Just had my parts media blasted down to bare metal. 1. Frame: clean, prep, etching or epoxy prime, then one of those black primers like Eastwood's Chassis Black or do I just lay down Chassis Black to the bare metal? 2. Suspension parts- same as above? 3. Inner fenders? 4. Floors? 4. I know external body panels, like fenders, doors, hood, etc, all get the full work up. Thank you!
Epoxy primer provides corrosion protection. https://tamcopaint.com/collections/primers/products/dta-epoxy Then apply your chassis paint to get the gloss level you want. External panels try to stick with whatever paint system you plan to use.
If you plan to topcoat your epoxy, make sure you spray it within the time limit the epoxy's tech sheet says...or you'll have to scuff before topcoat. I waited too long or one of my parts before I shot the Eastwood chassis black (which is a really good gloss level) and it flaked RIGHT OFF when I went to tighten a bolt down on top of it.
Lots of options for blasted parts. I always DA sand blasted parts to level off the surface and give the surface a nice finish for good adhesion. I like epoxy primers tho there are other good choices. I prefer the primer then top coat since is gives the opportunity to correct surface defects such as pitting. You can use just a black epoxy primer without a top coat, Dupont DP-90 was popular. Epoxy primer + the black topcoat of your choice, like a single stage urethane. Eastwood says you can apply their Chassis Black over primer or Direct-To-Metal (DTM):