Exploration into the Retr0bright world...

Hello everyone! I would like to share my experience restoring old computers to its original (or close to) beige/grey colour. 

If you are reading this post, chances are that you know what retrobright (or retr0bright) is. In any case, here is a short explanation: ABS plastics were largely  used in computers and game consoles in the 80s, 90s and early 2000s. Plastic manufacturers mixed bromine within the ABS formula to give these plastics fire retardant properties. With time, these ABS plastics turn yellow due to a chemical reaction between the bromine and UV light (radiated plenty by the Sun and also fluorescent lights among other sources).

The state of my vintage Apple keyboard prior to the process

In the world of retrobright, there are a few different techniques. I recommend watching these videos as a starting point:

- Adventures in Retrobrite - New techniques for restoring yellowed plastic! by The 8-Bit Guy

- Retr0bright - de-yellowing do's, dont's, and playing devil's advocate - by Modern Classic

- A new way to fix yellowed plastics indoors? by Adrian Digital's Basement

After some research, I opted to buy the following prepaid mixture that was recommended by a few computer/console collectors: Creme 40 Volume Developer 

All you need is:

• Creme 40 Volume Developer 
• 303 UV Protectant (to prevent re-yellowing)
• A 2" house paint paintbrush
• Cling wrap (or zip lock bags)
• Microfiber cloth
• Kitchen gloves (the cream 40 irritates the skin and you will feel your skin burning if you touch it)

Now, the hardest part: you need to disassemble everything and only leave the outer plastic casings of what you want to retrobright:

After running a test batch on an Apple StyleWritter II  I decided to do a bigger batch on my second attempt. In this batch, I retrobright(ed) my: 

• Macintosh SE
• Macintosh SE/30
• Macintosh IIsi
• 2 Apple Extended Keyboard II
• 2 Apple Desktop Bus Mouse

A few photos of the disassembly process:

I recommend you doing only a couple computers at a time as it may become messy to keep all parts scattered while you wait for the process to be completed. 

Using the 2" wide paintbrush, I applied a good layer of the Cream 40 on each sides of each plastic piece (including the space bars from each keyboard who were the only keys made of ABS and thus had yellowed). Then I wrapped each piece in cling wrap (this is to ensure the cream 40 wouldn't dry out in the sun before the process/clearing was over).

IMPORTANT: To minimize streaking (discolouration marks) you need to try your best to apply an even layer of cream 40 accross the whole piece and avoid wrinkles or air bubbles when applying the cling wrap. It is not an easy task, but this will minimize the risk of streaking.

I added the Mac SE/30 case (on the left side on the photo below) an hour later and you can already see the difference from the Mac SE case (right side) beside it:

I left it in the sun for about 5-6 hours, constantly rotating and checking if any parts had the cream 40 dried out (I re-apply it if it was the case).

After these time in the sun, all parts were washed in soapy warm water and left to be air dried.

After the parts were dry, I sprayed a thin layer of UV protectant 303 and dried it with a microfiber cloth. This UV protectant should protect the plastic from UV light and slow down the re-yellowing of the plastic.

Drying out the UV protectant with a microfibre cloth

I also applied UV protectant 303 in the space bar before re-assembly the keyboards

And now... the results!

The Macintosh SE/30 faceplate before and after the process. It wasn't too yellowed, but you can notice the difference

The keyboards and mice look brand new!

The Macintosh SE faceplate was very yellowed and it looks much better now

Overall, I am really happy with the results. It clearly de-yellowed the plastics as the photos above shown (trust me, it is even more impressive in real life!). 

However, it is not 100% perfect or fail proof. Despite my efforts to avoid streaking, I did get a few light marks probably due to some cling wrap wrinkles I couldn't get rid of. I also didn't distribute the time over the sun equally on each side for every piece, causing some small difference on the tones of grey achieved per side. 

Well, life isn't perfect either, despite these I would still strongly recommend this process as the pros out-weight the cons.

I hope you enjoyed learning about my experience. Stay safe!