Is POR-15 any good ?

[CASCADEWILLY]

What has been your experience with POR15 products ?

Willy

 

[Deleted member 3577]

The chemist who came up with it was no doubt an LBC owner.

 

[smcmanus]

I bought some for a project. "Paint right over rust!" my arse. There are about 7 steps and 2 other chemicals applied before you "Paint right over rust!" Then it has to be topcoated with something else because it is not UV resistant! The other real problem I have is that once you expose the POR 15 to moisture, the entire contents of the can is shot. I bought a gallon and after reading all the literature, I returned it. If you are going to use it, buy the smallest container you need for the current use because once opened, there is no shelf life.

OK, I am impressed with their "Marine Clean" and gas tank sealer. I will continue to use it. I'm sure that the POR-15 is good, but it is much easier to use "Rustoleum rusty metal primer" and Rustoleum paint. Rustoleum has an indefinate shelf life, and the rusty metal primer clings to rust with vigor.

Have a nice day
Steve

 

[dklawson]

While I like POR-15, my comments closely echo those of smcmanus. To properly apply POR you need to devote a tremendous amount of time to preparation. They don't stress this point in their literature, but the stuff sticks MUCH better to rough, treated surfaces than sound metal. It's so glasslike that getting topcoats to stick is difficult. They sell a special primer for their products but I don't like it.

My experiences with the stuff prompted me to record what works and what doesnt. If you care to read my continued comments, download:
https://home.mindspring.com/~purlawson/files/POR-15%20dkl.pdf

I do still use the stuff but only on certain parts and locations. It does what they say it will do, it just isn't easy to apply. There are places where it's appropriate but don't be duped into thinking it's easy to work with. If you want to try it, buy their starter/evaluation kit which includes about a cup of POR, a brush, rubber gloves, and small bottles of the preparation chemicals. As smcmanus said, DON'T buy large containers of POR. It's available in "six-packs" of 8oz cans. That's the way to go for most of us.

I completely agree about their gas tank liner kit. I've used a couple of brands and like theirs the best.

 

[AlanT]

It's an amazing product. It sticks ten times better to what it is dripped upon than what you are actually trying to coat.

Alan T

 

[Richard Dickinson]

In the November 2003 "Auto Restorer Magazine" there was an article comparing Por-15 with Eastwood Rust Encapsulator. The author tested both products on a rusty hood. He divided it up into four sections and used a single coat and a double coat of each product following the instructions for each. He left it outside for four months and subjected it to a daily salt water spray. His conclusion was that the Eastwood product was superior both in results, application, and cost. I haven't used either product, but I have used Rustoleum. Don't know long term performance. It seems to work fine, but you need to let several days laps before you top coat it to prevent solvent pop.

 

[Skip & Lynne]

OK Call me stupid but WHY would anyone WANT to PAINT OVER RUST?

 

[Keoke]

[ QUOTE ]
OK Call me stupid but WHY would anyone WANT to PAINT OVER RUST?

[/ QUOTE ]

---------Cuz its UGLY----Keoke- /ubbthreads/images/graemlins/grin.gif

 

[Skip & Lynne]

like my mother in law

 

[Exotexs]

mother may be ugly but she gots the dough to help rebuild the Bentley.

Pork-15, I tried the stuff, forget it, too much trouble for nothin', doesn't stick to the metal even after I went through the steps 1 by 1 by the book. Mine is peeling off already, and I did leave the metal "shiny" as the instructions say. a waste of mother's money.

I had much better luck spraying Black Truck Bed Coating on parts that needed a cosmetic facelift. I liked it so much that I went and bought another can at O'Reilly's. It hides imperfections too. Nice satin finish, not gloss, not flat.

Just get a revolving sander and clean the part well, or take it to your local Chrome Shop and let them dip it in acid for a real cleaning, then spray a coat, let dry two or 3 days, spray another, until you run out.

Forget about Pork-15.

