Another Aluminum thread........

[earthquake5683]

I tried not to post this as I see alot of people asking the same questions, but I cant seem to find anything to solve my pounding head. I understand that if it was possible, then people would just do it other ways, but here I go.

Most everyone says to use AC Tig for ALUM, but my Lincoln SP175T Mig has a liner, ect to weld alum. As everyone knows, MIG is DC. Also, people say that you can TIG DC for ALUM, but say that you should use TIG. Is this for penatration, or what? What would the limits or characteristics of the AC and DC (Tig/Tig and Mig DC) be for these types of welding.

Maybe this will clear it up for some of us.

Thanks,
Joe

[Rod_Burner]

Al Does not like DC you can use DC But the AL must be thick and you must use Heilum for the Sheilding gas Tig works best and AC gives you better results. Remember Al is far more forgiving than any metal I have worked with.

[Conrad_Turbo]

AC helps clean the base material when TIG welding.

[Broccoli1]

Not exactly what you are looking for but if you search around the site you'll find an article regarding AC and DC.

I remember reading one but can't fnd it now.

http://www.thefabricator.com/Aluminu...cle.cfm?ID=613

[hankj]

MIG on aluminum works because it runs DCEP. The negative potential on the work provides a natural cleaning action due to the movement of ions from the work to the elctrode. 100% argon is needed.

DC TIG welding of aluminum was the first process used, named "Hieliarc" beacuse of the Helium shielding gas. Later developments produced AC processes that used argon, a much less expensive proposition. The introduction of AC to alumnum welding also permitted the welding of thin material with the TIG process.

Hope this clears it up some.

Hank

[earthquake5683]

Yeppers.....I think i got it now.