I have a 1992 S-10 blazer I am working on restoring along with an engine swap. the frame was quite rusty, I do not have a sandblaster or access to one so I used a rotary air sander to sand the rust off and did it by hand in the areas I couldnt get with that. I then coated it all with Black spray primer or paint but it seems to scrape off easily. my question is, what can i do with this primer/paint in order to get something to protect the frame from future rust.
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