helium-aluminum

[tnc110]

I have a 256 on the way. was considering running a mix of helium/argon with a "y" connector for welding thicker aluminum.

Anyone do this? How did it change things?

[welderdude]

Jody from Welding Tips and Tricks has a couple of nice videos on mixing aluminum and helium.

Although I have never welded tig welded aluminum with a helium mix, I have had the chance to weld steel and stainless steel with pure helium. I can tell you that it welds HOT! It makes a huge difference in how hot the arc is. On the flip side, you need a higher flow rate to get good shielding due to it being lighter than air. Helium by its self is more expensive, and using a higher flow rate doesn't make matters any better. The arc is also a little less stable compared to argon and the arc voltage is higher than argon.

I also tried pure helium with my spool gun and 4043 wire. lets just say it didn't work very well. Due to the higher arc voltage of helium, my Hobart handler 210 didn't have the balls in the upper range to supply the higher voltage at a usable current. I was only able to get a slightly usable spray transfer at the highest setting and even this was colder than what i can get with straight argon.

[jakeru]

Absolutely. I love my helium mix on my 200 amp inverter machine (older everlast mosfet machine); it seems to expand its capabilities nicely, as I believe it probably would for any AC TIG welding machine, when any aluminum that is not the thinnest are involved. I find myself using it for pretty much all my aluminum welding now. I would consider switching to pure argon though, for welding aluminum that is about 1/16" or thinner. (that is much thinner than average for me... I've been welding a lot of about 1/8-3/16 and also lot of about 1/4"-3/8" stuff.

I have kind of "settled" on about a 20-25% He mix, and find that by using that mix, plus just a teeny little 1/16" tungsten electrode, and about 80% DCEN, I find I can do more than everything (that includes in the upper and lower metal thickness range) than I could with pure argon and a 3/32" electrode.

The 20-25% He mix still allows etch cleaning and easy enough arc starts so as to not be a problem (using a lanthanated electrode.) And I can maintain a steady arc even with a blunted (1/16") tip, down to as low as about 18-20 amps (which believe me, still has a *surprising* propensity toward melting metal.) Also, this mix still maintains very good shielding, without needing really very much gas flow rate.

I really feel the combination of high EN%, combined with a helium mix and a small tungsten diameter, offers tremendous heat control (range of heat, and concentration of heat.)

http://www.everlastgenerators.com/fo...with-He-Ar-mix

This earlier thread provides some background info on my Helium setup and initial experimentation with it as well:
http://www.everlastgenerators.com/fo...r-(jakeru-s-19)

I've read that with a helium arc, the heat (along with the arc voltage) varies with changes in the arc length much more than with an argon arc. Maybe that is something behind what makes it weld manually so nicely? (Another dimension of heat control perhaps?) I am not sure yet for all the reasons why it is so nice, but it is.