I'm currently working on a little DIY project to repaint the metal outer case from an old IBM PC that unfortunately sat in an attic for 20 years and rust got the better of it. The case is heavy-duty metal with a low-lustre (or maybe matte) painted finish and a texture. It's not terribly unlike any other 1980's era PC cases, though these early IBMs tend to be of more industrial quality than many.
I removed the rust using a paint decontaminator product that did quite a good job of removing the rust. I lightly wet-sanded it with a synthetic "steel wool" pad to remove any loose paint, but have been trying to do the minimal amount of sanding to preserve the original texture as much as possible. I then sprayed a couple of coats of gray automotive primer and repeated the light sanding between coats, which has come out quite nice. I ordered some custom spray paint that's supposed to match the original color, which I haven't yet applied.
What I'm not sure about next is whether or not to add a top/clear coat, which would be to add long-term protection against bumps and scratches. This case is meant for monitors and other things to sit on top and slide around, and might have questionable condition bottoms or feet. Of course it's size and weight means it's likely to get bumped around on walls and things while being moved. Ideally a top/protective coat might add a tiny bit of shine, but otherwise not alter the texture and look of the paint.
A couple of thoughts:
- Polyurethane - either wipe-on or spray. Is this compatible with paint? What would this do to the paint finish, worried it may dull the color?
- Paste wax - apply several coats of high quality paste wax. Nice look, but not durable or permanent. Easy to remove if I don't like it though.
- Paint-based clear (example COVERMAXX type of stuff) - concerned about quality/appearance of final look, plus don't want to risk bubbling the underlying paint.
- An automotive "paint protectant" product - probably similar to wax in that it's not going to be too permanent.
- Other automotive clearcoat products - probably good compatibility with the primer but intended for outdoor wear, might be overkill? Also, might be mostly gloss finish.
Would really love some suggestions for the best way to go here.
Just to give some visual about what we're talking about here:
Note to mods: I posted here instead of Retro Computing because I don't think this is specific to painting just a computer. But happy to move it if this is off-topic.