stupid steel vs es 70 s (mig welding)

by roy dehaven
(albuquerque NM)

I got a nice manager chair and eventually broke about 3 years later. The break begins where the "collar" is welded with the metal bracket for the bottom seat. I assumed both metals are the same, based off existing weld (in cranny that hard to see). I noted it had two lines of weld beads only one seem to be cracked.


with 75% 25% (C25) gas and es70s-6 wire, so welded them together on the bottom instead of the cranny area..

the weird part... about six months later chair broke again, this time collar-bracket cranny weld completely broke allowing whole collar to come out. I took close look at the welds. My weld did penetrate the collar nicely. but did not penetrate the metal bracket. I looked at the cranny area weld (since it is out, becomes visible), I noticed same thing... the collar had good penetration, but not the bracket!!

Suspecting manufacturer did poor material selections. I called them to spec out the bracket. They do not have the information.. CHINESE made!!!

so back to the issue... is there other recommended wire to try (other than the ES70S-6)?


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roy,

the wire is most likely not the issue.

i have welding several chairs like the one you describe. some of them even have pot metal parts.

pot metal will not weld to steel no matter what so if that is the problem, its done.

but if it was previously welded, it might just be paint that is keeping the weld from penetrating.

or maybe there is something in the design that keeps one of the parts from being grounded.

good luck