Down to bare metal -- Surface rust

Ele115

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People have been mentioning bare metal and how to address it. Of course, there are going to be 2,342,782 different "right ways" to do it. I have a way that has worked for me for years.

My 78 has the original paint, but rain dripped onto it and got through the paint. This paint may look good, but it's over 40 years old, a fart can go right through it. I took the deck lid off as that's by far the worst. I am doing the whole car, but the booth is full right now. I have to move a lot of stuff around to get to it. If the color is a mile off I will know right away.


This is it.

Decklid rust rotate.jpg




Decklid rust2 rotate.jpg


As is always the case, it's a lot worse than it looks.

Decklid rust4 rotate.jpg



These pictures were taken after stripping and Ospho. The Ospho was allowed to completely harden, then the decklid was DA'd with 80 grit and it got two coats of Axalta Variprime Etching primer 617
 

Ele115

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The etching primer was allowed to flash about 45-50 minutes. High humidity was why I waited so long here. In the booth, I would have cleaned the gun and put the primer right down, about 12 minutes. After 50 minutes, I gave it two coats of primer, and some black guide coat.


Block sanding sucks. If you like a car laser straight, suck it up and get used to lots of block sanding. This took 3 hours
Decklid paint3 rotate.jpg




The black shows imperfections and low spots. There aren't many as this car has never had body work or dents.
Decklid paint2.jpg




I used a touch-up gun to hit all the edges and cut-throughs with etching primer. I actually did the entire outer edge because it's easier than trying to spot every little minute area that I sanded through, there are a few but my eyes aren't that good. Easier to dust all the way around the whole thing. Any bare metal must be shot with the Variprime immediately. Leaving bare metal is a no-no, especially in Flo-Duh. Rust starts in under ten minutes.
Decklid paint4 rotate.jpg

More to come.......
 

Ele115

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Ok, I'm kind of going to go into a few basic "why" for some of you. Some know, some don't. Bare metal is different. Not a lot will stick to it. The etching primer is the key, and if your state hasn't yet banned zinc chromate, that's the best. It's especially important on aluminum and steel. You just can't put paint onto bare metals. Some epoxy sealers will bite in and stick, but many wont. Some of the better epoxy sealers you can just coat bare metal with, then do body work onto the sealers and paint over it all. If you use the etching primers, the fumes are just deadly, a lot of acids. That's what makes them "etch". The turquiose etching primer/paint Russia uses was so strong they could just spray it onto bare metal ships and planes and it was permanent. It killed a lot of people, they don't have OSHA there. They just spray that kind of stuff on everything because people can be replaced, no pensions.
 

Aspen500

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That zinc chromate stuff works excellent and,,,,,,,,,,,,block sanding is a necessary evil but also very tedious and time consuming. Worth the pain though, once that top coat is on! Wet sanding and buffing the top coat is even more tedious. Get it smooth with 1500, then do it all over again with 2000 grit, then 3 steps of buffing. Used to be a lot easier when I was younger, lol!

Don't mean to demean your method here but a longer block, along with contour sanding blocks can get it even straighter. I try to use the longest block (actually sanding board) the panel can take and then those contour foam blocks for the the odd shaped parts. All depends on the panel and it's shape of course.
 

Oldiron440

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If it's rusting in ten minutes you don't have it free from rust and no matter what you put over it it will fail.
 

Ele115

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Rust starts as soon as bare steel and oxygen get together. It will be a while before it's visible, but it starts fast. If you leave bare metal exposed, you'll get what you get, especially in the more humid environments. One of the reasons old Mopars rusted so bad was the areas that were unpainted/under-painted when they left the factory. That's why you pay so much for a mint B body as opposed to some other brand. Someone paid huge money to replace 90% of the sheet metal. I went through this several times and am not willing to do another one.
 

Ele115

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Got this done a few days ago. Good enough for me. Going to take the deck lid back off and do the rest of the car. Hopefully I can break every single moulding clip.
Woody gun.jpg
Decklid painted left rot.jpg
Decklid painted left edge rot.jpg
 
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