So I bought a replacement drivers side door off an old bronco. It's in much better shape than my door but not perfect. I removed all the paint off the outside of the door to bare metal. There were 3 spots on the door that had rust spots all at the edge of the door. One is a few inches below the keylock. The other 2 are on the outside of the door at the bottom along the base. The rust spots are not bad enough that the door rusted through, however they are bad enough that they pitted the metal.

I applied some muriatic acid and scrubbed the areas with a toothbrush. after an hour of apply, scrub, and repeat several times I was able to remove all of the rusted spots out of the pits. I then covered the door with baking soda and rinsed everything off to counter the acid. I also hit the door with some wetsand paper to take off the top coat of very light surface rust that had formed since I first removed the paint. It was very very light.

After I was done sanding I dried the door with a towel and laid it in the sun to fully dry. Once it was dry I sprayed the bare metal with self etching paint (rust oleum rattle can). I even sprayed over the pitted rust spots. Once that dried I applied several light coats of bondo to the pitted areas. I need to do some more sanding to get it flat but I'm on my way to getting it smoothed over.

My question is should I use a top coat bondo such as 2 part professional glazing and spot putty to get an even smoother finish? (See link) Professional Glazing and Spot Putty by Bondo - Part 801 - Advance Auto Parts
I'm not looking for a professional paint job but the rest of my truck's paint is in very good shape for an 86 and would like the door to match as close as possible. I have rattle can paints (plasti-kote and duplicolor) to do the 2 tone paint job. But before I apply the next application will be some sandable primer (rattle can) once I get the rust pitts finished.

I know rattle cans aren't the weapon of choice for painting but I'm not trying to be a professional and I'm only painting one door. Anyone have any comments, advice, suggestions?

 

You don't really need glaze unless you're having a pinhole or sandscratch problem. If you sand your bondo fine enough and use guide coat, you should be able to skip the glaze. However, spray can filler primer is very thin. It may take more coats to bury the bondo than it would to bury the glaze, but the difference will be minor.