I have an IBM XT 286 which has essentially the same case as the original IBM PC. It has a few minor blemishes, some places where the paint has been chipped off, and some tiny spots of rust. How should I go about restoring the paint?
The case is metal and has two tones of grey/off-white. The paint is also textured. I'd like to preserve the original look as much as possible.
The old computer cases I saw were some pretty thick sheet metal, almost exactly like old car bodies from pre-1970s (enough metal that they can rust outside for years and still be sanded down & used without having holes everywhere). Treating it just like a car body paint repair would work fine.
It sounds like it's just a couple very small spots, so I would just use a tiny piece of sandpaper to get rid of only the rust, then paint the bare metal to match. Primer might be optional if your paint doesn't need it, but it could "fill in" more of the void if that's required. Scratches could be filled using a very fine brush or even a toothpick to just fill in the crack.
Auto paint has a rainbow of colors available, you might find a match in a tiny pen-like bottle, or get some custom colored to match. Check what house paints are available too, it might be cheaper to go to a hardware store like Home Depot, Lowes, Rona, etc for custom colors too.
Matching the texture would be more difficult. If the spots are very small & you wouldn't notice the missing texture from just looking, I'd probably just skip it. But there are techniques to get textures in paint using special paints, or additives, or using sponges or rags or brushes or combs. Again house & furniture paints have more texture options, searching for "textured paint" led to this Home Depot link on Textured Paint, definitely practice on a piece of scrap first.
'Original look' is at least debatable, if not a myth. If you're serious about history, then preserve the scratches as well. Clean them, and, if needed, add some conservation wax or alike. Nothing that can't be removed later on again. For storage/use in a controlled environment like home / office / museum without intense stress there is no need to be protected against more than necessary.
Your question touches a rather sensitive area: How to handle heritage. And as with any emotional topic, there are various viewpoints and answers.
Actual museum strategies are geared toward preserving the history, not just some fictitious perfect state. Every prop has a history. No matter whether they are funny stickers on a screen, holes for a reset button, or faded key caps for the most used keys. These markings carry at least as much history as a certain special edition paint job, if not more.
Especially when considering that our computers are usually a mass produced wares. Maybe compare it with a book. Lets say an ordinary 1890s physics school book. Nice find. Now take the same book with markings of a school boy. Less interesting? Shouldn't they be removed? To make a perfect book again, maybe. But what if the kid was named Albert and later became somewhat famous? Is a flower on page 32 now more important? Well, I'd say it doesn't matter, as it tells something about the user and how bored he was during that lesson. No matter if he later became famous as a scientist or lived an ordinary life as butcher.
If we want to preserve our heritage, we need to think about history, not shiny things.
Of course, being the techno-nerd I am, I will always prioritize functional restoration above everything else. But as soon as that is given, history gets priority.
P.S.: Feuer frei :))
