I took the vinal top off of my 73 today and found some big rust areas I ground them down to the metal some of the areas I am going to need to used glazing putty to smoth out the roof could I put on por-15 sand it down then smooth out the area and cover it in por-15 so that the rust won't come threw the putty?

Greg,

I had major rust spots on the top of my 69SS396. There were 2 option for me, fix the rust or cut off the top and weld a new one from a donor. I choose the first because of the amount of labor involved.

Be very careful however you decided to fix it. I had to weld a hole in the top of mine to patch it. I put a new vinyl on and 5 years later the rust came back, but much worse. I would do the following:
1. Grind it down to bare metal with either 40 or 80 grit DA sander.
2. Get some of the metal cleaner Por-15 sells
and clean the top surface very well.
3. Use the Metal Ready etcher to etch the surface and neutralize the rust. DO NOT SKIMP ON THIS OR ELSE....
4. When its finished drying, use some of the POR-15 paint. Make sure not to put too thick of a coat or else it will run.
5. You might need to put 2 coats on the spots that had bad rust.

So far I don't have any rust.However, my camino is in the garage 24x7 now. It use to sit out in the weather with the rain. The moisture underneath the top is what caused the rust on mine.

Good luck

another note. I have heard that using bondo/putty holds in moisture and that fiberglass should be used instead to keep the moisture out. Anyone else out there can confirm this?
I used a coat of fiberglass resin over the top of the por 15 to keep out the moisture.

SS, it is not that the plastic filler "holds in" moisture, it is simply not water proof. I mean, what moisture is it going to hold in? First, there would have to be an exposer to moisture, how would this happen? But if you are concerned (and rightly so, you should do EVERYTHING you can to keep the repair nice) you can use Evercoat tiger hair or Kitty hair, both are water proof.

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1965 Buick Gran Sport Convertible
1965 Buick Skylark H/T
"Fan of most anything that moves human beings"

I used ground down as good as I could and have been treating it with a product called "rust mort" now can I bondo areas and then top it off with por15 to seal it so the moisture will not come in?

I would think adding por-15 over the top of bondo would be waste since you want the por-15 over the rusted metal, not over the filler.

MartinSR. I did have an experience (lack of prep exerience) where I treated the rust with an etcher but it still rusted from the vinyl holding in moisture between the metal and vinyl. Over time, the rust bubbles started growing. My buddies GS has the same problem right now too. What is the best way to go about fixing this metal cancer?

Warning about the "Rust Mort". I used it on some places on my elky and must not have washed it off good enough and had filler pop off of those spots. The rust was killed but adhesion was a problem.

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Elcaminos are special!
I'd rather walk around with a Chevrolet hubcap in my hand than drive a Ford


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