Removing really heavy oxidation

[Pandora]

Okay,



The proverbial friend of a friend has a nice black late 60`s, early 70`s Riviera that has pretty badly oxidized paint on the horizontal surfaces. To my eyes, it looks like it`s still in good shape, at least it`s all there. But it is really porous and grainy. What is the best way to get this back to normal?



I have plenty of experience with a PC, but none with an orbital, which is what I assume would be the easiest choice for this. I`ve been debating getting an orbital, but I don`t want to learn on this guys car. So I was thinking of trying to get it as good as possible by hand. What products would you recommend? Is this where a more abrasive clay would be beneficial? I`ve also debated trying some of my trusty AIO on it, but I can`t imagine it would help to level the surface. Is there any point in an aggressive polish and a wool pad on the PC, or will hand work accomplish more?



I have only been detailing cars in relatively good shape, things that 3M SMR and Menzerna`s polishes have been able to remove imperfections in, at least those visible in a halogen light. This is the first time I`ll be attacking something that really looks like it should be repainted. Any help appreciated, please let me know if I can clarify anything. Thanks!



Ben

[Mantic6t9]

You may want to look into 1Z Ultra polish and follow it up with your Menzerna polishes. Why would you want to do this by hand if you have a PC?

[Pandora]

I was thinking this might be the time to give Einszett a shot. My thoughts on hand polishing versus the PC were mainly based on thinking that I could safely use a more aggresive polish by hand, but I may be way off base here. Like I said, I`ve really only used the PC to deal with very light swirls in the past, this will be my first shot at really using it to make a visible difference that even the commoners would notice! Thanks for the advice.



Ben

[2wheelsx2]

I would test a spot with a polishing pad and DACP, and if that doesn`t do it, go to a cutting pad and DACP. Then you would have to move up to Diamond Cut or Compound Power Cleaner.



But I have been very successful with DACP and a cutting pad on some really bad finishes.

[imported_Tony]

A pc is an obital. It is a great place to start and safer than by hand.

[togwt]

The article that helped me understand the PC process was titled

"Porter Cable for Beginners" on Roadfly.com



Hope this helps../

[chris0626]

Originally posted by MCoupeBen

The proverbial friend of a friend has a nice black late 60`s, early 70`s Riviera that has pretty badly oxidized paint on the horizontal surfaces. To my eyes, it looks like it`s still in good shape, at least it`s all there. But it is really porous and grainy.

MCoupeBen, I`ve just now noticed your question. Maybe my experience will help a little. I`m no professional. But encountered a similar problem on my `70 VW Karmann Ghia -- supposedly red, but actually a pinkish/tomato-soup color when I started, because it was so heavily oxidized. And this is a single-stage paint, so I had no concern about "burning-through" the clearcoat. Also, I began my project assuming a new paint job was required, so I felt I had NOTHING to lose. It was my car, so I was willing to take some risks; your situation may be different.




I have plenty of experience with a PC, but none with an orbital, which is what I assume would be the easiest choice for this. I`ve been debating getting an orbital, but I don`t want to learn on this guys car. So I was thinking of trying to get it as good as possible by hand.

Don`t even think about trying this by hand, IMHO. I used a PC. Probably a pro-buffer (I think they`re called DAs?) would have done the job faster and quicker. As other have noted, the PC is an orbital. No way you`ll do harm with a PC.




What products would you recommend? Is this where a more abrasive clay would be beneficial? Don`t bother with clay, IMHO. It`s way too gentle, if your situation is similar to mine.




I`ve also debated trying some of my trusty AIO on it, but I can`t imagine it would help to level the surface.

Having read Jngrbrdman`s "Behold the Power of AIO," I tried it on this VW. It didn`t do a thing. No doubt, I don`t have Jngr`s technique. But I gave up after just trying it on the roof; it didn`t touch the oxidation. At best, there was maybe a 3% improvement. But maybe you have more experience with AIO; check out his thread and see if it works for you.




Is there any point in an aggressive polish and a wool pad on the PC, or will hand work accomplish more?

Going with the "least-abrasive-product-first" principle, I started with 3M`s SMR. Did nothing. Moved to their FCRC; did next-to-nothing. So I tackled the whole car with 3M Heavy-Cut Rubbing Compound. I was amazed at how it removed the oxidation and brought an awesome shine back to this single-stage paint. Of course, the HeavyCut also left a gazillion fine scratches, so now it`s taking me a very long time to "step back down" through less-abrasive polishes.



BTW, I could not find any wool pads locally for my PC. So I did all this with a yellow foam pad. If I had it to do over again, I`d delay my polishing til I could order and receive a wool pad.



