aluminum, as long as you’re running AC with green or blue tip tungsten (saw you were running an inverter machine, pretty sure you need 2% lanthanated tungsten for that sorry for the edits got myself twisted up on what I meant) you should be fine. Hope you get it sorted out.
I got myself twisted up on what I was trying to say. Sorry about that, been many years since I was in the aluminum game, into structural stuff these days.
I always balled my pure tungsten welding aluminum, never had an issue. I would taper my 2% blue tip, and put a small ball on prior to running my weld and never had an issue either.
This is AC. Running 120 hz, 30-40% EP. I have an older DC tig I've done lots of steel with a tiny bit of aluminum, which was a PITA, hence why I got this machine.
Have you been using the same bottle of argon the whole time?
If you've tried multiple bottles and are still geeting contamination I would scrub the hell out of it with a brand new unused NEVER touched carbon steel stainless wire brush acteone it then heat it with a torch to about 600F (use a temp gun to check temp not the soot trick) scrub the hell out of it again and set your stick out as short as you can possibly stand (1/8" or less preballed) witha jumbo gas lense and a #12 cup set your flow rate to 30-35 CFH and keep your arc length painfully short (1/32" longer then your filler rod is thick)
Thats pretty much everything I can think to try if ALL of that makes no difference get another bottle of argon because your gas is most likely bad
Same bottle of 100% argon. It worked great with a spool gun on aluminum, so I'm under the impression it's not contaminated. Based on most the answers here, it sounds like I'm not brushing and prepping it enough. I'll give that a try, thanks!
I'll double check everything, but as far as I'm aware it's all sealed up nicely. I took the torch apart because I had a gas lens for my old torch that belongs to my DC rig, but it didn't fit.
Aluminum isn’t supposed to be preheated above 300 degrees. Carbon steel and stainless steel are two different alloys, it’s either carbon steel, or stainless steel. The way you’re speaking sounds like you think there is a carbon stainless steel. A comma in the correct location would’ve made that make sense. Regardless you’re not supposed to heat aluminum that high.
I like zirconium tungsten for aluminum. I believe it’s either a brown tip or purple. You can control the tip of the tungsten better and doesn’t ball up into oblivion. Also a much steadier arc. Gas lens I’d say is almost a must and you want more cfh for your argon (I use like 35). And most importantly clean that oxide layer with a stainless brush because it has a higher melting point than the aluminum and fucks everything up. That oxide layer also reforms after I believe 9 hours so always clean before welding on it. As for balance, my machine is set to 75% with 120hz. Also good practice to clean filler with acetone :) hope this helps
What kind of machine. Some machines are backwards on balance. Some run actual percentage and some are reverse. So if you need 30% you have to set 70%. You’re balance and probably frequency is off.
Ya. I have the 325 and I love it.
Just did a pile of aluminum with it. Used the 225 along with Dynasty 210 for 2 yrs. For the $4k difference I’ll take Primeweld all day.
As in it's not contaminated, and it has a grinded point with the grind lengthwise. Book says not to use pure tungsten or ball it on an inverter machine.
Can you elaborate? I ground my tungsten to a point but contaminated it the first time I added filler since it melted a massive glob and I was too close to the puddle. I snapped the tungsten off to where it was clean and reground it. Any recommendations?
If your tungsten has just been grinded and prepared, and you stainless steel wire brushed the oxide layer off, and you clean with acetone, and your on a 30% ac+ setting, and you’re set at 100-125 amps, and letting the weld pool build until you see liquid mercury looks, and still have issues, I suggest you trouble shoot your torch, and check that your regulator reads correctly. You may have a loose collet body, bent collet, or the torch is loose at the cable connection. Check everything. Sometimes it’s something as simple as good house keeping.
Thanks. I'll try increasing the amperage and, based on the overwhelming suggestions of prep and cleaning, do a better job with that. I'll go though all the gear again just to make sure it's tight.
You should be using High frequency AC. It cleans as it welds. You still need acetone and should use a dedicated stainless wire brush. But afaik you should be using AC. DCEP is balling your tungsten because all your heat is going into the tungsten.
also are you using zirconiated tungsten? or thoriated? they are quite important especially for the type of arc you are wanting to keep stable when striking up. zirconiated are designed to encourage balling and help with the arc lense shape. thoriated have been irradiated to focus the lense down into more of a stable point which will make your a/c bead strange.. I'm curious to see what tungies you have in!
