Quote Originally Posted by LeftHander View Post
You can forget using OA on autobodies. Somewheres about the early-mid '70s the alloys used were changed. You might be able to fuse it together, but it will be very brittle. At some point the insurance companies told the bodyshops, if they did not have a mig welder on hand, that they would not be paid. They got tired of cars falling apart after being welded with OA. (Dad was in the autobody business for 60+ years.)

I'm looking for further input on this question. It seems strange to me that you could weld chrome moly 4130 or 304 stainless (with flux) with OA, but not the alloys used in auto bodies. Can anyone explain just what alloys are used and what the difficulties might be. I want to weld some patch panels on a mid-80's Toyota pickup bed (bedside). -- Matt