I have been lurking around the paint section hoping i could find some answers but i haven't had any luck so here it is. I am working on getting my car painted and have the majority of the work done. The issue i am stuck on is the flaking paint from the previous owner's "macco job." I was wondering if sanding and feathering out with sandpaper would be sufficient or if more was involved? Underneath all the moldings and weatherstrips on the car are the original gold color which is peaking through the flaking paint now. Is 80 grit paper too rough to take care of the issue? Here are some pictures to let y'all see what i am talking about.

 

You could repair the damaged areas but the rest of the paint might have the same adhesion problem. It could just be certain places that weren't scuffed sufficiently before painting but you should expect at least a couple more areas to develop problems later. The whole car should be repainted.

60-80: used before body filler.
320ish: used before primer
400-600: used before painting
1000-2000: used before buffing

Grits can vary somewhat with the coating thickness, material being sprayed, material being sanded, tech's preference and/or the tech's experience level.

 

best thing to do, if you have access to air compressor, take a blow gun to the peeling paint areas and see how much blows off. then you can sand & feather out the edges from there. use 320-400 grit to feather and then prime.