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Issues with POR15

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Ok, now I have some POR15 on order, then I talked to the people at POR15. They maintain that I MUST wash all the bare metal down with their phosphoric acid based wash or the POR 15 won't stick. Bummer. My car is up on jacks, in the garage, with no suspension underneath. It's not like I can just roll it out into the driveway to acid treat the metal. This is getting to be a circus. Any other suggestions out there for a different coating for my new floorboards? Anybody want to buy a TR6 cheap, at this point?
 
You can use POR15 Metal Ready and then sponge / wash it off without making a huge mess.

It isn't that hard to work with Bill.
 
As an FYI - the directions that come with POR15 paint indicates you can paint it directly on rusty metal. Their Metal Ready (wash) directions indicate that you have to use it before painting.

Metal Ready can be sprayed on, and it works quickly to dissolve any rust. Fun to watch fresh metal appear.

After it has been applied it needs to be rinsed off with water, like kind of freaked me out since it had just taken all the rust off, but evidently the acid will weaken the metal if it isn't rinse off and it will leave a film on the metal which will interfere with the POR15 paint.

Wear gloves!
 
Because of all the issues involving POR-15, including little to no UV protection and multiple processing steps, I went with Eastwood's Rust Encapsulater. Time will eventually tell how good this stuff works, but according to the independent experiment cited above, it should prove out to be good stuff.

At least it was easy to apply, and I didn't have to worry about anything other then getting rid of the loose rust. It is available both as a brush on and in rattle cans. /bcforum/images/%%GRAEMLIN_URL%%/cool.gif
 
I have a spray bottle of phosphoric acid solution that I purchased from home depot. Works quickly on modest surface rust. When redoing my frame I sandblasted in the backyard, then prepped with phosphoric acid solution, then primed with red-oxide primer then top coated with POR15 topcoat in chasis black. I'm very pleased with the results.
 
[/quote]
Whooo hoo! That is a first. [/quote]

Probably a better percentage than I have!! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

I used to use muriatic acid (old name for hydrochloric acid) which is used for commercial pickling of steel. I have mentioned it before and said I used toilet bowl cleaner which has hydrochloric acid as the main active ingredient.

It seems the main advantage of phosphoric acid (Navel Jelly) is the safety aspect. Although I have used both and prefer muriatic when generous flushing after use is possible. I feel the muriatic is quicker and easier to clean after. But that is only my opinion.
 
Tom,

I agree, while I used the phosphoric acid solution for surface rust issues I used muriatic acid when I restored my fuel tank. That stuff was amazing cleaning to bare metal in seconds.
 
I have only used metal prep ONCE...two years ago on a '55 Ford gas tank (outer shell). It was pretty nice and didn't have a rough surface to help the POR-15 to stick to.

All other times I've simply sanded, blasted or otherwise abraded the surface of new metal...or simply scraped away any loose rust before I coated the metal.

You must have the surface clean and oil/silicone free...
 
I have just wire-brushed rusty surfaces and applied POR-15 with great results. The shock towers on my LR Discovery were done two years ago, and they still look great.

Someone said to use gloves...good tip.
 
I have been using a phosphoric acid based solution I found at Advance Auto Stores called 'The Right Stuff'. On heavy rust I will brush it on letting it soak in, with multiple applications and then let it sit. I can then use a razor blade scraper and the now black flaky rust comes right off. Only a light sanding for follow up. Will also wipe it on lightly as a preservative for bare metal. The label says it is comparable to OSPHO, which I see for way more money.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] And put paper down.
Ask me how I know...[/QUOTE]

And plastic under the paper......ask me how I know...

I, like Mart, went with Eastwood, but I've yet to do mine. I had a bout with acid washing a frame in the past and plastic is a definite plus.
 
I'm not "totally" impressed with my frame-on POR 15 job, but about a month ago I finished applying it, just as the directions state.

Rubber gloves, mountains of newspaper, plenty of mess, laquer thinner handy.

Washing, rinsing, etc. took me about two weeks. Sounds nuts, but I work, so it was all in spare time, and the grease on a 40 year old car took forever to get off. The box frame has lots of hidden areas. I had dirt and muck everywhere and went through some old work clothes.

Anyway, I'd advise lots of patience, relax, do it slow.

The tough spots for me were near the engine and suspension areas.

I'm glad I did it, and I feel I protected the car, but I have some areas I know I'll touch up again someday.

Good luck. It is a great product. That much is clear.
 
POR is a lot of work. First a couple of points.

The POR-Chassis Black mentioned on the first page of this thread is NOT the same product used for rust conversion/protection... it is a top coat.

POR-15 is the rust coating product. You need to use the acid etch. Cleaning with acid and then POR coating bare metal is not a good idea. The phosphoric acid not only etches the bare metal to provide a rough surface for adhesion... the acid also leaves a phosphate coating which is beneficial for paint adhesion.

In similar situations to that mentioned at the start of this thread, I have put plastic sheeting on the floor and used the pump sprayers to mist coat the surface. Work the acid into tough rust using a wire brush. Above all else, keep the surface wet as long as possible to produce a uniform dark grey surface. Don't let it dry out and go "white" on you. When you're done, wash the panel down, then immediately towel it dry. The resulting very fine flash surface rust will not adversely affect POR.

I was recently tongue-lashed on another forum for using POR's Marine Clean (their recommended first step in preparation). I was told that Marine Clean leaves a residue behind that is tenacious, limits the effectiveness of the acid etch, and reduces POR's bond strength. Until POR tells me otherwise... this is hearsay. However, it wouldn't hurt to use a ScotchBrite pad to scrub the surface after using Marine Clean to remove any residue that it MIGHT leave prior to acid etching.

I have a love-hate relationship with POR.
 
I used POR15 on both my bugeye and my son's TR6. It is impossiple to apply to the underside with out wearing some of it for a week or two. But if it protects like it sticks to skin, its gotta be good.
 
All this talk of acid etching, excessive preparation, etc. is really confusing....

I hate to yell but YOU DON'T NEED ALL OF THIS EXTRA STUFF IF YOU ARE PAINTING OVER RUST!

If you are using POR-15 (regular OR chassis black) simply brush off any crusty or loose rust, make sure the surface is free from grease and oil and paint it on!

Chassis black is non-photo reactive so UV light WILL NOT affect it. It is the same formula as regular POR-15 (except for the UV additives and the satin finish)...it CAN be used as a top coat for regular POR-15 but it has the same rustproofing qualities as the regular stuff.

I used to sell this stuff years ago when there were protected territories and you could only buy it from a small number of dealers. I used to buy it from a distributor and resell it at swap meets.

The beauty of this product (and similar products) is the ease of application and the long lasting results. You should be able to paint the average bare TR frame in a couple of hours...just slap it on...it dries without brush marks to a great finish...so simple even I can get it right!
 
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