Seam Rust

[Foot Stomper]

When two panels are being welded together, it's imperative to use zinc or copper weld thru primer. These products will prevent rust better than anything else and are the easiest to weld. Most folks will put too much on, won't wait for it to dry or buy the cheapest product and use it once or twice and then refuse to use it again, then go back to welding bare steel because it welds far easier than steel coated with zinc or copper. These products will help to keep your spot welds smaller too but the main thing is they don't burn off leaving a large area of unprotected metal between the panels.

If you're butt welding, this product has zero purpose. It's only meant for welded overlap.