pin holes in the bondo

Any auto body guys have an answer to my question? I have sanded and sanded my fiberglass sub box, 320 grit, i think its pretty smooth, but i have pin holes all over it. do I have to fill in every single air pocket with more bondo? What should I ignore and trust to primer to cover up. Thanks

if the pin holes are tiny, high build primer will cover them.  If the holes you are getting are a decent size, use some more bondo, but make sure to mix it correctly so that there are very little to no air bubbles in the bondo, thinly spreading this over it will fill in the pin holes, sand this down, then use high build primer.  After that it should be ready to finish.  Good luck

Do a search for glazing putty, read up. Then go buy yourself a tube. It works wonder on pinholes, scratches and other tiny imperfections.