[TowerTalk] [Bulk] Re: welding aluminum

[Jim Lux]

On 1/31/15 8:23 AM, Grant Saviers wrote:
> I agree that "loss of temper" is low on the concerns list for amateur Al
> welding.
>
> Having a MIG or TIG welder capable of welding Al is a lot different
> (speaking from my failures) than having the skill to make structural
> grade Al welds.    It also takes professional grade and high amperage
> equipment given the conductivity of Al.  My Miller Econo-TIG (and me)
> weren't good enough for 14ga 6061, I sold it.  I have complete
> confidence in my MIG steel welds.
>
> It sounds like the 33'x40' H frame design is tube to tube structural
> welds and that may need a professional.  Otherwise, consider Al plates
> and galvanized u-bolts like most element to boom clamps, which also has
> the advantage of it can be taken apart for repairs, etc.  Phillystran
> guys are probably required for that large of a frame.
>
> I very much enjoyed watching a welder demonstrate the latest HF pulse
> TIG Miller welder as he welded together Coors cans.  I think that is
> 0.004" thick Al.  The Olympics of welding for sure.
>

ACtually, beer & soda cans are thinner than that.. and they're thinner 
at the top than the bottom.

http://www.chymist.com/Aluminum%20can.pdf is a fascinating article from 
Scientific American

Where I used to work, TIG welding aluminum foil (0.001") or gum wrappers 
(even thinner) was the challenge..  A very steady hand on the rod and a 
steady foot on the pedal...
(mind you, I can barely weld steel)