Paint: Por 15

[HawkBuilder]

I'm having a Mustang II front end stubbed onto a 62 Champ frame. The shop doing it sandblasted the frame first. When I get it back I was planning on coating the frame with POR 15, which I've never used before. Here's my question: if the frame comes back with a new sheen of rust on that bare metal, which I strongly suspect it will, can I apply the POR 15 right on it? In other words, is it like some of the rust converter products I've used before where you can put it right on a rusty surface? Again, I'm not expecting a heavy coat of new rust, but I will bet it will have a thin coat all over.

[1badstude]

Yes but follow the directions and use all the products such as the wash.and the metal prep, the name por stands for paint over rust . And take special precautions to protect your self and you surroundings as it don't come back off easily if at all and you will be wearing it for awhile.

[sweetolbob]

On steel with minimal rust, I'd prefer to use epoxy primer and topcoat with paint. If the rust is significant then POR15 should work. I used POR15 on a trailer I built from mild steel with minimal rust prior to coating and it came off a year later in sheets even though I cleaned it with solvent prior to painting.

Better safe than sorry, use primer and paint. Bob

[Bradford]

Look up KBS Coatings. They have a system that works great and has an inhibitor that you can spray on bare metal and it wont rust for a long time even with no paint on it.
The paint is pretty nasty so wear gloves and cover the floor. You brush it on and it levels out pretty good as if you sprayed it.

[1badstude]

When the economy went bad my lark sat outside next to my garage por 15 with a inch of its life for 5 yrs no rust or pealing.

[kwoodyh]

Finally something on the SDC Forum I know about. As a former POR 15 seller I highly recommend using it just follow the instructions (as with any coating) and remember it is UV sensitive if not top coated, spraying it on works well but be sure to use a cheap gun. The engine paint is awesome but I'm not sure if they offer a Studebaker color?

[Mrs K Corbin]

Brush, don't spray. I've done both and the spray didn't hold. Pay attention to the humidity in the air as well. Follow the directions.....

[kwoodyh]

Heck you could even roll it on, the paint has excellent self leveling properties and as Mrs. Corbin said Follow the directions!

[wdills]

The sandblasted surface will have enough tooth for the POR-15 to stick. Flash rust that may appear on the blasted part will not affect how the POR sticks.

However, I agree with Bob. If you have a nice clean sandblasted surface just spray it with a good quality black epoxy primer. During the course of my restoration I had several occasions where I didn't like the finish on a part and I would sandblast my fresh epoxy or POR-15 back off and re-apply it. The POR-15 would sandblast off very easily. On the other hand the epoxy was very difficult to get off. In some cases the epoxy coated parts had to go back to the blast cabinet 2 or 3 times before we got all the little spots off. In my limited experience, epoxy sticks much better and provides a more durable surface. The SPI epoxy also dries to a very nice low sheen finish that closely matches factory frame paint. The POR-15 I applied was too shiny for my liking.

[BRUCESTUDE]

I've used POR15 semi-gloss black on the suspension parts of 2 different Studes. Both times I had the parts cleaned at a local machine shop, I then wiped with prep-sol, and brushed on POR15. The parts looked great and have held up well!

[jbwhttail]

My 56J has POR15 on engine ans suspension, the car has been finished since 2007 and the only touch up I have done is to the intake manifold center ports. That is from exhaust heat. As others have said follow the directions. Brush it on no need to spray. One other thing, be sure to wear gloves with the metal prep, yellow skin and peeling if not, from experience!

[what huh]

not to change the subject but any chance of getting some pictures of the frame with the mustang goodies welded in place?

Been on my mind recently about doing it

[wittsend]

The concept of POR 15 is that it is intended to rely upon the coarse texture of the rust to adhere. In some regards it is similar to Tool Dip. I often equate the cured coating to the surface of a Super Ball. It is like a very hard rubber. It flexes to a point, but will crack and chunk if flexed too far. And this is more likely to happen the thicker the coating. While the coating itself may be "scuff" tough, adhesion can be an issue. Anything that can bite into the coating and then peel it is a cause for concern. As an example if you drag a clean shoe across it repeatedly it will hold up well. If you have dirt or metal embedded into the shoe it will likely tear into the surface and possibly peel. The smoother the original metal texture the more likely the peeling is to occur. Sand blasting helps, but a wire brush burnishes the metal and closes the pores. The surface needs to be completely free of oil. Their Marine Clean is basically an alkaline, caustic cleaner. Their metal prep is phosphoric acid. So, you don't need their stuff, but the process still needs to be done. By the way if the coating isn't onto raw metal they themselves say it isn't effective. So you basically need to strip any paint on surfaces you want to protect.

The coating process can be difficult because there is a "window" where you can apply the second coat (and you really need a second coat if brushing). Too soon and the first coat does not cure properly. Too late and you have adhesion problems. POR-15 is moisture cured so humidity plays its roll significantly. I have HAD to re-coat in close to an hour when the humidity is high and also had to WAIT about 10 hours when it is low. This can cause mid-night applications you don't necessarily plan for. The fumes aren't healthy for you and getting the stuff off of yourself is very difficult.

So, POR 15 really needs an ideal situation to work best. It is kind of a lazy man's way of treating rust. And those who are diligent to remove as much as possible (like I have) are only defeating the ability to adhere well. It doesn't mean that it still isn't useful regardless of their instructions. I often use it on the bottom of door interiors because I feel that it extremely helpful to prevent corrosion from the inside out. And in this area it is not susceptible to abrasion. Hard to reach chassis areas are also good for POR applications. Both these areas are not subject to UV rays. As others have mention I'd probably use a good automotive paint on a "clean" frame. I think you would get better adhesion and you would not need to top coat it to protect from UV rays. And, that top coating..., it also applies to their "window" of application. So, you have two POR-15 applications and a third (maybe fourth) top coat. You might have to be up 24 hours + to get the coatings timed properly.

I've used about 5 gallons of POR-15 on numerous cars. I love it, - and I hate it.

[colt45sa]

Brush, don't spray. I've done both and the spray didn't hold. Pay attention to the humidity in the air as well. Follow the directions.....

In 1991 I met a fellow who had sprayed POR-15 without a mask. He spent quite a bit of time in the hospital thereafter as the moisture cured urethane found the moisture in his lungs and cured there. He was eventually released but will suffer form the effects for the rest of his life. Brushing it on if o.k., spraying it is dangerous and extra care must be taken to assure that you don't inhale any of it.

[Mrs K Corbin]

I wasn't the one that sprayed it thank GOD....
I did brush it and will be the first to tell you, if you get it on you, you wear it for at least a week!