ok ive been welding aluminum for a while now (but still no pro) but have never run into this yet. i was welding some practice joints just to get my speed and heat down for the material to try and cosmetically match some beads that are already on the piece. anyway the first two joints i did came out shiny and normal but then the bead got gritty looking. the puddle looked normal and shiny but as soon as i move the torch for the next dip i see it cool and the grit kinda rises up to the surface. ive welded dirty aluminum before and this seems different but i cant figure it out. the settings stayed the same between good weld and bad freshly prepped tung, and parts and filler cleaned with acetone. heres two pics of the beads, good on top and the gritty one one the bottom, its a little blurry but you can still see the texture on the surface of the bead, mostly on the trailing edge of each dip. ill check any suggestions asap as i need to get this piece done pronto. thanks for all the help.

oh and the tape is just so the camera would focus.

 

anybody? give me something to check?

 

what is it that you are welding?

 

the piece in the pic is a section of 4" tubing im using for a cold air intake for a Cadillac cts v but i have a bunch of other scrap AL ive been using to try and figure this out and the "grit" is showing up on every AL piece i weld from thin sheet to 3/16" with everything clean and i even started with a fresh bottle of argon today (prob started yesterday, thought it might be due to low tank) , ive done everything i can think of, ground and balled new tung, cleaned part and rod, cleaned gas cup, i keep the table top grounded and never had a problem with it before.

after i got tired of pushing shitty beads i moved on to a stainless project and had no problems welding it clean and neat, the prob just seems to be on aluminum??

amps were set at 100 with my foot a little over half into it, flow at around 15-20cfm and the balance ive moved from one end to the other with no change.

 

I have run into similar problems in the past. If you are using a gas lens try putting a new one in.

 

Why does it appear as though there is no cleaning action?

 

because i polished it afterwards so the camera would pick it up better. i moved the balance all around just to see if it would change anything but it didn't.

and as far as the lens im not using one just using a standard cup but i did take the cup off and cleaned out the inside of it, but still no luck.

 

Did you recently paint anything in your shop? Coud be a layer of something covering the aluminum pipe. Leak in your gas line somewhere? Did you say this same pipe used to weld fine? GL

 

So you are using a collet body?

 

Are you using cheap aluminum? I've see that before on some of the cheaper AL's....

Have you tried a new tungsten?
Inverter or transformer machine?

 

x2 on the cheap aluminum! Try wire wheeling with a sst brush to prep the aluminum.

 

those good bead, bad bead pics are from the same piece (different joint). all the other scrap pieces i used to test on were also previously welded on with no prob.

and yes i pulled out a brand new red tungsten, ground to a point and balled the end.
i cant wire wheel the piece cuz i need it to be polished but i did clean it with acetone, and on the other scrap pieces they WERE wire wheeled and then cleaned with acetone 30 sec before being welded but the bead is still gritty?

?? syncro 200, you tell me. lol.

 

That's a transformer machine.... with them you "should" use green. That may be the problem, but I kinda doubt it. I have tried red in the past and didn't like what it was doing, but I don't remember exactly what I didn't like about it. lol

 

the machine is only 6 months old it came with one orange tung and i bought a 10 pack of red as per the advice of the welding supply shop guy. i have the orange laying around somewhere but the red is really all i ever use. and like ive said the before and after, as far as i can find, were the same settings, epuip, gas, filler, etc.. i only started changing things AFTER the problem started to try and fix it. i have used green in the past on a different machine but iv'e never had a problem with the red till yesterday.

 

does your machine have an ac balance setting? this can help with that too, i also only use grey with pretty much everything but i didnt really like red when i used it. might try switching, also could be a bad bottle of gas if its all of a sudden.

 

Too much heat or wrong filler

what size filler rod are you using and how thick is that material?

 

Did you refill your gas bottle before you got the gritty welds?

 

i find alot of impurities can come from within the filler rod

 

yes i have ac balance and ive moved it from 0-10 and everywhere in between and its not helping.

i used 3/32 and 1/16 clean filler and this is happening on any thickness material from thin sheet to 1/8 but if it was too much heat the bead would be flatter

the problem started towards the end of my last bottle so i thought that might be the cause but the situation is the same with the new bottle

i suppose it could be "in" the filler as i cant clean inside of it, but it all came from the same box and ive used multiple rods both before and after this started

i wish i could take a video of this happening but the puddle forms normally and when i dab the rod the bead forms normal and shiny but as i move the torch forward, the bead i just dabbed kinda shrinks down a little and the grit kinda rises up to the surface

should the flow be higher than 20cfm?

 

Bad argon will do this. I had the same thing happen after a bottle change.

 

but it started with my last bottle with which i previously laid good beads, and still is gritty after switching to a new bottle

 

i have had this problem and was told to much heat. but i rarely do AL. so idk for sure

 

well unfortunately i think this is going to remain a mystery for now. i was just running more beads to test stuff out and the problem seemed to gradually "fix" itself in the middle of a filler rod, without changing any settings.

i was kinda thinking the contamination (if thats what the problem was) was coming from the torch somewhere and maybe it finally got burnt out, but who knows, its gone and im happy for now. thanks for all the suggestions.

 

could also just be dirty contacts for the high frequency?

could it be more like pitting instead of contamination? that would def be a high frequency issue

 

check your air hose? sometimes (rarely) you will develop a pinsized leak that will allow air to get sucked into your shielding gas and contaminate it ever so slightly. could also be a bad batch of tanks seeing as your getting your tanks from the same supplier? you may want to try another source? could also be cheap/dirty metal

might want to clean your tungsten/filler/workpiece before welding. also, check the cleaning/penetration balance on your machine.