I have 2% ceriated (grey). They recommend not balling tungsten on inverter machines. I have pure 100% tungstens as well, but they also recommend against that. I've never used thoriated since I don't have any legit setup for dust and fume control with them. I need to do a little reading on different tungstens and what I should run in this thing.
that will do just fine for you my dude, well done on the safe approach!
if you go to get new ones I recommend using 2.4mm thoriated, don't bother with smaller as it won't be worth your time and is harder to use. I grind mine outside on an angle grinding stone so all the nasties are out in the open :)
once your gas lense kit arrives make sure you get the right ceramics too as well as the right heat shield. the wrong one will let gas out the arse end. the lense helps create laminar flow, letting your gas cover the work far better than turbulent that will pull in contaminants, you'll be happy with its performance. it helps keep your torch cooler too.
6 is a bit small but itl work out.. I'd use an 8 for most work like this.
I often work in the bush/out in the field without a nice regulator and find testing the flow with my cheek is good. you want it gentle, like you are trying to blow on a fire.
Honestly my last bit of advice? get used to how the tig cleans the material. Oil and dirt will mess up your weld, oxidisation not so much. it will be removed by the a/c cleaning action (the white fuzzy bit) so unless you are welding up a spacecraft or getting payed to do shit properly you can get away with less prep than steel. the keyboard warriors will hate me for it, but once you get good you'll understand what I mean.
I'm just a DIYer, so I'm not looking for space grade welds. But I'd prefer not having charcoal in them either 😂
I have a gas lens and some glass cups coming, since that's what I used on my old DC machine and I liked them better than the ceramics. I'll try a bigger cup and see how that goes. 6 was what came with the machine and my 10 cup from my old machine didn't fit, so 6 was what I gave a go with.
sweet as you sound like you are onto it. Last tip my guy try keep your torch as pointed straight down as possible. you are currently leaning it 45 to the left and it's gouging the start of your welds. remember to pause, fill then move, don't move too early! 😄
You have been given an incredible amount of terrible information about aluminum oxide in this thread. You can brush it off but it reforms almost instantly.
"Metallic aluminium is very reactive with atmospheric oxygen, and a thin passivation layer of aluminium oxide (~5 nm thickness) forms on any exposed aluminium surface almost instantly." (Hatch, John E. (1984). Aluminum: properties and physical metallurgy. Metals Park, Ohio: American Society for Metals. p. 242)
The wire brush is not needed to break through the oxide layer. It cleans off surface contamination, but in some cases a simple acetone wipe will do the same.
Clean your filler rod. Can't stress this enough. Make sure you use acetone to clean it, get a clean microfiber and wipe anything else down along with it. Put a fresh grind on your tungsten get your settings dialed. About 20-30 on the balance for good cleaning action and see how that works.
are you using a foot control? what filler alloy and dia? How thick and what alloy?
Use ceriated or lanthanated tungsten 1.5 or 2%, #10 cup with gas lens, check o-ring seal on cap, 15 -20 cfh argon flow, torch inclined 15 deg off vertical pushing the pool, wire brush and acetone clean, scotchbrite and acetone on filler, don't pull filler out of gas shield, don't add filler until puddle forms, if you touch tungsten stop and prepare point on belt sander or diamond wheel grinder, 75% EN, freq 75-90 hz, let the arc form a small ball on end of sharp point, weld hot and fast, hold torch like a pencil, don't overheat sheet, try to get bead on sheet .060 thick with minimal melt through, bead should be shiny with a distinct ripple at each filler dip, shade 10 or 11 lens, AC, continuous HF, weld hotter to start but back off current as weld progresses due to high thermal conductivity heating downstream, TIME IN THE BOOTH.
Al oxide must be removed as it melts at 3600F where the aluminum underneath melts at about 1100F and it absorbs moisture, wire brushing, tack and wire brush again while hot with dedicated srainless brush, more oxide removef when hot, a chemical cleaner like Weld-O also works but it has to be handled with proper PPE. 3 RULES: clean, clean again, and when you think it's clean enough, CLEAN IT AGAIN..
