I have absolutely no experience with this stuff but from everything I read it's what I will want to use on things like my floor pans, inner rear quarter panels, and such. Everyplace I see that sells it also includes some of those foam brushes to apply it with. What I am wondering is can this stuff be sprayed like a regular primer or paint? If it can't, is it self leveling so that there won't be brush marks in it? Everywhere I plan to use it will pretty much be covered and out of site but I am kind of obsessive about things like that. If I know it's there, it will drive me nuts whether I can see it or not.

 

You can indeed reduce it and spray it...not sure of the ratio...

It is also self leveling. I applied it with a generic pant brush and it looks like it was sprayed on...I went with brushing vs panting to reduce the risk of over-spray. It sticks really really well so if you do spray you have to mask 100% certain that over spray will be eliminated.

-Gun

 

Don't bother with those little foam brushes. Buy some cheap brush packs from the local Dollar Store and use those for areas you want to use a brush for. For example I brushed the inside of the front and rear bumpers (after proper prep) with 2 coats. Same as the inside of the fenders. These are cheap brushes and are exactly what you want as once you use the brush you'll have to toss it. I bought 4-pack variety packs (1/2", 3/4", 1" and 1 1/2" brushes) for a buck each and likely bought 10 or so packs.

Don't bother thinning it out. Using an HVLP spray gun we shot 3 coats unthinned on the underchassis, inside floor, trunk, roof engine bay, etc. never used any thinner and we had no problems with the spray or it gumming up the gun. make sure you clean the gun quickly once finished! Regular laquor thinner works well for cleaning the gun, any spills. Reducer works great to clean off any over spray while spraying or shortly afterwards.

It is self leveling and goes on very nicely. Keep in mind though that it isn't UV protected so after a while the sunlight can cause it to gray slightly. Top coat or use a good undercoating over it. I used a water based undercoating product from Second Skin called Spectrium over most of the POR-15. I didn't bother scuffing the POR beforehand and its on very well. It you paint over it you should use 220/240 grit sandpaper and lightly degloss the finish of the POR. Good 2-part Epoxy Primer bonds to it very well.. I don't recommend any other primer.

Tips
Don't dip the brush into the can! It'll harden the remaining contents quickly. Use a small scoop to scoop out what you need into a small container. A little goes a long way.. its like water really.
Use plastic wrap between the top of the can and the lid. I doubled it up and lightly tapped the lid on.
Read up on the instructions and remember.. the prep is the most important part!


If you are adding an undercoating..
Regarding the SS Spectrium undercoating.. I bought a 5gal pale of it and sprayed it 4mm thick over the POR on the underchassis and 2mm to 3mm thick over the POR on the interior floor pans and firewall. It is super easy to cleanup and cures nicely. Its added protection and helps insulate the cabin from road noise. I applied their Damplifier Pro sound mats onto the POR and the spectrium over top that on the interior floor pans. Something to think about if you haven't already. Check out the underchassis pic in the ROTM link in my sig to see how it looks.

Hope this helps.

 

You can spray it direct from the can from what I have read or you can thin it with POR15 Solvent for a thinner coat (don't know if you can use any other solvents). I read on the can that you can spray it at 30-35 PSI for a gloss coating or at 20-25 PSI for a slightly flatter finish.
You should also not use any rust converters under it as it will affect how it sticks (darn, I had not read that before now.) I have read on other forums that people have had excellent results with rust converters before use, but POR 15 is actually a rust converter itself. You can use Metal Ready (phosphoric acid) to remove rust under it. It says it is perfect for coating directly over rust, seasoned or sandblasted metals. Smooth clean metal must be roughed up or treated with metal Ready to give it a tooth to stick too.
It is also UV sensitive. Meaning it should be top-coated with POR15 paint or any other paint to block sunlight... perfect for hidden areas that won't get sunlight (no topcoat needed).
I have spent the past 4 days stripping and prepping my windshield and backlight bays for a coat. It's a lot more work than I thought removing 7 layers of paint and primer, but it hid a lot of minor that could have caused some serious problems in a couple years.
I found rust in all four corners of both windows and in quite a few of the spot welds where water just collected. Also had some rust inside, under the roof, on the support rails at both windows (under the headliner, where water got trapped once it leaked in.) Nothing Major, but I am going to grind/sand to the bare metal and spray POR15 over the entire interior roof. Areas I can't sand in the ceiling and also lay a strip of it before I put the seam sealer back in my drip rails to seal out all moisture and prevent any rust from doing any further damage.
I will probably also do my door interiors, under the rear seat, walls, under dash/firewall and floor (once I put a new one in). Basically all the interior sheet metal that is hidden that could trap water and possibly rust without my knowledge.
One last thing I know about it (haven't tried it yet)... Once it is dry, no solvent or paint stripper can remove it. So be sure to clean any over-spray or drips before they have a chance to dry! Once it is on, It's on!
Good Luck and be sure to post your results!

 

Excellent advice from Adrenolin! This stuff is not like ordinary paint. If you get some in the lip of the can and then put the lid back on over it you may never get the can open again.
It does not come off of your skin either. Well, it will, but it takes some real scrubbing and time.

 

Thanks, guys! That is exactly the information I was looking for! It'll be a while before I am ready to use it but I want to be prepared. I am still gutting the car for complete rotisserie media blasting. Almost there, though. Got all the removable body panels, doors, windows, trim, and interior stripped off it. Just need to get the drivetrain, suspension, brakes system, and remaining wiring out of it and it'll be ready. I'll be posting pictures as things progress.

 

use a turkey baster to get the paint out of the can and saran wrap inbetween the lid and can if you get it on the seal

 

Good tip. Thanks.

 

yeah man.. we did my brothers entire 69 cougar in the stuff

 

Here in PA it is starting to get colder and we don't have a heated garage to work in.

Can someone with POR15 please look and see what the working temps are for me please?

I want to get the little starter kit that covers about 12 SQ feet from MU and just do a few things that need to be taken care of now and I'll hit it hard in the spring for the rest of the body.

Thanks,
Lynn