How to Restore Old Computers to Their Original Color
By Gabriel Torres on January 30, 2013


Plastic parts of older computers become yellow or brown over time, so you end up with a computer that looks yellow or brown instead of white or gray. In this tutorial, we will show you how to restore old plastic parts to their original color by using a homemade peroxide-based solution called Retr0bright.

First of all, we must explain that we are not the inventors of this solution; we are giving full credit to the original group that developed it. Also, on their website, you can see the original recipe and alternative recipes for this solution. We won’t repeat what is already written there; we will show you some results we got from using this solution and some tips.

You will have to disassemble the computer on which you want to use Retr0bright, and remove the plastic parts that you want to restore. You can’t leave the computer assembled, since you will need to wash the plastic parts several times, and obviously, you don’t want water touching the electronics of the computer.

You need to clean the plastic parts very well before starting the process. We recommend that you clean them in a utility sink using a sponge and detergent.

Basically, after creating the solution, you must apply it to the plastic part you wish to brighten up with a paintbrush (don’t forget to wear safety goggles and gloves while handling the solution), and put the plastic part under ultra violet light (a.k.a. “black light”) for a couple of hours. (Some users report that placing the parts under sunlight works just fine.) After this time has elapsed, you should check the result, washing the parts in a utility sink with a sponge and detergent.

If the parts are already the way you want them to be, great. Otherwise, you should apply more Retr0bright and repeat the process for two more hours. From our experience (at least where we are located, which has very dry weather), the solution dries after about two hours, and that is why we recommend the two-hour cycle.

Some parts will clear in just one two-hour cycle. Others will require several cycles. We will give you some real examples on the next pages.

In Figure 1 you can see some of our plastic parts under ultra violet light. We had so many old computers in our collection that we created a box with four UV light bulbs in it and applied a reflective foil around the inside panels of the box.

Retr0brighting our old computer parts
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Figure 1: Retr0brighting our old computer parts

Before using Retr0bright for the first time, we recommend that you test the procedure with an old plastic part that is yellowed and that does not belong to your computer, so you can better understand the process and fine-tune it, especially because of the caveats (see last page).

Real Examples

In Figure 2, you can see two cases for Macintosh SE computers. The one on the left is very yellow, while the one on the right had already been brightened up with the described procedure.

Old computer before the process (left) and another computer after the process (right)
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Figure 2: Old computer before the process (left) and another computer after the process (right)

In Figures 3 and 4, you can check the before and after pictures of a Macintosh SE case. This result was achieved after two two-hour sessions.

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Figure 3: Before

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Figure 4: After

And, in Figures 5 and 6, you can look at the before and after pictures of a keyboard. This result was achieved after six sessions during a weekend. We had trouble with the space bar, as you can see.

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Figure 5: Before

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Figure 6: After

There are, however, some caveats. Let’s talk about them.


There were two major problems we faced while using Retr0bright. The first one was the creation of white spots on the plastic part we were trying to restore. See Figure 7. We discovered that this was caused because we bought a peroxide solution that was too strong (40 Vol.); in our next Retr0bright batch we diluted the peroxide with water, and this problem was solved (instead of using 500 ml of peroxide we used 400 ml and added 100 ml of water). You will also see plastic parts getting white spots if you try to run too many Retr0bright sessions.

White spots caused by a Retr0bright solution that was too strong
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Figure 7: White spots caused by a Retr0bright solution that was too strong

The second major problem is regarding parts that are painted in other colors, such as logos. You should take extra care of them. If possible, protect them. Otherwise, the Retr0bright solution may discolor them. See what happened with the Apple logo from our keyboard in Figure 8.

Discolored logo
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Figure 8: Discolored logo

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