[TheForge] Aluminum welding

[Woolley]

John,
Why helium?  Isn't argon used for AL mig?  4043 is for 6061 AL.  Are you 
sure the beam is 6061?

Bill Woolley






John Allen wrote:
> I welded an aluminum dump truck dump body frame rail together since a
> 4 foot section had to be replaced at the pivot end. I replaced the 6
> inch I beam with a new one and I welded it together. The owner has
> contacted me that the weld broke. I fixed it and gave it back. He now
> said it did it again. It is breaking from the top of the beam down.
>
> I made straight cuts and there was about a 3/8 inch between the old
> one and the new piece. I mig welded the outside after I cleaned the
> joint with a brand new stainless steel wire wheel and then aluminum
> cleaner, muradic acid. I welded it at proper settings and helium gas.
> I even cross stitched weld over the vertical weld to improve strength.
> I am using 4043 3/64 wire
>
> After it broke the first time, I asked other welders what I did wrong,
> they don't know. I am loosing my mind trying to figure it what I am
> doing wrong. I do not have a welder heavy enough to put out 250 amps
> to tig weld it but I do have a 302 trailblazer that I could run 225
> amps to tig it. I don't know what to do besides replacing the entire
> beam and eliminate the weld.
>
>