Whitening a yellowed IICI: first step.

[OtakuMegane]

For lightening Macs I just use an even 50/50 mix of Clorox Outdoor and water, give it some good sun exposure and spray it over 3-4 times. Even very badly yellowed Macs I can at least get down to a much more pleasing beige color. Milder yellowing can turn out virtually indistiguishable from the original platinum. The process preserves the texture but does kill some of the sheen. Still experimenting with the best ways to restore that.

This is a very aggressive recipe that will whiten the case (definitely) but which will reduce the strength of the plastics. We are looking for a recipe that will whiten the outside of the Mac without attacking the structure of the case.

True, though I personally haven't seen any problems in normal use. Seems as strong as it was before. I also have never soaked anything, just a spraying over the outside.

Sadly everything I've ever come across or thought up myself for a gentler process still involved abrasives that remove plastic, once you get down to the core of how it works.

 

[CtlClick]

Very nice job. I cleaned off my yellowing IIci about four years ago. I scrubbed it with a conet solution until it returned to the original color, but there were some very noticable stratches on the front of the case where it had been mishandled during my last move. I tried to buff them out, but just ended up painting it black

 

[yestermac]

I sandblasted the yellow off a Classic II, Mac Plus and Q700. Works better then sandpaper. It leaves the surface a little rough but surprisingly you can actually smooth it out by just rubbing it with your hand. Only downside is you loose the lettering. It would be possible to re-letter it. I've seen it done on other hacked macs. Of course not everyone has an air compressor and sandblaster but maybe someone you know has one. I used silca sand which is very fine. The whole job takes about 30 minutes. Higher air pressure (100PSI) worked best.