POR15 life

[adam912]

Hi folks,

I'm wondering what experience you all have with the effectiveness of POR15 in keeping the rust from coming back. It seems to be pretty universally liked and recommended. But down to brass tacks: How many years have you had it in there and has it kept the rust at bay?

I have a '66 that's been through the wars, but now I have it where I want it, and I want to keep driving it for a long time!

I ask because 15 years ago I used other recommended products--especially that stuff that claims to "convert" the rust and looks/smells like Elmer's glue. Tar based undercoat went over that (not a good choice--still gets sticky on hot days!). The last few weekends I've been removing all of that old stuff, only to find that the material itself held up well--it came off in big solid sheets, but underneath it was rusty as hell.

So what so you think, will POR15 do a better job?

thanks!
Adam912.Out.

'66 912, 494K miles, 2.2L Type 4 fun!

[912-2.8]

I'm in the same boat after tearing out my interior... After a LOT of reading and talking to folks the 'sure' way to a happy future (via the hive mind) seems to be remove the rust mechanically and use a quality epoxy primer. No if ands or buts.

I'll be using an ospho type product as an 'indicator' basically and wire brushing till clean followed by PPG DP40 epoxy. Yucky, but best results.

t

[adam912]

I would strongly suggest not setting your sights on epoxy paints, unless perhaps they are of the marine type and designed for good adhesion. Most epoxies are strong but stick very unreliably to smooth surfaces.

Some recommendations, based on my recent experience.
1) Be aware that after crawling around in the compact cockpit wire brushing, scraping, and generally making a mess, you WILL be sore the next day! Unless of course you are one of those circus performers that can fold up into a suitcase...

2) Before you close it all up, add insulation and carpet and the like, be absolutely sure that front and rear windows do not leak. Otherwise your work will be for naught. 5 years ago I went to the expense of having the local pro windshield shop reinstall the front and rear windows with new OEM gaskets after I painted the car, even though I'd done the remove/install myself many times. He used a modern sealant injected in the gap and guaranteed no leaks for a lifetime. Well, the owner leak tested the rear window last month after I brought the car back to the shop. It leaked an amazing amount of water all over my freshly POR-15'd rear deck. He informed me that the tech who did the work 5 years ago "forgot" to seal the top edge of the window/gasket interface...apparently it was a hassle to do so he blew it off. Newly sealed, the car does not leak at all now.

3) Why is fixing leaks so important? Water will find a way to wick UNDER the epoxy and rust rust rust. Your floors and deck will look perfect until the rust bubbles the epoxy. That's what I just went through. Bad words were expressed strongly. Epoxy is very strong but has really bad adhesion qualities! I really believe that POR-15 has much better adhesion than epoxy. Time will tell!

Good luck!
Adam912.Out.

[tomkirkcis]

I have used POR 15 over the years. It is a great product. Other products do not like to stick to POR 15, so prep to top coat is critical, if you do want to top coat.

[merbesfield]

I have a different opinion on POR15. I have used it on various parts and it is very brittle and chips easily. My problem may be related to not having enough "rust" for the POR to stick to. POR seems to be marketed as an end all for rust, I say no thanks. Blast it, prep it, shoot it with Epoxy primer. Do it once, do it right. Skip the POR.

PS I have used Zero Rust and it seems to be much more durable though I cannot speak to its rust fighting capabilities.

[Barwaut]

+1 on Merbesfield.

Last month I happened to clean the inside floor parts of my Targa. The PO did them in POR15, but I could peel the sheets of with my fingers.
Didn't seem to have bonded that well.
Ofcourse it has a lot to do with prep, but this stuff is made to penetrate and bond....

So, I would pass on POR15.

[chiroracer]

I have had great luck with por 15 as long as the directions are followed on prep re;NO moisture. after it is dry it can get wet.I like the satin black for spot repairs.The gloss colors take too long to dry imo.

[Fishcop]

Epoxy. There are very good quality direct to metal epoxy primers available for use. Ask a pro if they use POR15 for customer restorations...

[raspy2point2]

And when the car is all done; NEVER wash the car with a hose-- too much pressure. Keep it in the garage covered and when its dirty- sponge wash it out of a bucket of water. I take a rag and rinse it out on the car to wet it down.Chris