Sorry to hear about your "education"!
The folks who suggested that you weld short spots and skip around and
take your time are right on. I usually use beads about 1/2" long, and
it should take a few hours to weld a seam 3 feet long, when you allow
time to cool. The actual welding variables, such as wire size, heat
setting, etc don't affect warpage nearly as much as how long your weld
Is it possible for you to grind off the weld? You may find that the
warping goes away if you do this. If you overlapped the seam, which it
sounds like you did, then you should be able to cut the welded area with
a thin grinder (cutoff tool, air powered, that uses a 1/16" x 3"
wheel). Then, you may be able to straighten the edges and try it again.
When I got my 55 Belair, someone had replaced the lower quarter panel on
one side, and they didn't flange it, just overlapped it, and then welded
long beads and warped it. On top of that, it was in the wrong position
and didn't line up wit the rocker panel. I wound up cutting it all out
and welding in a new panel, and it's fine now.
59s in AZ
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