You know how all those white plastic electronics – computers, game systems, lamps, just whatever – start to turn yellow after a few years? And no amount of cleaning will fix it, not even bleach, which tends to just hurt the plastic a bit?

A few years ago, some antique computer collectors – particularly of old Amiga, Commodore, and Atari white plastic computers – did a lot of experimenting around and came up with a solution. It’s known generically as Retr0brite, but you can make it yourself. Essentially it’s a kind of oxidation – a bromine solution is added to the plastic as a fire-retardant, and over time a hydrogen atom gets replaced by an oxygen, which rotates the molecule just a bit to expose the bromine, which looks like this:

UV light makes it worse more quickly

All this means that eventually the 1990s-era trackball that used to live in the sunroom looks like this:

Yep. That’s yellowed.

This is an old Microsoft Intellipoint trackball from the 1990s. I have four of them, one still new in box. It is, for my hands, the single best pointing device ever made. Needing to take it apart to scrub it out inside got this whole thing started.

As you can see, it’s got quite yellow over time, thanks to that UV-triggered bromine exposure. Retr0brite triggers the release of the aforementioned hydrogen, and re-replaces it with oxygen, reconfiguring the molecule just that little bit. You’re actually restoring the plastic with this process, rather than damaging it further.

Mixing up Retr0brite is actually quite simple. The only difficult part is getting the right mixture of artificial mucus, to use as a physical stabiliser. You need one, to keep the Retr0brite on the plastic, rather than running off into the tray.

Minion Paul had to leave the room

It’s just corn starch, relax. XD

I was able to get a reasonably-pure 12% hydrogen peroxide solution locally, but if I had the option, I’d go up to 15% or even 20% – just because by the time you get the artificial mucus into the mix, you’ve diluted the peroxide/TAED mixture further, and unless you have more UV than we have around here, that’ll slow down the reaction quite a bit. More is not always better – in California, this might’ve been too strong a mix.

But! After a day mostly in sunlight – result!

Not all the way back, but close

A stronger mix or a second day of sun probably would’ve finished the job. That’s against 92-brightness white paper, which actually means slightly blue; Against the brown workstation table, it’s almost shockingly white. But you can still see a difference between inside and outside of case, and I think they should be the same.

So: yay! It works! If you do this, USE EYE GUARDS, SERIOUSLY: once you add the TAED, it can get a bit fizzy, and you do not need this shit in your eyes. I can’t stress that enough. But otherwise, it’s pretty safe.

Here’s another before/after shot – sorry the second one is fuzzy, I didn’t realise until I’d put the trackball back together:

Oh, otherwise, the plastic feels unaffected. If anything, it feels a little smoother, but I think that’s just placebo effect. And if you can’t deal with the mucus, another solution is to throw out the gel entirely and make enough primary solution to submerge the plastic. The only problem there is that the plastic will float, so you’ll need to weigh it down.

So yeah, a fairly easy and effective DIY restoration project. Break out your Commodore 128s, kids, it’s time to make some old-school look brand new. 😀