I was working on the car in the shop at work but was force to take it home. For the past year it has sat in the weather in my driveway. I had a "Wolf" car cover on it but it dry rotted and had to be thrown out. The car had a vynil top on it and when I removed it, it appeared that half the roof metal came off with the vinyl top because of the rust. The car is in good shape beside the roof and the front fenders. I sanded the car down and sprayed what was supposedly rust killer on the roof. I then spayed the car with etching primer and primed it. As you can see the rust has retuned to the roof. There is a pinhole in it somewhere because I have found water in the car and moisture on the inside of the roof. I'm scared to use a grinded because roof sheetmetal is thin anyway. I've thought of using bondo but don't know it it would make the roof to heavy because they do flex some. I've gone as far as thinking if the center of the roof can be replaced or patched with sheetmetal, even though that is a little extreme. How do I get rid of this rust? I'm thinking a vinyl top will have to go back on to cover this mess anyway. Any and ALL opinions would be appreciated. Thanks.


It had just got done raining when I took these today.

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Remove all the paint via chem stripper. With the roof in bare metal apply some navel jelly, can be found at darn near any auto supply store, I get mine from Advance auto.
Navel jelly will eat rust leaving you with nothing but clean bare metal. It does not attack metal making it thin or convert the rust into a so-called harmless substance like some other products do.

The flat out best cure is to fully remove rust not to cover it up and pretend its gone. Navel jelly will fully remove rust.

Applying bondo over rust is just a ticking time bomb, might last 4yrs or 4 days, you never know which.

A grinder does NOT belong on sheetmetal period!!! Ive seen more metal destroyed with 4.5 electric grinders then with any other tool. They have no purpose what so ever.

Your etching primer does nothing to protect metal, its made to provide adhesion to metal not protect. As you experienced, etch primers and even urethane primers can and will wick moisture right to the metal causing it rust from underneath the paint.

Once all your rust is gone, da sand the metal with 80 grit and apply two good coats of EPOXY primer. Epoxy provides the best adhesion to bare metal and also protects it, it wont wick water so you can leave it exposed to the elements. More then likely any rust pits will be taken care of when you apply your urethane primer. If not a skim coat of poly glaze OVER the epoxy primer will do just fine, but apply your filler OVER the epoxy primer dont apply it to bare metal.

Primer did it's job. To absorb.......anything on it.

The only way to find out what has to be done is to remove the primer & rust and see what's there. Wire brush it then DA sand it with 80 grit. If you end up with just a few pinholes and the sheet metal is still strong enough, you could POR-15 it to death and cover it up with another vinyl top. That's the easy way out and if you get lucky with the rust damage.

If not, then you're looking at changing out the entire roof.

Im living the same dream in my 69'.....f'kin' yinyl tops!!.......does anyone make replacement roofs?

Im living the same dream in my 69'.....f'kin' yinyl tops!!.......does anyone make replacement roofs?

They now have them for the Camino, I'm sure the Chevelle soon

Hi,
I'm in the same boat. You'll find lots of surface rust and some area's where the rust has eaten little divits into the surface or all the way through. What I did was where the metal was eaten away I drilled it out until I got to good metal. Then I place a piece of copper underneath and filled the hole with weld. Hopefully your welding is better than mine.
Rick

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The sad part is the car didn't come with a vinyl top I put one on because I like the way it looked. That's for all the suggestions keep them coming.