POR15 question

[jtrock26]

Can POR15 be painted over? Curious about under the fender wells, and on the roof. I read the instructions on a can, and it talks about top-coating where direct sunlight will hit it, but doesn't say anything about actually painting over it with automotive paint??

 

[Vitesse_6]

Its best to sand it so the paint will stick to it, Ive used POR15 and painted the top coat about 30-40 min after the last coat of POR15.
Good luck, POR15 is a SOB to sand

 

[sahelzer]

My Fj55 has about 3 gallons of POR15 on it. As mentioned above you can lightly sand the POR15 and topcoat and I have also heard of people shooting a light layer of top coat on the POR15 while still tacky so the final top coat can bind better.

The manufacturers of POR15 do make a top coat primer and I think it is the Sh!t. It is everything POR 15 is not (easy to spray thru a gun, sands well, and takes a top coat well).

It you don't top coat POR15 the sliver turns to Yellow and I am told it breaks down. Seen it turn yellow on some parts after about 30 days. Top coated fine afterwards.

 

[sahelzer]

I know mud likes photos so I hope this doesn't come off as a thread hijack just want to answer your question and hopefully save someone a headache and shorten the learning curve.

1st pic is of my upper and lower Pig Fenders painted in POR 15. These are a combo of silver and black POR 15. I mostly used silver but then bought some from a friend and it happend to be black. It applies the same and can be used interchangeably and/or mixed.

I did the whole POR 15 prep process. Marine clean, metal ready then POR15. It is a pain in the ass but the results are worth it. I brushed POR 15 on the inter fenders to get a thicker coat and then sprayed the outer surfaces for a smooth finish. I thinned the POR using the solvent to get it thru my gun. Bought a cheap Harbor Freight gun for the job.

Once dry I used the POR Primer to coat everything prior to paint. You can see the primer coated fenders in these second picture. The primer is a light blue and seems to work well for both light and dark topcoats. You can spray this on think and it sand out nice and smooth. After using can primer for years this was a nice change. Sprayed it on really heavy to fill minor scratches etc then block sanded smooth.

The third image is one of my fenders with the final topcoat.
Lots of work I know to just drag it thru the brush on the trail but at least the rust gremlins have been somewhat dealt with.

 

[LC_Hamma]

My Fj55 has about 3 gallons of POR15 on it.

Same here + about 5 tubes of POR15 Patch. I don't bother sanding over POR15, I do that before applying it. The only parts that are not POR'd are body panels that still had factory paint remaining after sanding. I use the Tie Coat Primer, after the POR15 has cured, in areas that will get an added layer of topcoat, such as the rollcage, cargo cage, bumpers, suspension links or other areas exposed to the sunlight. I use commonly found Rustoleum for all topcoating.