[sgtnoah]

I got some time to work on tigging aluminum this afternoon and am not sure what I'm doing wrong. I'm decent at steel TIG, but probably have about 10 hours of aluminum seat time.

Settings/Variables:
Miller Dynasty 200DX
200 amp air-cooled torch
15 cfm argon (tried Jody's test for leaks, contaminated gas - electrode stayed shiny)
1.5% Lanthanated, 3/32" Electrode, sharpened, with a small blunt tip, pictured in photo
75% balance
120 hz frequency
No pulse
1/16" 4043 Filler
1/8" 6061 Base Metal
75 amps set on machine - probably using 1/2 to 2/3 of pedal travel

Seems like there is a lot of white crud to the side of the welds, have a hard time maintaining a clean puddle. I'm trying to keep the bead narrow, but it seems like if I back off much on the amperage the puddle becomes dirty (using the reflection of the electrode tip as a reference here). At the end, I let the heat get away from me, but nowhere else does it look very good either.

Wondering if you would share your thoughts on this. I've watched and re-watched Jody's videos, but I must be missing something

Thanks,
Pete

[ajlskater1]

Is the white stuff floating inside the puddle or just on the finished weld? If it's in the puddle make sure your wipe the material with acetone. To me it looks like you are welding to slow and the cleaning action of the machine is etching your weld brad, 75.amps is extremely low for 1/8 inch aluminum. For me I would run around 225.for full penetration. I think if you turn the amps up.and increase your travel speed things will start to improve and you will grubs lot less etching outside the weld and of the actual weld.

[sgtnoah]

Thanks for the thoughts ajlskater1, I went out to the shop and gave material one more wipe down with solvent, turned the amperage up and tried to speed the filler hand up to match. Beads looked significantly better, but it seemed like I had to add filler at a frantic pace to make that happen! Clearly my technique needs work, but there is something else that I'm missing. Some of the videos show Jody welding low (I assume???) and slow - like the boat prop, and some others. Being new at AL, I'd like to back the speed down and focus on technique. Not sure if this is possible, and any thoughts would be much appreciated!

-- Pete

[ajlskater1]

Ya you can do that as well. I think Jody used 125 or 140 amps if I remember right on his.full penetration butt welds for 1/8 aluminum, that should give you a.nice slow and steady pace. One thing to they may help you is I noticed you are using 1/16 filler. You might want to try to.go up to 3/32 till you get more comfortable feeding and dipping. One thing I do aluminum when using a,small rod is to push a,little extra rod per dip so you get the.nice coins like you would with a bigger rod. I personally just like to go fast and use smaller rods. Hope that helps you out. I would definitely try the 3/32 rod.

[ajlskater1]

The boat prop one was a build up job and those jobs you tend to have to go slower and colder cause your goal is to not really penetrate but build more material.

[Otto Nobedder]

Pete,

If you're accustomed to steel and stainless;

You're right, you have to feed a boatload of aluminum filler into the weld, compared to what you're used to. This is a common problem for people moving from steel to Al.

Steve S

[Nils]

ajlskater1 is all over this one. Bump up power, clean her good, larger filler rod, run a little quicker, and you'll be styl'n!

[sgtnoah]

Thank you all for the tips... I 'll try to post a pic by the end of the weekend and we'll see if any of it sunk in!

-- Pete

[nova_70_383]

by any chance was the material in service? looks like dirty metal or cast to me.

[sgtnoah]

Thank you all for your thoughts, they were most helpful. I spent some more time practicing, and things are starting to progress. Time for more seat time to work out the bugs!

[ajlskater1]

Glad to hear. Seat time is the best thing for someone learning