Richard Cooper

I just removed the bottom trip piece from my 81 to prime and paint it. The trim piece is made from aluminum, I thought it was plastic. The bottom of the car that this piece is bolted to is steel, well I found my piecs of steel totally rusted and all wavy.
I just finished sanding it and coating it with primer to protect it from further rust. The trim piece comes off real easy, just a few screws so maybe its time to take a look! :lol:

BeaterShark

I'm not sure if what I'm about to say is true for all primer, but in general, primer will NOT protect it from rust. Primer is porus and will allow water to seep through.

Glenn's 67 BB Vert

POR -15 would have been a better choice i think Good stuff--Glenn :auto:

Brettmc

My brother, the bodyman-on-the-side, says that there is a waterproof primer. That's we're going to put on my truck at some point.

Brett :thumbs:

gerry72

You are substantially correct. Except for two-part epoxy primers like featherfill they are more than porous. They actually pull in moisture. Anything that comes from a rattle can, or any lacquer or enamel primers need to be immediately sealed over.

KenSny

You get a chemical reaction when you fasten aluminum and steel together so that they touch. That's why they NEVER use steel nails on house siding. In a few years the hole will be corroded.

c3vettelover

POR-15 would be a much better answer than primer, it will actaully adhere itself to the rust if pre-treated correctly. Regular primer will let moisture through. However primer sealer will not. Oddly enough my 78 had VERY dead paint and damaged clearcoat when I bought it :crazy: Needing to replace the urethane nose and rear I didn't want to paint the car yet soooo....it's currently done in 2 colors of primer sealer!!! With 3 coats of green pearl clear coat :D It was cheap, didn't take a great deal of work and should protect the car for the next couple of years! Looks MUCH better now!! :thumbs:

OkeeGuy

:iagree: ive had several truckers tell me the same thing...

Richard Cooper

Thanks, while I still have the trim off I will re-sand it and put POR-15 on it tomorrow. :seeya