Alright Veeky Forums

Alright Veeky Forums
I'm currently gonna attempt to weld some rust holes on my car and would like any advice you guys might have. I'm doing it on a 92 miata and it's in the rear rocker panel and one behind the rear passenger wheel well. Bought some galvanized steel and bondo body filler. I was gonna plug weld but wanted any tips you might have. I'll post the areas I'm working on in the comments

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1. you don't want galvanized steel
2. cut all of that area out
3. spray the inside and backside of your patch pieces with weld through primer
4. clean the paint off and clean your patch piece well
5. fit it up, will need a few clamps for that awkward spot
6. weld it in
7. grind it
8. paint with self etch primer

What's the structural integrity for rust replacement welds? Assuming quality material welded in, of course.

>that cancer
Cut it all out, OP. It's the only way to be sure.

Now that I get a better look at the area, I would cut straight across above the rust, and either get/make a patch panel but preferably cut one out of another car. At the top I would use an undercut to make a backing for a butt weld, then do plug wells in the door frame , fender lip, and bottom

These days there are factory specs for the timing of plug welds depending on what method you are using, exact procedures for doing structural overlaps like on A pillars with multiple layers, they not only have it 100% as good as the car is new, they take steps to not accidentally make it too strong and compromise the areas that are designed to deform.

So, basically, everything is replaceable, without consequence? As long as you know what you're doing.

Not necessarily, most high strength steel and hydroformed steel frames cannot be heated, or if they can it's only to 800f or so, so if there is damage to the point they can't be pulled cold they can't be repaired, and you can't weld cracks in them. Some insurance companies wouldn't cover certain repairs as well, like a bent floor in a convertible.