A seam on one of my vehicles where the two pieces of steel overlap. Factory filled the gaps you see with seam sealer and i wanna do some metal work n smooth them out. Just not sure what to spray in there before i weld it. Weld thru, rust mort, epoxy?
Sorry, I meant what panel is that?
Just so I know what it lines up with, what modifications could be done, would it look good with one thing or another...
But to answer your question, the weld primer is just that, a primer that can strike an arc if you need to weld it, its good for roset welds, just spraying it into the seam wont necessarily help any more than any other paint, UNLESS you are welding directly on top of it. Its not really heat resistant any more than anything else if say you are welding up close to it...
So you could blast out or sand out the inside of the seam the best you can, prep and paint it with whatever you feel comfortable with then hammer and dolly, grind and cut it until its flat, grind off the paint where you intend to weld where the two pieces meet and then paint that after metal finishing it.
But to answer your question about what is best to use, I'd say epoxy is the strongest, then the rust mort and then weld primer. But its all in the prep work of course and all of those will work just fine. You'll probably never know/see a difference unless you split the seam one day and look during another restoration on the car.
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