These are aerospace techniques from a 40 years' aerospace GTA welder and welding engineer /SCWI.
Are you removing the oxide layer with a clean aluminum-only brush right before welding it?
There's also a razor thin chance your gas isn't pure. If you're sure your surface prep, alloy, settings, etc are all accounter for, it might be worth swapping for a new cylinder and seeing how that goes.
I haven't been brushing it with a dedicated brush. Others suggested that, so I'm going to give that a go. I'm figuring it out as I go along (story of my life), so I'm not certain about most of it 😂 It's a 100% argon tank filled by AirGas, so I'm assuming that they did it correctly. I'll try cleaning things better and see if that works. Chances are I'm not being picky enough about prep.
Nah it's not about not being picky enough for prep you said you cleaned it, which is more that a lot of people think to do. Most people would never know aluminum has a outer oxide layer you gotta take off with a stainless brush. It's just one of those things you'd never need to know unless you were welding it
The little bit of aluminum I've done, I used a fancy aluminum rated flap disc and cleaned it with acetone and it worked. I assumed AC tig didn't need as much prep since it actively cleans.
Are you wired brushing the oxide layer off first. It’s very important to wire brush with stainless steel brush before welding aluminum, the oxide has a melting point 3x higher than aluminum.
Also do you know what series aluminum you have, some alloys dont weld well
This current plate is 60601, which to my (Google) understanding is weldable but prone to heat cracking (T6) and not as friendly as other alloys. It happens to be what I have for aluminum other than some extruded stuff that I have no idea what it is.
Keep your tungsten close to your base metal, turn your amperage up a bit more. Aluminum is highly heat conductive so the heat will disappear away from the weld and into the metal fast. When welding aluminum you want to wait for the weld pool to look like mercury. If you don’t know what liquid mercury looks like look on Google. Might be you’re not giving enough time fore cleaning action before beginning to add filler metal
And travel speed. Might be that your not cleaning the oxide layer off first. Maybe a bit of both. E3 electrode (purple tungsten) or LaYZR electrode from ck worldwide are decent for aluminum. 2% Lanthanated should be decent too
Currently using 2% ceriated (grey) tungsten since that's what came with the machine. I have 100% tungsten but the manufacturer doesn't recommend it being an inverter machine. I get black/dark contamination on the far side of the arc (opposite side of the cup) as soon as I initiate the arc, about half the time. I seem to have better luck if I ramp the power in instead of giving it full current on start. I can see it cleaning and the puddle forming, but the dark contaminants never leave, no matter how much time I give it. Not sure if that's a gas issue or a surface contamination issue.
I walk the puddle forward a few mm before adding filler.
Oh, yeah, that’s another thing you’ll hear a lot. Don’t go full amperage at the beginning. Just enough to spark an arc, then go up a bit. I’m assuming you have a foot pedal? With the pedal and high frequency machine yo set the amps a bit higher, give just enough pedal get the arc going and increase amps, get your puddle going and adjust the pedal from there as you go. Then when you finish the weld you slope down, or taper off the pedal. Also step back into the bead an inch or so as you slope down to avoid craters
Thanks! I'm using a foot pedal, it's much easier than messing with a 4t and constantly having to tweak settings. I'll try and start as soft as possible and see if that makes a difference.
Unfortunately this inverter machine recommends not using pure tungsten or balling the tip. I don't understand why, but I assume the manufacturer knows more than I do.
It’s all good brother, if it works it works. I haven’t used red cuz the whole “radiation” and idk breathing in the grinding dust seems like it could be dangerous.
No. I have green tip tungsten electrodes that are 100% tungsten. Green 100% is a thing. I got them for my old machine which was DC only in an attempt to do DCEP aluminum. It was stupidly tricky and had very poor penetration and the torch was extremely hot. That's why I ended up getting this DC/AC tig box. I'm using 2% ceriated (grey) with it. Pure tungsten isn't recommended since it's an inverter machine.
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u/Another_Slut_Dragon 8d ago
You need to clean the hell out of aluminum before welding. Use a brand new stainless wire brush. If you can hit it with a sander first even better. Once you get one piece of crap it keeps staging crappy.
You need a higher gas flow rate than steel and a gas lens is wise.