I am going to try some POR-15. The company sells a 'six pack' with (3) 4 oz. cans of POR-15 and (3) 4 oz. cans of blackcote. This looks like the cheapest way to go. The problem (?) is that in this kit, the POR-15 only comes in gloss black. I was hoping to get it in grey so I would be sure to cover the POR-15 completely with the topcoat. If I but the POR-15 in grey like I want and the topcoat in gloss black, the price goes up significantly.

My question for those that have worked with this stuff is how hard is it to paint gloss black over gloss black and be sure that the POR-15 is covered?

What is the cheapest and most convenient combination / pack to get what I need?

John
NNY

 

Another question, Are you doing one or two coats of POR-15? Is it worth it to do a second coat?

John
NNY

 

I know from what I have used POR-15 for, that you do need to topcoat it because the regular stuff will dull when exposed to the elements, so yes, you will want the "blackcote" or other topcoat from them. as far as painting a black top coat over a black basecoat, not sure I have any suggestions, but I personally wouldn't be overly concerned.

I do agree that going with a "six pack" is a better way to go, especially if you going to be painting things in a couple sessions. Once you open a can it doesn't take long before it starts to harden, especially in humid weather.

 

I hear POR 15 and Rust Bullet are the same things, but I've done a lot of reading as I ready to do my car and cringe at the little rust bubbles coming up under the 10yr old paint on my 50.

I plan on using Rust Bullet instead of POR. I spent some time e-mailing them (both companies) and while they seem to both have a good reputation as rust preventers the Rust Bullet product is apparently more autmotive friendly. The POR people specifically told me that their product was not designed for more than spot protection and that it was not intended to be covered by an automotive paint. I think if you want a black trailer to be rust free POR's the way to go, but I'm going Rust Bullet myself and will be working with it over the winter. (Rust bullet does sell small packs like POR) They specifically told me that I could use their product as a base primer and either prime or paint over it.

A tip I picked up in my research was to use two self tapping sheet metal screws, one at the bottom edge and one in the lid. That way you can pour out however much POR or RB you need without excessive exposure to the air (which is what cures both products).

Best of luck!

 

I'll have to remember that, sounds like a realy slick trick

 

I've been using Chassis Saver paint, again, pretty much the same animal. YES, it's hard to paint the black over black. I'm getting ready to 2nd coat my topcoat on the frame, as I am sure I missed some spots, particularly on the bottom. However, the Chassis Saver says to "scuff" the paint. I used a 3M pad, to scuff, and it left it so that you could pretty easily see where you covered and where you didn't, on the first coat. You would have to scuff any of the rust encapsulation paints, even if they don't say to. It comes out way too slick for any adhesion. Unless, you paint the topcoat while the encapsulator is still tacky, then you don't need to.

As a suggestion, depending on what kind of paint you are using for topcoat, you could spray a very thin "guide coat" of like-paint. Mine is enamel, so I could take a gray or white, and just mist the whole thing with a rattle-can, then you could easily see what's covered and what's not.

As for going bad, I've had mine open probably 10 times, and have about 1/3 of the gallon left. And it's still as good as the day I opened it. You do a "float" on top - just a very thin coat of reducer - and keep it in the fridge. I've had mine in the fridge for about 5 months now, and I'll be using it today or tomorrow, to paint some more panels.

Great stuff, by the way...



R

 

I used POR-15 once. I tried brushing it on wearing latex gloves. It was a hot day and the airtight gloves made my hands sweat, so I took them off and kept going. The result was a few drops of paint on my hands and fingertips. After trying chemicals, abrasives, and everything else I could think of to clean my hands, I ended up just waiting for it to wear off. It took more than two months.

I later decided to take the parts I had painted with POR-15 back down to bare metal. Using a bead blasting cabinet was a waste of time. The sand bounced off like it was hitting rubber. I ended up using a die grinder with a carbide cutter.

Paint that's durable is one thing, but paint that you can't remove when you want to is something else.

Dave
Roadsters.com

 

Regardless, it's still a GOOD thing, if you want paint you can't take off...I am undercoating the entire inside of my cab, plus the places I've had to put patch panels in. Agreed, it doesn't come off easy, either the parts or the hands, but it does exactly what it's designed to do. I wouldn't do another frame without it...

R

 

That's exactly right and RB told me that very thing. Though they didn't say it explicitly they implied that probably the best approach would be to prime over the RB while the second coat of RB was tacky. Then you could paint over the primer just like any primer. But you could use the RB as your primer so long as you painted with it tacky or scuffed before painting.

 

Hadn't thought of that, although I knew I probably wouldn't be ready to prime, while still tacky. But, that would make a lot of sense...maybe the next one...



R

 

moisture in the air is what cures POR15. it will actually cure faster on a humid day. If you top coat it with anything other than their topcoat do it before it fully cures because as mentioned above you cannot scuff it once it cures to topcoat it with anything but their product.

 

You're right, it's the moisture that cures both POR and RB (and probably most similar products) but they both suggest using their product in a humidity window to allow it to cure properly.

So far as POR goes, they told me they wouldn't suggest top coating with anything other than their topcoat.

RB suggests scuffing, but I haven't worked with it to know how hard that will be. Guess I'll find out soon enough.

It's probably best, no matter what you use, to prime or top coat over it BEFORE it fully cures. BUT BUT BUT, make sure you can use your primer or top coat over the product you choose. They're all the same, so far as what they do, but they're all different so far as what they are, and the different chemical make ups mean that they each have different restrictions for what will work over top, scuffed, tacky, or not. IN SHORT>>>DO YOUR HOMEWORK!

 

actually, they are all pretty much the same. They all say they ARE different so you'll buy theirs, plus their add-ons. Basically, they are all the same. POR-15....they are the most adamant about using their stuff, which leads me to believe, that they are the most common of all of them. Experimentation has led me to believe they are all pretty much the same, so use common sense, and figure out what they all say in common, and use that. Just let regular paint, be your guide....PPG says if you use non-PPG, your paint will fail...same with DuPont, etc. But TranStar has a great line of primers, and works with the above. But only if you take the risk to try it...

If it quacks like a duck and swims like a duck...chances are, it's a DUCK!!

r

 

POR-15 sells a primer ( called Tie-coat ) that lets you spray just about any automotive paint over it even when it's fully cured.

 

That reminds me...I was first talking with them over a year ago when I thought I'd get around to this instead of moving when I did. They did say that they were working on a product to allow an automotive top coat. Apparently they weren't lying.

And you're right RC, a lot of companies are just trying to get you to spend money on all their products. Do you blame them? But there is some risk when you mix chemicals, and I'd hate to see a top coat go over a base and fish eye or worse. I still think each person has to do their homework. But, yeah, don't necessarily take everything they say at face value.