I've ended up with a load of questions in my mind about MIG stainless
and no answers.
So what's you views on MIG'ing stainless?
Here's the story, FWIW...
I went to a trial weld session for a job, where welding was MIG'ing
stainless steel. 12Cr sheet with 308 welding wire. Gas Argon
30%Helium ~1%Oxygen. I was told what to do - machine settings - but
also found the stainless different. I was left unsure what's their
conditions and what's about the stainless. The MIG stainless weldpool
seemed "gloopy" and far less willing to "flow-forward" and "wet" than
common "black" steels. On the other hand they had me weaving to
build-up and spread the weld - fillet welds. Whereas MIG'ing
structural steel I "tune" the conditions to run straight, fast. With
a hotter condition for the stainless which enabled me to run straight,
the difference disappeared a lot.
I found the whole trial weld thing exhausting and fell asleep on the
sofa promptly on getting back.
Spatter proved to be a pain they are always mitigating with
Waking up in the morning, I was thinking - for this stainless, should
you be following the "rules" for general structural steel welding and
chase the conditions to the highest heat the weld will take without
undercut and charge along straight down the joints, letting it flow in
as it will? Welds are all on about 4mm / 5/32-inch. So you wouldn't
be changing conditions all the time.
Sorry I've ended-up with no findings of my own to comment.
5 years ago