U-Por weld primer - zinc or copper?

[Gusb]

I've managed to find some #2 U-Pol weld primer but it's copper instead of zinc. I want corrosion protection for lap-welded seams, doesn't the zinc version make more sense? Also the POR15 MetalReady stuff I'm using on everything contains zinc, so it seems the U-Por zinc primer would be more compatible.

Any opinions on SEM weld-tru primer? I've just heard that U-Por is the best?

 

[Degnol]

I think the copper will give you equal or better corrosion protection compared to the zinc. Zinc is just less expensive. I use copper at about $30/can don't remember the brand.

Ed