YMMV!

[Jngrbrdman]

I have always had really good luck with AIO and oxidation. Now, there is a fine line between oxidation and clear coat damage. What Lynn might have been up against was damage that couldn`t simply be "cleaned" off. Sometimes you really do need an abrasive like DACP to really `scrub` with.

[chris0626]

Yep, Jngr, the oxidation I was dealing with wasn`t just needing "cleaned off." It was deep, in the paint, requiring that I polish off part of the surface.



But I still keep looking at your "Behold the Power of AIO" thread and :bow ...

[imported_chr9s]

Originally posted by Jngrbrdman

...Now, there is a fine line between oxidation and clear coat damage.



Ah, very true. A lot of people mistake clear coat failure for oxidation.

[chris0626]

But if he`s dealing with a late 60s/early 70s car, isn`t that too early for clearcoat? :nixweiss

[Jngrbrdman]

Well, I`m no paint expert, but I don`t see why the same damage that happens to a clear coat (which I was under the impression was basicly just clear paint) couldn`t happen to the paint as well. It may not be clear coat failure, but something is going wrong with the paint on that car.

[Scottwax]

I`d start with DACP and work up from there if DACP isn`t strong enough. Definitely use a machine, pc or rotary. I`ve removed heavy oxidation by hand, but it is very tiring and time consuming.



You also should make sure it truly is oxidation you are dealing with and not laquer checking. It was more of a problem in the 80`s with GM cars, but the paint actually cracked. Lots of little tiny cracks. If you were a few feet away, the paint just looked faded, but when you got close, you could see it was cracked. If that is the case, only a repaint will correct it.

[Pandora]

Wow,



Thanks all, it`s great to have all of the responses. Lynn, it sounds like your experience was similar. I don`t think the paint is checked, it just looks like it`s pitted and oxidized, and thus really rough on the top surfaces. But feeling it and getting really close to it, it still seems that the base is sound. Of course it also appears to be the original single stage paint, so it may just be too little too late. But I think I`ll start with a wool pad and DACP and then try a compound if that doesn`t do the trick.



I might have taken some engineering classes, but I can`t for the life of me remember that my PC is an "orbital" and that the other is a "rotary". I think of orbits as revolutions, and my PC just sorta jiggles, no orbits. It must really take the whole random thing to heart!



I`ll be sure to snap some before pics and hopefully get some in -progress shots as well. Any tips for getting good pics of black paint with NO shine? I assume direct light and a fairly oblique angle, but I`ll give a few things a shot. Thanks again everyone, I appreciate having such a nice source for my detailing queries!



Ben

[Accumulator]

I`d like to throw out my $0.02 on this one. I currently have 3 single-stage cars in varying degrees of originality and condition.



First off, clarification of jargon: a "D/A" or Dual Action buffer *IS* a random orbital/PC/Cyclo. Just another name for it. The other breed of buffer/polisher is the ROTARY. MCoupeBen, I dunno if you`d want to start out learning a rotary on someone ELSE`S classic car. It COULD end in disaster.



I can`t recall if that vintage Riv will have lacquer or acrylic enamel. It`s NOT clearcoated, these paints are a very different animal from modern basecoat/clears.



A new (at least to me) idea I got from Mike Phillips (he has more single-stage paint restoration experience than all the rest of us combined) is to first PRE-TREAT the paint with Meg`s #7. As MCoupeBen noticed, the oxidized paint looks very POROUS, well, IT IS. These older paints are where the "feeding the paint" stuff comes from. I know what everyone`s gonna say: "BULL! You don`t FEED paint!" Yeah, it`s bull for modern clearcoats, but it`s gospel-truth for older paints. By "feeding" the paint with the sort of oils in #7 BEFORE polishing, you will end up REDUCING the amount of abrading that you need to do. The general idea is to do the following:



Wash the car and maybe clay it. Apply the #7 with a cotton pad. Let it set up for a while and wipe it off with a cotton towel, NOT MF (it won`t come off evenly or look nice). Apply ANOTHER coat of #7 (again with a terry pad) and let it set up overnight. Wipe it off once more, again, as best you can. THEN start your polishing.



The 1Z polishes should work well, given their "oily" nature. finishing up with a "heavy" wax, such as Meg`s #16 or Blitz would probably be a good idea too. It`ll hide the problems you DON`T get out. There WILL be some, so know when to quit and be willing to say "good enough".



You MIGHT encounter some "checking" and cracking, but as long as the paint is still sticking to the metal it`ll just be a (minor) cosmetic issue. I have cracked/checked paint on the XJS that`s been that way for a long time.