I recently dis***embled my 40 Ford project and sent the fenders, hood and trunk lid to the media blaster. I got everything back earlier this week and need some help on how to start getting these panels ready for paint. The car was last painted around 1970 - the blaster took everything down to bare metal with the exception of a few places that still have body filler in them. Should I remove these spots with a grinder or primer over them? They appear to be bone dry and have stood up well for 40 years or so, but am I better off grinding them out and redoing them befoe priming? Next question, should I use epoxy or etching primer? I've heard it both ways and I simply don't know which way to go. Third issue - the rear fenders were patched at the trailing edge with bondo, the patched area being roughly one to two inches in height and running about a foot in length. Am I better off welding in a patch panel or should I redo the bondo? Thanks for any help, and thank goodness for this forum.
Alot of what your asking will come down to personal preference, the bondo, well its held up this long no since in grinding it out now if you don't feel like it IMO, but I like to have as little filler in all areas as possible so my vote would be patch panels but if your welding skills aren't all the way up there you're going to end up using filler anyway, now as far as surface prep; depending on what the blasting has done to the surfaces normally I would just scuff them up very lightly then clean real well with acetone, then tack cloth and spray. I use a combo of the ppg self etching primer then ppg k36 primer surfacer. The surfacer is real thick and takes some prep before final paint but it also will fill all the little dings and imperfections you may have missed. The self etching primer is great because the specific kind is ok to shoot right over filler.
i myself would dig that filler out and replace new or straighten out the spots would be better. as for getting the pieces right for paint i second, self etch prime then high build like 2k primer . then you can put a guide coat on before you block it out to see if theres any imperfections. block with like 220 then 400.. if you want to take an extra step. block it out with 220 then reprime again. then final block it out then your nice and straight for paint
roadsterrod said exactly what i would do. even though the old filler is still in good shape the stuff we have now will last even longer. plus you can hammer more of the dents out and use less filler which is always better.
Wipe down and blow off the part's. Epoxy prime ASP. Dig out the bondo. Keep your hand's in glove's to prevent oil's from the bare metal surface.
From a personal standpoint, I always want to know what the bondo is actually hiding. Once it's all gone then you can decide to either straighten/replace metal or re-bondo.
Hey, I'd remove any old filler and replace any bad metal with good prior to any other work. Rather than shooting a bunch of expensive etch & surfacer on the panels right off, I'd first block the panels with an idiot stick after a guide coat had been shot on them. Be very careful to cross hatch pattern every square inch of the panels, and either metalfinish any damage you discover, or lightly bump up said damage. If your a filler-over-primer kinda guy ,than etch prime and mud as necessary, with surfacer over the repairs you've discovered & filled. The pratice of using surfacer or high-build primers to "straighten" a wave or damage in a panel is a piss poor one, and usually costs more in time & material than had the panel been repaired properly to begin with. Good luck with your project, S****ey Devils C.C. "Meanwhile, back aboard The Tainted Pork"
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