what do you guys think about using por15 rust preventive as full body bare metal prep "substitute for epoxy primer" with por15 tie-coat painted over with DuPont or ppg they say that you can but has any one done this I have used por15 rust preventive before and it works great "as long as you use metal ready on the shiny metal" but how does the paint adhere to the tie-coat?

Thanks for any info

Richard

Why would you want to go with something against industry standards?

Go with the epoxy primer on the properly sanded bare metal. It's known to have better adhesion to bare metal than any other product.

I see you are new here. Do a search on "POR" and read up. You will find a wealth of information and lots of opinions from the pros as well as many people that have used it. You will learn a lot! I know I did.

Well here is a link to there molecular structure and from my experience as long as you have seasoned the surface the por15 is more adhesive then epoxy primer. And it sprays alot smoother then epoxy primer.
http://www.por15.com/molecular.asp

Not to say POR does not have some uses but don't believe their marketing hype.
Search and read the posts!
This one is a must read:
http://www.hotrodders.com/showthrea...3&highlight=POR

Here is the question for you:

If one of the big boys like PPG, DuPont, S-W or the like don't have a "POR" like product in their line up, WHY?

Any of these companies could buy the POR company with what they spend on coffee in the lobby of their main office. If there was a need for that product as a foundation for their multi billion dollar paint business they would buy POR, buy the product from POR and relabel it or they would simply duplicate POR and make their own.

They supply the paint products that keep the biggest truck, plane, and train fleets in service. They sell BILLIONS of dollars of paint to these fleets. They back all their product systems with BILLIONS of dollars in warantees. If they thought that POR could help do this, it would be a part of their systems.

There is a place for POR, (very few in my opinion, but that is "opinion") but replacing a good epoxy or urethane primer as the foundation for real automotive paint is not one of them (THAT is NOT opinion).

Brian

It seems everyone is looking for a quick way out. It drives me nuts (but thats ok... ixtlan, I'm just venting here a bit )

I don't really want to address the technical aspects of the idea because Brian has, and will do a much better job of that. I want to bring up the reasoning behind it. I am a firm believer in the "crap in, crap out" school of thought, and to me, the idea of leaving rust on my metal (and that can be the only reason you are posting this) definitely falls into the "crap" category, no matter what it's covered up with.

Taking such shortcuts and making compromises with your bodywork WILL come back to haunt you, and the end result will show it.

I can't think of a single builder that regularly shares on this forum that would ever consider NOT stripping the whole body down to shiny bare steel in this situation. The more you read threads on this subject (and I think it would do you well to do some searches) the more you will find that most are anal to an extreme about getting rid of every little spot of rust before priming.

We do argue about the means of achieving this, whether it be chemical dipping, media blasting or good old DA sander and elbow grease, but none of use argue that it must be done.

Why would you even consider coating your whole car in POR in the first place? If it is just laziness, then that is a root problem that will show up in your workmanship throughout the entire car, and I would advise you to find a different hobby, because this one is a HUGE amount of work, is not forgiving to such shortcuts at all, and consumes more time than you can imagine.

If the reason is $$$ then I do have some sympathy for you because I have the same problem but I never entertained the thought of not stripping my whole body down the bare metal and getting rid of all the rust before using a high quality epoxy primer.

It doesn't have to be expensive, I don't have a DA sander or a compressor (well, I just bought one... but I didn't up til now), so all the work you see in my project journal has been done by hand! No machine tools whatsoever, just a good heavy pair of work gloves, lots of sandpaper, and lots of phosphoric acid rust dissolver. It's very inexpensive and it will get the job done properly but it will take a lot of work, a lot of patience and a lot of hours (three months worth of weekends and counting).

If you can't afford chemical dipping, and I wouldn't recommend blasting, but if you can't afford that either, then it can be done very cheaply by hand.

If you don't have patience, don't like hard work, don't have time, and don't have money, then my friend, you are stuck... you are in the wrong hobby and will probably end up giving it up not far down the line anyway.

I hope I haven't been to harsh, but I think someone needs to paint a realistic picture for you. Ignorance definitely isn't bliss in this case.

Good luck though!

Rich

POR does indeed have a place, but not in an overall build or re-finish. The tie-coat just plain SUCKS. You only want to use POR in areas you can't acess completely for stripping to bare metal. While I too follow rlackey's thinking on the stuff of thorough prep, not every car heads into "icon" status. If I observed some surface rust in an inaccessable area of a car not going full boat to bare metal, I would use POR and it will work...FOREVER. I did POR aroud a buddy's conversion van windows in 1998, and saw the van last year. He keeps it outside at all times, just washes it occaisionally, and all the window repairs were still as good as new. Lazy? No. Just a perfect instance for where to use the stuff. The others are right tho, do it proper or just don't do it.

Well you cant really say they do not por15 is just moisture cured polyurethane
every brand makes urethane. but i think i well just use an epoxy primer whats a good brand for epoxy primer with nice high build primer surfacer?.

Thanks
Richard

well it has nothing to do with rust i do not have any left i have
changed both floors firewall extensions front and rear frames trunk floors inner and outer wheel housings and quarter panels. There is little to no rust on the car any more it has nothing to do with rust i just find it adheres better then epoxy primer
http://www.fordmuscle.com/phpBB/vie...40073&forum=2&4

http://www.fordmuscle.com/phpBB/vie...c=36672&forum=1

A lot of people on this forum have been using the epoxy from Southern Polyurethanes (SPI) and really like it.
www.southernpolyurethanes.com.

Roger

Ixtlan,

I apologize, I shouldn't just assume things like that.

You know whats funny though, it just wouldn't surprise me at all to find someone wanting to spray a whole car with POR-15 instead of dealing with rust properly.

Rich

I scoped out yer pics...you coulda used some POR while the qtr was off the car in the areas between the rocker, inner, outer, and door post. Once covered in you can pretty much forget rust from the inside out. As far as the outside, just skip it. The tie-coat is s#!t and will craze when the solvent from your surfacer hits it (experience). Epoxy, done. Do your inner qtrs and wheel housings, and if you haven' welded the stuff in yet use weld thru primer for added longevity. Good luck with your project.

Ya i used 3m weld thru primer on all of it

Don't loose any sleep over it but that weld thru primer was not the product to use. It has very poor adhesion and can't be painted over. Actually as little as I think about POR, that would have been a fine place to use it.

Richard, a "moisture cured polyuretane with tree sap in it is a FAR CRY from a modern chemically cured urethane automotive product.

Let's just say that they are in the same time zone as far as technology. There is NO product in the major paint lines that has the claims or instructions to apply right over rust. They honestly make NO product even remotely close to POR.

Brian