I'm getting ready to brush coat some chassis parts with POR-15. The instructions call for "special POR-15" thinner. Is it really a special thinner or will lacquer thinner/enamel reducer work for thinning and clean-up?
I POR'd my entire chassis (was a brand new from Fatman Fab) along with other piece parts. Once it started flaking off - following their directions to a T, and using all their stuff, I decided to do something different. I sandblasted my frame - POR came off in sheets, stamp size and bigger - and went with eastwood stuff. But back to the question at hand, I used reqular laquer thinner to clean brushes and guns, but i also used cheapie brushes and guns incase it didnt work.
YES you must use there thinnere . I use Chassie Saver this stuff works a lot better and you can coat both sides of a pannel with POR you are only to do one side
I just used it right out of the can without thinner. I went over the frame with a wire cup brush real quick and painted right over that. I can hit it with a sledge and the paint won't budge.
OK not trying to hi-jack this thread but guys help me out here because I see these posts a lot and I dont understand it. I thought the whole point of POR15 and the Eastwood equivalent was to stabilize the surface of metal that has already started to rust? Why are people using a rust stabilizer paint on new metal surfaces that are unrusted? I am not a chemist but thought the paint was designed to interact with the rusted surface to form a stabilized form of the steel (iron phosphote or whatever). Eastwood sells a chassis enamel that I figure it more appropriate for a newly build frame?
Theres at least a hundred ways to do a job ,but only one right way . Por 15 is worthless except on new metal rust never sleeps .
I always use it straight out of the can. For clean up, I have used lacquer thinner and mineral spirits. Both cut is satisfactorily for clean up.
The only time I had a problem with POR-15 was on new metal, thats when it would just pull up and flake off in chunks. Rusty pitted metal it sticks like glue.
Por15 won't stick a slick new surface. It likes rough nasty surfaces. If your going to thin it, use their stuff. why risk having to do it all over again to save a few dollars now?
I cleaned my Brookville frame (it had light rust from several years of GA humudity in an unheated garage before I got it) with Purple Power, used a locally available etch (they're all phosphoric acid). Then I sprayed with POR base coat, using their thinner, then a POR prmer, then a high fill primer on the exposed frame surfaces (high boy), then a wet sand and then the POR gloss Black Cote top coat, all these thinned with their thinner. Biggest problem I had was getting a balance of wet enough to laydown with no orange peel and not so wet it ran or sagged. So far so good, but the car hasn't quite been completed yet. However I haven't seen any evidence of faking or chipping when bumped. Dave
I sand blasted my '32 front axle etch primered it and Por-15 coated. Assembled the car and took it in for alignment. We had to chain the axle to the chassis plate and jack the two ends to correct the camber. The Por-15 didn't chip or flake off where the chain was wrapped around the axle. I wire brushed and wiped off my Columbia axle with lacquer thinner and brushed on the Por-15 on the bare rusted surface. After two years still no lifting or chips. The paint is harder than powder coating and more resistent to chemicals. I've had no negative issues with Por-15. The FOGGER
Just remember like the other guys said,it is designed to stick to rusty metal.If the metal is new or smooth,it will not work.And it says not to put a rust converter on first as it won't stick to that well either because it makes its own rust converter.
POR-15 has worked well for me on sandblasted metal that was previously rusty and pitted. I've had no adhesion problems, and any rust that may have lain hidden in pits or seams has not come back. The stuff requires specific preparation steps along with specific temperature and humidity conditions during application, and a second coat. Properly applied it really gets a grip and is very hard to remove. It nicely levels pitted surfaces. I only use it when there are pits or seams where bits of rust can hide in previously rusted parts. I don't use it on never-rusted clean metal. POR-15 requires moisture to cure. My theory is that it pulls moisture out of any buried rust during the curing process, so there is nothing left underneath the primer for rust to feed on.
Yeah, I used all their marine clean and metal prep before hand. I think may have had better luck if I woulda let the whole thing 'flash' rust for the afternoon (hot n' humid middle of july when i did it). When I had the frame re-blasted, the stuff honestly came off in sheets. The re-used his blasting sand and 3x5 chunks in some shovel scoops.
What isn't clear in your post is whether the frame was sanbblasted before applying the POR15 the first time. Was the metal of the frame slick new metal or roughened up by sand blasting or sanding or scuffing? Dave
Im in the restoration business since 1987 and never used por 15 . That said every single car thats come through my shop that has had a previous make over ten years or older have had por 15 and was always lifting ,its odd that no car was done by the same person .the up side is that i just make more money . as another post mentioned that blasting even had a lifting issue ,remember that silicone is embeded in the metal, sand as in all medias have silicone so wash all parts .i test my bare metals with a paint gun loaded with slow thinner and wash till the thinner runs clean . also whats wrong with just removing the rust just a thought.
So say for example I had a underside of a hood or inside of a fender that has heavy surface rust. just clean it, degrease it and brush on the POR 15 and your good to go? you can still top coat the POR 15 if you want a different color too right? Thanks J
I guess this would probably be the best solution to blast everything up and use a good paint! ? just more work, but sounds like it would last longer...
I just recently saw a couple jobs that I did where I applied POR-15, what 20 years ago?, and it is still doing what it was advertized to do-converting rust into a non-permeable, rock hard, inert material-it DOES require a certain amount of "tooth" to hang on to, and it does convert rust. I used it in my resto business for years, just followed directions and I never had a problem with it...I did see a trailer once that was painted with the clear POR-15, and it all fell off-the reason? My guess is, no rust-it was all new bare steel...wiped down with thinner, and sprayed on...they would have done better with etching primer on bare steel, then top coat...and if I recall, POR-15 sells what's called a "tie coat", that should be applied to it before top coating...In my opinion, it's good stuff, but I wouldn't mix in other chemicals, like thinner, just to save a few bucks...
I used POR on a 40 Ford chassis 14 years ago. Still strong. If it flakes off it is because new metal no "tooth". You need to rough it up or use a metal etch or D-A the metal before applying.
I use it all the time...since the late 70's, I think. You have to do it right, clean, degreased, and not any trace of water on the parts. I've used it on sandblasted parts, and on rusty metal, as long as you prep it correctly, you've got a great tough coating. I've sprayed it, as well, the only time I use their thinner. Lacquer thinner cleans it up very well afterward, as does acetone. The reason I use it on 'blasted frames, and such, is that it offers a moisture and oxygen blocking coating that is unmatched by regular paints. If it's painted on right, it's tough to sandblast it off!
I haven't used it yet but have spoken to a few different people at the POR stands at the different car shows I have attended . They all told me the same thing by telling me " To Follow THEIR Instructions to the "T" and to use THEIR PRODUCTS " . Make sure the metal is clean of all grease and to have the metal scuffed up like I was going to be putting some body filler on the metal . They told me the POR won't work good on new , smooth metal . It like rusty , pitted , scratched up metal the best ! When I do my frame I am using a grinder and a DA sander with 40g - 80g to let the POR have something to stick to .
I bought an off topic truck from texas. No rust on chassis. it was my daily and the first winter, the whole frame surface rusted. Put straight por 15 out of the can on it (after knocking the loose stuff off the frame) and it held up perfect for the 6 years I had the truck. The only place it didn't stick was the after market parts I put on for the lift kit.
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