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Hey there. I am in the process(long process) of building a 34 Olds 3 window coupe and just started on some body prep. Under the nemerous layers of paint are areas with rust pitting. My question is- What should I fill these areas of pitting with? I have stripped and fine sanded over the pitted area and don't want to sand anymore as some of the pits are fairly deep. What are the thoughts out there for this problem? Thanks. Mike
 

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Mike, I had a similar situation with my 55 chevy. The roof was the biggest problem. ANY rust that is allowed to remain will come back to haunt you. I have heard a million claims of all sorts of products that will convert rust, encapsulate rust, blah blah blah. The only 100 percent sure way is to get rid if it. My solution was a spot blaster, a bag of aluminum oxide media and a LOT of patience. I had my body on a rotisserie which made it easier. I blasted those pitted areas an inch at a time and as I completed a section I used a wash coat of acid etch primer out of a spray can to hold the metal from flash rust. That will all be sanded off later when it's time to skim coat the area with filler. The acid etch will remain in the pits and seal them under the new filler/primer/sealer/paint. I used one of those harbor freight cheapy spot blasters. The aluminum oxide cost me more than the blaster but it worked great. There you have my two cents! Hope it helps.
 

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I have the same problem. Iam getting as much rust out of the pits as possable. Then Iam useing Zero Rust as my first coating. It will prevent the rust from comming back like POR15 dose but its sandable. Then I get a can of High Build primer filler and spray it pretty thick in the pitting area in several differnt coats. Then I wet sand it with 220 git paper and repeat with anther coat of Zero Rust and Primer filler and wet sand again til the pits are all filled in. Iam sure there are many differant ways of doing it. I used this process last weekend on areas that are difficult to use body fillers.
Good luck!
:D
 

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Whenever I encounter rust pitting I blast and apply a rust inhibitor/neutralizer as the above state. However if the pits corrupt the integrity of the metal; they are deep enough to weaken, soft when pressed w/screwdriver, or any holes through- I will cut out the entire panel and replace. Better to be sure than to have to do it again. Good luck!
 

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I've said this before here and I will say it again. In order for metal to rust, it must be exposed to water and air. If you can stop the air and water from getting on the metal it will not rust. I recently bought a wheel for my Model A Ford. It had rust pits galore on the outer surface. It also still had a tire on it. When I removed the tire, the inside of the wheel was in perfect condition, absolutely no rust. Why? Because the metal was protected by the paint and the paint was protected by the tire. Painting metal will stop rust provided the paint is applied in sufficient quantities to prevent air or water from penetrating it.

All you need to do is remove the loose scale with a wire brush. I use one on my grinder, then clean with enamel reducer or DX 330, then prime, and block sand until the pit is gone. You may have to prime and block three or four times to get the pit back up to the level of the surrounding area. I have done hundreds of rusted areas in hundreds of cars like this in the past 35 years and have not had a problem.

Benji
 

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I gotta agree with Benji. Ten years ago when I stripped my 57 chevy truck it was 50 % rusted surface. I blasted it to get all that i could off with out distoring, primed and painted. It has not come back in 10 years.

Same reason everyone recommends the POR-15. It is a good sealing primer to stop rust growth. It does not change the composition of the rust, it just stops it from growing.

chris
 
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