por-15 frame prep question.

I finally finished ridding my frame of farm dirt, undercoat, mung, tar, grease, wasp nests and other undesirables. I used the metal prep over the whole frame and I'm ready to paint. But the metal prep white residue keeps coming back and I've power washed it twice. Do I have to get rid of it, or just paint over it?

Rick

 

I used POR15 on the frame and bottom side of the floor/trunk, etc. on my Galaxie.
When I applied it, I did brush over some of the white residue (metal prep reaction) that you are referring to. It seems like the instructions said it was ok to do that, but it's been four years and I could be wrong.

The POR15 has stuck very well to the under-side of my car. It's been through alot of rain, daily driving, and on the salt flats. Still looks good after all of that.



Malcolm

 

Been less than a year since I did the frame of my Brookville version of an A-V8 hiboy roadster. The rust I had was the result of a previous owner's loss of interest and consequent residence in a non temp controlled carport in middle GA humidity. IOW, lots of not so deep, but copius amounts of surface rust all over the frame.
After a treatment with a locally obtained metal prep solution called "Os-Pho". I then scuffed off any powdery residue, wiped down one last time, and sprayed with POR15 base coat, then self etching POR primer, and next a sandable filler/primer, a wet sand then POR 15 Top Coat. That damn Top Coat, or whatever similar it is they call it, is the hardest paint I ever tried to apply and reach a balance between orange peel from dry coat application and consequent orange peel versus a too wet coat that looked damn good till it all of a sudden sagged! But yeah, scuff it off with Scotch Brite, wipe it down and paint it!
Dave

 

I skipped the metal prep and went right to POR-15 on my 40. That was about 15 years ago and its still lookin great.

 

? I takeit to mean it was "clean" - but no sanding? no primer? Thank you.

 

All right I'm painting over it. Never actually done anything like this before, normally this would be 100 dollars I could've spent of motor. Thanks for the input.

 

Just a reminder, protect all your exposed skin. Por-15 sticks to skin as well as metal. Wear safety goggles too. Rubber gloves and long sleeves. The FOGGER

 

It was a frame on build in my parents driveway, so I was a bit limited. I cleaned it off, wire brushed the scale off it, skipped the metal prep and went right to POR-15.

 

POR-15 over a really clean sandblasted frame seems to not do as well as if it is applied over a bit of....let's say, imperfect surface. At least this is the case with a 35 frame a friend recently painted in my shop. Although, it seems to work great either way. Also, he used no Op-Pho, no metal cleaners of any sort. Looks darn good.

 

i dont trust por anymore. we only use KBS in our shop now. in my opinion, kbs is what por was 6 years ago. just one mans opinion though. good luck on ur project!

 

Huh... for some reason, I thought Por-15 was owned by KBS Coatings.

This website says otherwise, but the name of the site itself sure can confuse a guy!
http://www.por15store.com/

Same site, different name:
http://www.kbs-coatings.com/

 

NOW you tell me! ARRRGGGH! If anyone's looking for me, I'll be in the garage with gas and a wire brush.

 

Not enough gas or wire brushes in the world. It will come off when its darn well ready!

 

I've seen this debate before... seems KBS is a disgruntled former POR-15 dealer... now selling another competing product.

Same deal with Rust-Bullet IIRC....

I've used POR-15 for 15 years and I'm happy with it.

 

If you use the por thinner it will take the por15 off your skin.

 

POR 15 is made to paint over rust. Paint Over Rust. I didn't use any metal prep on mine. wire wheeled it pretty good and brushed it on.

doesn't like grease at all. found that out on some spots I missed.