POR-15 Rust Preventative "paint"

   / POR-15 Rust Preventative "paint" #1  

FatTire

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Kubota L5740, Unimog 404 w/ snowblower, Deere 620i UTV, MX5100 (sold)
Does anyone have experience with POR-15? I'm considering cleaning up and coating an old blade on a snowcat and I want it to last. In general, the life of a snowcat blade is a little easier than a snowplow on a truck or tractor, shouldn't be running on the ground, fewer rocks, etc.

Is this stuff worth its considerable price? And if so, is their "metal prep" product a necessity?
 
   / POR-15 Rust Preventative "paint" #2  
I’ve used it. You have to get the metal clean and clear of rust, and it requires a topcoat of some other paint because it has no UV protection in it.
 
   / POR-15 Rust Preventative "paint" #3  
IMO...when it comes to painting with POR 15 or any other overcoating...preparation is everything...

POR 15 is a high quality product and performs as advertised...I only use on special project applications...
 
   / POR-15 Rust Preventative "paint" #5  
I used POR15 on my father's truck to cover rust that was forming on the frame. I did minimal prep but did wash, pressure wash and then wire brush the heavy rust off. I went over the original frame coating in most spots. This was about 2014 or so.

His truck plows snow and he is probably the hardest person on trucks in the world. The truck will plow all winter, get covered in road salt, and he will park it in the barn (with dirt floor) all summer to "keep the miles off". It never gets washed off. The truck is a 2011 with 40K miles, but beat within an inch of its life.

Currently the POR15 is peeling off in sheets and there is heavy scale behind it. Rockers look rough and I know I could find a hole in the frame if I look hard enough. Water will get behind it and rot from the backside. So its not infallible, but good surface prep will go a long way to making it work.
 
   / POR-15 Rust Preventative "paint" #6  
I've had good luck with the paints that chemically react with rust (Fe2O3) to form iron sulphide (FeS), which is black. One that's relatively easy to find is Rustoleum's Rust Reformer. Available at Lowes/Home Depot and probably most hardware stores. I used it once on a Gravely snow plow that had most of its paint rubbed off on the face side. Sprayed it, and absolutely never had any rust on it.

Wire brush any loose rust. That's about all you need to do.

You can paint over it, if you don't like the black color. Rustoleum has mixed some black primer in with the stuff; so, it's immediately black.

I've used 2 or 3 other brands in the past, a long way back. They've all worked well.

Ralph
 
   / POR-15 Rust Preventative "paint"
  • Thread Starter
#7  
Seems like either the Rust-Grip or the Rust Reformer would save some prep work. I have used something like Rust Reformer before but haven't painted over it.
 
   / POR-15 Rust Preventative "paint" #8  
I have used POR-15 on a set of EV battery trays/frame. It coats very nice and smooth, is hard as diamond, and seems to be holding up well. I believe that their "metal prep" is a ?%? solution of phosphoric acid that lightly etches any bare metal and neutralizes any rust. IMHO it is ESSENTIAL to make it perform properly.
 
   / POR-15 Rust Preventative "paint" #9  
POR-15 is just another miracle product that is marketed to "do it yourself" folks. POR is old technology - nothing new or propitiatory about it. POR brand is the most overpriced of them all.

What's wrong with POR-15?

1. If you want POR-15 to last, the parts to be painted must be be clean and rust-free (just like any other paint).
2. POR-15 does work, if parts are clean and rust free BUT, it is extremely brittle. It chips and peels if damaged.
3. Damaged areas hold moisture, which creates even more rust.
4. It is a cheap product that ISN'T cheap

If you are painting something that has significant value, and you're willing to take the time to do the prep work, then use epoxy primer!

There is a lot of folklore when it comes to paint. I'm just sharing info that is commonly known among restoration professionals that may not be as easy for the less experienced to figure out.
 
   / POR-15 Rust Preventative "paint" #10  
Used it on a flail mower after some of the sheet metal was replaced, I prepped everything with OSPHO and used a brush to apply. It held up well on some of the old metal but the but on the new it starting to flake off. Like others said if it is to be left in the sun you may want to use a top coat because it does fade. I think it works best on rusted areas that are well prepped. It is expensive and there are other cheaper products that would have done a better job for my application.
 
 
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