Everything Else

This is interesting...

Nice find! There's another thread here with a link to similar/same material, I think it went into more detail of the process (or maybe one of links off of that page has it.) I think pentium may have posted it...

Perfect solution!

LOL, after I read the subject line of this thread, I was jokingly expecting to see a Billy Mays commercial.

Funny how that's basically what they used to clean up the computers...

Chris

Nice find Dr Dave!

Recipe here http://www.classic-computers.org.nz/blog/2008-12-30-de-yellowing-old-cases.htm

So who will be the first to take a greening Indy case and see if it turns Blue ?

I was thinking of trying this on an Indigo external CDROM first. But I wonder what happens in the next 5 or 10 years with plastic that has been treated like this -- will it turn brittle? get yellow all over again?

If I take the plunge, the first attempt would likely be discoloured keys on old granite Alps SGI keyboards, so the spacebar isn't two shades yellower than the rest of the keys...

It sounds like part of the problem is the UV stabilizer in the plastic. Assuming that the plastic isn't exposed to the sun, it should be OK - since the implication is that the additives in the plastic cause the colour change regardless of UV exposure. But having said that, I'm sure I have an Indy cover somewhere that's not too important, with green on the lid except where the monitor sat - which would be a perfect test.

I did a quick look and didn't see that, so I defer to the original thread. That's what happens when you go offline for a few months, busy with work and such.

More recipes http://www.vintage-computer.com/vcforum/showpost.php?p=90439&postcount=5
http://retr0bright.wikispaces.com/Retr0Bright+Gel

I'd like to try this on a few items, but will it harm silkscreened logos or text? I'd hate to successfully whiten a component only to discover that the manufacturer's logo dissolved!

It might even brighten up old green or the later blue Octane skins.

The discoloration is not as noticeable as on white or beige box, but probably still occurs to the blue plastic.


sgiSteve

Did someone mention that bunch of threads on the VCForums?
Well, if I ever had the time to actually give this a try I might see what it does for a few of my systems like a Quadra 660AV which was out in the summer sunlight for three months. Man did it get yellow.

I would doubt it. The letters on the keys are silkscreen too and they seem fine. Just my guess though.

With regards to silkscreen: it doesn't seem to be a problem but as there is such a variance between different plastics and inks as well as retrobright formulas, I would recommend trying an inconspicuous area or throwaway piece first. I'm not sure if you would find much printing on (for example) the interior side of a piece of plastic, but if you do that would probably be an ideal place to try.

If it was a big deal I'm sure previous users of the formula would have noticed. It seems to be a non-issue.

One of the users noticed a fading of the silkscreen text labels on one of the Amiga cases.
another users got his Apple logo destroyed.
So it seems it can happen but it also seems they both used an early formula of 20% hydrogen peroxide but later experiments with 6% solutions showed equally good results.
So it might be that the fading of the print and logos was due to bleaching.

Anyway, testing first seems appropriate.

//Harry

Indeed, I should have added I haven't looked much past the linked wiki page. Didn't see any disclaimer regarding screenprinting though, that is definitely something to keep in mind.

Impressive stuff! I've read through a lot of pages yesterday evening, and man, this is the greatest discovery....well....almost EVER!
I was almost ready to dump my somewhat-yellowed IBM 43P-140, but hell, i guess i'll give it a shot. Or clean up my original Indigo CDROM drive...or my brothers C64...or....
Seems that 'easy does it' works best, apparently this way the plastic won't suffer...but indeed, be very careful with the logo's etc.

They tried blue plastic...this got marked, but in that experiment they used bleach, so maybe it'll work with peroxide. Hmmm, got a green-blue cover laying around somewhere...
Guess it won't hurt to check for ingredient availability over here

This is somewhat off-topic, but the Mr. Clean Magic Erasers, while they work unbelievably well for removing gunk and scuffs, will take your model and serial numbers off with just a single careless swipe.

So while my onyx now looks like it just rolled off the assembly line, it also has hand-written model and serial numbers (just in case I ever need them for an odd reason they will still be there)

Bump up an old thread...

Has anyone tried this on your colored SGI equipment yet?

I have some noticeable yellowing on my Indigo2's and would love to put them back to normal.

I am wondering if this would destroy the color or not...