I've got a local guy willing to weld a new plate on my subframe where the body bushing has rusted pretty bad. He wanted me to find out what type of welding rod he should use? He plans on stick welding the new plate to the frame.
the guy welding it for me works for a heavy equipment company and he owns a stick-welder/generator. The stick welder is the only welder available to him to transport over my house to do the job. I would assume the stick welder is good enough -- they use it to weld on heavy equipment. I really don't know anything about welding.
Just tell him not to run a continuous bead. He should only run about 3/4" of bead and then let it cool down. I hit with with compressed air to expedite the cooling process.
If he runs it all at once he'll warp the frame/unibody. Just as a test (two years ago) I decided to see how long I could run that stick before the frame warped - it was a bad truck frame. I made about 1 1/2" before I heard a loud PING. That was all it took for it to warp.
Relax with the stick welding. I've repaired many frames that way and never had a problem. Of course, when I was doing my own I only ran 1/2" at a time. Now I MIG weld them.
I think stick welds have a higher tensile strength than mig welds anyway. Even though personally I would have an easier time mig welding it especially if it is still on the car and you have to wind up welding over head. The other guys are right about being careful not to warp the frame.
An experienced stick welder will do the job just fine. The thing to watch for is high heat which might burn through or warp the subframe. As Bob said, use a mild electrode that isn't real deep penetrating. I would recommend the 6013 rod in 3/32 or 1/16". This is a good rod to use for multi-purpose things.
wow, thanks alot for all the helpful information. The last piece of the puzzle is to determine what type of metal plate to use. My thinking is to cut-out the rusted body bushing hole and weld in a plate then drill a new hole in the plate. What thickness plate should I use and of what material should the plate be?
Repair plates are available at the usual places (Ames part# FS745, Clasic Ind., etc). That would be the easiest way to go. They are the right size, shape, and have the holes drilled. Just weld them in. I've never done it but that looks like the way to go. Others have cut a big hole in the existing mounts and welded in big washers.
