I picked up a 1975 Camaro from EBay from some guy that tryed to make it a street/strip car. This guy was somewhat of a hack and halfassed most of the car. So now I'm taking it apart to make it a driver again, when I discovered the floors had been repaired in the past. They didn't cut out the old rusted floor, they just welded new metal on top of it. It seems to be welded in ok, but really not the best way to repair a rusted out floor. My delema is do I cut the repair out and weld in new floors or do i just leave it as it is and get on with things. Looking for a bit of advise.

 

Whats it look like underneath? I would think if they just welded a new panel over a rusted out panel there is probably exposed holes on the underside where water and debris can get trapped and cause the new panel to rust out eventually?

 

There's an option that is easier, and will get it done, if the patches are welded in good and you want to save them. You can do some careful measuring to determine the edges of the patches, and then mark out the edge under the car on the old metal. After you've got things marked, take a cutoff wheel and cut a hole just through the old metal in the center of the patch. Then carefully open up the hole each direction until you've got all the old floor removed up to the welded patch.
After that you can grind and tap the edges of the old floor down, and seam seal them. That will get any old metal off that can trap moisture, and get the new exposed so you can paint, or undercoat it, so it's fixed properly.

 

Both you guys are right, the exposed holes will catch water and dirt and rust up the new panels. I was thinking exactly 197BB427 said, except I think I'm going to weld things up on the bottom side once I get the old stuff cut off. Thanks for the advice