TIG Torch Question

PHPaul · Dec 31, 2018

I'm gathering components to try my hand at TIG welding aluminum.

I've been TIGing mild and stainless steel for a while so I'm not a complete newbie, but...

So I ordered the appropriate 1/8 diameter 2% ceriated tungstens and collets, along with some Al TIG rod and new stainless steel wire brushes for cleaning.

Unfortunately, I didn't think about the collet body needing to be upgraded to the 1/8 size as well. I have the appropriate parts on order.

My question is, seeing as I'm just getting started and fully expect to turn a lot of perfectly good aluminum into smoke and scrap before I get the hang of it, can I get away with reaming out one of my 3/32nds collet bodies to accept a 1/8 tungsten (with a 1/8th drill bit), or is there more to it than that?

Gary Fowler · Dec 31, 2018

When I used to use high frequency TIG to weld aluminum, we use pure tungsten. We put the machine on reverse polarity (like you would stick weld) struck an arc so the tungsten burned up and made a ball on the end. It only take a second to do this. Then put the machine back on straight polarity and you are ready to go.

Pure tungsten makes for a more steady arc than the 2% thoriated or ceriated tungsten when using high frequency.
As for drilling out a 3/32" collet, maybe if you can hold it perfectly straight but I suspect that you will only screw up the 3/32 collet. Just wait till you get the 1/8" and some pure tungsten would be my advice.

sandman2234 · Dec 31, 2018

Hello PHPaul,
The 2 percent is probably a red color paint to denote. I always used pure, which is green... when doing aluminum.
You didn't say what style welder you were going to use, just wondering, because a machine that welds mild and stainless won't always do aluminum. Your machine may have a Hi-frequency start for when doing mild steel or stainless, but aluminum requires a full hi-frequency running all the time. (unless things have changed since I did it). You can scratch start stainless or mild steel, not so with aluminum.
Tig welding aluminum requires a little stronger lens to protect your eyes, as the reflection is a little more severe. I used an 11 .
The mild steel you tig is easy to tell when the temperature is getting close to the right temp by the color. Not so with aluminum. You will start heating it, and then apply a lot more power (I used a foot pedal) and then all of a sudden the puddle just falls out of the material. You have to really watch for when it starts to puddle, isn't an easy thing to see at first, when learning.
The size of your tungsten is directly related to what you are welding. You should be able to purchase the correct collet for the size tungsten you are using. Double check to see if they are available in 3/32 also.
The gas will be different also, sometimes. I always used pure argon for aluminum, but when you get really good at it, and want to impress your friends with your welding expertise, grab a bottle of helium. It takes a lot of it, since it floats off very quickly, but it does make the weld look great. (Oh, even with argon, you will have to turn your flowmeter up a little bit more over steel and stainless. I even used a different ceramic tip for the better flow of the gas while welding.
I was able to experiment a lot using different gas and tips due to having a contact with a welding supply company that I did work for. One of my benefits was free gas, and they always gave me any extra's or clearance stuff for free. All I had to do was supply my own bottles, which is why I own so many bottles even to this day.
David from jax

sandman2234 · Dec 31, 2018

Gary beat me to it, lol.
David from jax

PHPaul · Dec 31, 2018

I have an ancient Miller DialArc HF and it does have a constant HF setting.

I have a bottle of pure Argon that I swap back and forth between my MIG welder and the Miller if I'm running TIG.

I also have Red (thoriated) Green (pure tungsten) and Gray (ceriated) tungstens available.

My Miller helmet has a darkness setting that I can adjust.

I did a little aluminum TIG work when I worked at the cannery, but that's been a lot of years and with a much newer machine.

Motorboatin · Dec 31, 2018

You can weld aluminum with any of the tungsten you have as long as it's 1/8" but ceriated and lanthanated works best. Pure is going to ball up fast and flutters when the amps get high enough to weld anything over 3/16 thick unless you can adjust the shape of the arc but that only gets you 20-30 more amps. Lanthanated stays clean and is stable plus it's cheaper than ceriated

Just use what you have until you need to buy more

yomax4 · Dec 31, 2018

Remember, Only the Transformer welders require you to Ball your tungsten. Most Inverters will do better with it pointed. When you can run a pointed tungsten, You will have a smaller heat affected zone which means you don't heat up as much of an area as you do with a Balled up tungsten. This lets you do thicker material with a smaller machine. If you have a Transformer machine I'd suggest Pure (Green Tip) But if you have an Inverter I'd suggest 2% Lanthinated (Blue Tip). Almost No chance of boring out a collet but you probably could bore the collet body. Why not just use 3/32 tungsten if you have it. good Luck.

kenmac · Jan 1, 2019

I have been using the gold. 1.5% Lanthinated. Seems to be doing ok

PHPaul · Jan 2, 2019

Well...crud.

Drilled collet body worked okay, but it's pretty apparent that TIGing aluminum won't be added to my skill set any time soon, if ever.

I tried every combination of tungsten (both size and composition), stick out, tip shape, polarity, amperage, and arc length I could think of without success.

I cleaned the aluminum by sanding off the oxidation with new-unused 3M roloc discs, and then wiped it down with acetone.

Problem is primarily two things:

1. I can't see the puddle. By the time I DO see the puddle, it's too late.

2. I shake like a dog passing peach pits and wind up sticking the tungsten into the work. Also makes it difficult to move the torch smoothly.

I never got far enough to try dabbing the rod (started getting mad and quit before doing something stupid) but trying to move the torch with one motion and dab the rod with the other hand using a completely different motion is going to be a challenge.

I haven't given up, but @ 68, I know myself pretty well and I seriously doubt I have either the patience or the persistence to master this one.