 

[Skip & Lynne]

here is what I don`t understand about this whole thing, if it is rusty and corroded why not sandblast or clean it properly and prime and paint it instead of just covering it up with something

 

[Editor_Reid]

[ QUOTE ]
here is what I don`t understand about this whole thing, if it is rusty and corroded why not sandblast or clean it properly and prime and paint it instead of just covering it up with something

[/ QUOTE ]

Hear, hear. I have never understood how there can even be a market for something that allows you to paint over rust -- the very idea of it is completely counter to the idea of "doing it right."

Using POR seems kind of like choosing to use an inch-thick layer of bondo instead of actually straightening wrinkled body panels. Or choosing to repair torn upholstery by covering the tear with duct tape. OK, the wrinkles in the body panel aren't visible, and neither is the upholstery tear, but does anyone really consider them "repaired"?

 

[dklawson]

For those who have never used POR....

Yes, POR stands for Paint Over Rust, but to be honest... you're not. The preparation steps involved require that the rust be chemically treated with phosphoric acid which removes most rust and converts what doesn't wash away to iron phosphate (leaving a matte grey surface).

The comment by Exotexs that the stuff won't stick to shiny metal is quite correct. I don't remember them encouraging you to leave any metal shiny though. The procedure I remember and follow is to sandblast smooth metal to roughen it and to follow that with the acid etching to activate the surface. As you can see, this isn't' really "painting over rust".

I have used Rust Encapsulator (however, I sometimes still use its older name, Coroless). It is indeed a much easier to work with product. It's also "moderately sandable" and compatible with top coat primers. You still want to remove as much rust as possible when using it, but the preparation is easier and results more predictable.

Neither product is as simple as just painting. As mentioned in comments above, you want to remove as much rust as possible and use these products where you can't reasonably get to or where you anticipate the need for long term protection against rust from potentially trapped water.

 

[Exotexs]

yes but the way they sell the stuff is like you just apply it over the rust, and you live happily ever after, until you get the kit and realize you could have sandblasted it faster and cheaper and painted it with most anything else, including Rust Oleum. I painted the under-bumper panel with the Black Truck Bed Coating in one Jaguar. I painted the under-bumper panel with POR-15 in the other Jaguar. Guess which one has not peeled off? Once bitten, twice shy.

 

[CASCADEWILLY]

Does anyone thin it and spray it or are they brushing it on ?

 

[Richard Dickinson]

Someone asked why would you want to paint over rust? The simple answer is that you don't. However, sometimes even with blasting and sanding you can't be assured of getting all of the rust out of pits and complicated shapes. So why not use a rust converter primer to make sure rust dosen't eventually pop through? Particularly on suspension parts where you can't use an acid type rust remover.

 

[dklawson]

I have thinned and sprayed POR. The preparation comments above still apply. You get out what you put into the preparation.

For spraying,use ONLY their solvent. DO NOT use anything else. I use a cheap, single action air brush, it works VERY well. Clean with cheap lacquer thinner if you feel it's worth it. I wouldn't use POR in a quality spray gun.

 

[Exotexs]

then why do they call it Paint-Over-Rust??? Nothing could be further away from the truth. It takes so much time to prepare parts to be coated with POR-15, you do better and certainly FASTER just getting the part sandblasted, then using any primer and paint of your choice. Not to mention cheaper. My advice? just pass on POR-15. Been there done that.

 

[John Loftus]

Agree. I sand blast parts and if there is some concern with residual rust (such as hard to get into seams) then I use Zero-Rust primer. Came highly recommended and they have test to back it up.
https://www.zerorust.com/

Cheers,
John

 

[dklawson]

I don't think any of us disagree about POR being more difficult to apply than their literature suggests and I don't think any who have used it would put it on top of easily removed rust.

Why use POR-15? There is one situation where POR excels. Applied to properly roughened and treated steel, POR is nearly impossible to remove. That makes it an excellent base coat to use on frame and suspension components that are exposed to impact from road debris. I still top coat such parts with Eastwood Chassis Black for UV protection and a satin appearance, but POR's impact resistance makes it a great choice for these components. Some will say to this "Powder Coat" or "Hammerite Paint" it, while both give great finishes, neither is as chip resistant as POR.