Paint Preparation

We have talked about bodywork and painting but I have a question about metal preparation. I have a car in several years of primer. Although well protected, some places where there had been stone nicks, have started to show very light surface rust. The original paint was chemically striped and I had applied a metal prep (I think Metal Prep 76 produced by Al-Chem) and a zinc phosphate solution by the same company. Anyways for my question. Working in sections I have sanded the old primer off and I am down to bare metal on the back third of the car. I am looking for a product that will protect this metal while I continue with the rest of the primer removal, bodywork, filling, etc. until I can get a moisture proof primer applied. I would like a product which can be applied by hand and does not have to be rinsed off with water. I would like this product to convert any surface rust left after my sanding to something that will not continue to work on the metal under the paint. I saw a Bill Hirsch product called "Miracle Rust Remover and Metal Prep". This seems to be a product I could use but I get a litle nervous when I see the word "Miracle" (I've already had too many miracles!). Has anyone used this product and would they care to comment? What are some other options or products I could use? - Regards; Andy Leavitt 56 XK140 DHC, 67 XKE OTS

You are justified in being nervous when you see the word "Miracle" in any automotive product. Usually it is a miracle if they work as advertised. However, I have an open mind, and I'd like to know if and how this Miracle Rust Remover and Metal Prep works. I am a firm believer in the rule that there are no shortcuts in a quality paint job. I start by cleaning the bare metal with a commercial metal cleaner. I use Parker Amchem Metalprep 79 on steel or Alumiprep 33 on aluminum. I use as many applications as necessary to be assured that the metal is absolutely rust and corrosion free. I believe these are basically dilute solutions of Phosphoric Acid with a wetting agent. I follow up on the aluminum with Parker Amchem Alodine 1201. I believe this is a dilute solution of Chromic Acid that forms a thin skin of Aluminum Chromate on the surface of the aluminum. I wear a face shield and rubber gloves, and I use a paint brush to apply the chemicals. The acids do have to be rinsed off with with water, which I know you don't want to do, but sometimes we all have to do things we would rather not do. When everything is dry after the final wash, I spray on PPG DP-40 Epoxy Chromate Primer. I have also used a similar DuPont product, and it also worked real well for me. Then comes a catalyzed primer-surfacer, a sealer, and finally an acrylic urethane base coat-clear coat paint. And one more thing; I don't use bondo. I use Evercoat Metal-2-Metal. I think it works better, but is much harder to sand. Fortunately, I have a miserable, lazy, ungrateful, life-sucking, parasitic 16 year old son who likes to help me work on cars. He makes a lot of work go real easy. Andy, in the San Francisco Bay Area, there are some paint products that the Paint Nazis won't allow to be sold here. Screw the Paint Nazis! There is a paint store in Santa Cruz and another one in Salinas where I can buy whatever I need. - Ed Peterson

Andy: I have used a product called "Extend" from my local auto parts supply store. It comes in spray or non-spray versions. Claims are made that it neutralizes rust so that you can paint over it. I have not verified that with a paint shop, however. What I do know is that I sprayed a rusty fender of an old Chevy Blazer just before winter a few years ago. The rusted sections turned black and ugly, but no further degradation occurred over the snowy, icy and salty winter -- and if anyone out there is familiar with New England roads in winter, the first line of defense is a heavy coating of road salt before he snowplows come out. I have used "Extend" to precoat bare metal that awaits painting. The metal turns a bluish-black color but no surface rust appears. - Carl Hanson, 51 XK120 FHC

Carl, Whenever I go under a car I take a can of extend with me. If I see rust I soak it. This was discussed a while ago on the XJ list...i believe it is a phosphoric acid based product, like Triple-etch and other surfasce prep materials. XKs and XJs have lots of poorly sealed seams that beg for some thin anti-rust solution. I had one door panel off my XJ and flooded the lower portion with extend so it would soak into the rust prone lower edge...I think it is doing some good. - Jim Warren, XK 140 dhc, XJ6 vdp

If you have any questions or comments send e-mail to: ted@jag-lovers.org
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