VOGONS


First post, by Intel486dx33

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I have some old computer cases that have Yellowed.
What is the latest Ideas on DIY Whiting solutions and Methods to Whiten Plastics ?

Is it just Hydrogen Peroxide and water bath ?

Reply 1 of 13, by wiretap

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Developer 40 volume liquid + distilled water + 2x 60 watt UV LED flood lights. That seems to yield the most even results, and it does the job in just a few short hours.

Circuit Board Repair Manuals
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Reply 3 of 13, by brostenen

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Just search YouTube. There are always some new idea on how to fix up plastic. The question is. Do you dare do what they have done?

Don't eat stuff off a 15 year old never cleaned cpu cooler.
Those cakes make you sick....

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Reply 4 of 13, by Horun

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Why ? Just curious because like copper, brass, silver and other things ... the patina effect is part of nature and to reverse or remove it is detrimental to the object being reversed. It can lead to the item becoming more brittle or actually loosing value. Guess no one here is an antique or coin collector.

Hate posting a reply and have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. 🤣

Reply 6 of 13, by hwh

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Horun wrote on 2020-03-16, 02:13:

Why ? Just curious because like copper, brass, silver and other things ... the patina effect is part of nature and to reverse or remove it is detrimental to the object being reversed. It can lead to the item becoming more brittle or actually loosing value. Guess no one here is an antique or coin collector.

Uh I don't think that's fair. Few would say that the brown "patina" of aged plastic is beautiful or "authentic." It's as if mildew grew on a painting and you protested an effort to remove it. Well, sure it's not as original as it was. But that doesn't mean you aren't making a great improvement in the condition of the item.

And no one wants to do anything to damage their equipment. This is a complicated problem and unfortunately weird behavior is required to treat it.

Reply 7 of 13, by derSammler

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hwh wrote on 2020-03-16, 10:12:

Few would say that the brown "patina" of aged plastic is beautiful or "authentic." It's as if mildew grew on a painting and you protested an effort to remove it.

While I agree on the point about esthetics, the comparision with mildew on a painting doesn't work. Yellowing of plastics is just a color shift - it does not cause any harm (well, to your eyes maybe). Trying to get rid of it often does, however, and the result won't last that long either. If the yellowing is uniform, it often doesn't even look that bad.

As for "authentic": only keeping the yellowing is authentic by the meaning of the word. That's why no one would even think about polishing ancient statues made of bronze. If you try to remove an item's showing of its age, it's no longer authentic.

http://retro-net.de/blog.html

Reply 8 of 13, by sf78

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derSammler wrote on 2020-03-16, 10:37:

As for "authentic": only keeping the yellowing is authentic by the meaning of the word. That's why no one would even think about polishing ancient statues made of bronze. If you try to remove an item's showing of its age, it's no longer authentic.

I agree on this. Yellowing and all the scuffs and scrapes show the items age and makes it unique. If I would polish and retrobright all my computers they would look like new from the store and lose some of their character in the process.

Reply 9 of 13, by Imperious

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I successfully de-yellowed my Apple 2e by simply putting it out in the Sun on days below 28 degrees C.
This did take a week of sunlight exposure but it does work.

If You want to use the Hydrogen peroxide method then submerging in water with either Sun or UV lamps is the best to avoid the marbling effect.
Never try this on dark keys from a keyboard as it can over bleach them.
If You have to use hydrogen peroxide on darker plastic don't do more than a few hours.

You could test with something small. I have a Microsoft Optical USB mouse that is beige, I successfully de-yellowed that twice, first time with
Hydrogen peroxide, then with just sunlight the 2nd time. yes depending on various factors they will Yellow again.
I haven't noticed any detrimental effects on the plastic other than marbling which is avoidable if careful.

8 bit Guy has quite a few videos on this.

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Reply 10 of 13, by pewpewpew

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Horun wrote on 2020-03-16, 02:13:

Why ? Just curious because like copper, brass, silver and other things ... the patina effect is part of nature and to reverse or remove it is detrimental to the object being reversed. It can lead to the item becoming more brittle or actually loosing value. Guess no one here is an antique or coin collector.

Is this the first thread that's had a serious kick at valuing the yellow?

It would be another of those small shifts. Like recently, towards repairing CD-ROM drives, and fussing about finding the period correct motherboard standoff. It's fun to watch happen.

One of my favourites was watching radio collectors shift from a broad loathing of postwar HAM mods to WS19 sets, to valuing those mods and those people as history on its own.

[Nope. Can't bear the yellow, here. Looks like nicotine stained teeth. If it simply faded whiter, or anthing neutral, I'd probably be okay with it.]

Reply 11 of 13, by hwh

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derSammler wrote on 2020-03-16, 10:37:

While I agree on the point about esthetics, the comparision with mildew on a painting doesn't work. Yellowing of plastics is just a color shift - it does not cause any harm (well, to your eyes maybe). Trying to get rid of it often does, however, and the result won't last that long either. If the yellowing is uniform, it often doesn't even look that bad.

As for "authentic": only keeping the yellowing is authentic by the meaning of the word. That's why no one would even think about polishing ancient statues made of bronze. If you try to remove an item's showing of its age, it's no longer authentic.

Yes it does. I'm sure we could go in circles with analogies if I had any desire at all to do that. Condition, cleanliness, aesthetics. We want machines as they were, not moldy, dirty, cracked "authentic" machines which, for all the "integrity" of their lack of care, hardly resemble the beauty of when they were in circulation.

If you think yellowed plastics are handsome, by all means, leave yours that way, but don't give me a yarn about "authenticity" and ancient statues like we're looking at an archaeological sample.

Reply 12 of 13, by Swiego

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I’ve found UV led strips to work well - with the right bucket or tray the setup is easy, and ensuring even exposure becomes trivial.

My latest kick has been figuring out how to carefully remove paper stickers, labels etc. such as found underneath keyboards, then reattaching them afterward. A heat gun makes removal quite easy. I’ve used spray adhesive to reattach.

Reply 13 of 13, by mongaccio

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I've recently made some 'Retrobriting' since the Sun here starts to be a little bit warm , and i have lots of free time thanks to the Covid 19

Wanted to try the liquid peroxide method, but it is not sold around here.
I did use the usual cheapest 40% peroxyde cream , 1 liter for under 4 EUR.

First keyboard, NTC branded Pc keyboard. Tried to make a little experiment here:
Poured some cream into a jar of water, and tried to see if it was effective, at least for the keys.

It was not effective at all. Too diluted/too opaque.Had to apply the cream with a brush for each key.

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Cream+brush+sun had a decent effect. I also treated the floppy drive bezel you see in pic, it was really yellow.

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The Keyboard plastic frame was perfect just after a couple of hours, the keys needed an entire sunny day to lose the yellowish patina.

The only downside with cream is that with some plastic you may risk some Marbling effect. Happened to me just once, i had to paint the piece in question.

Next i did retrobrite some really yellowed C64 keys
Before

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After 2 days of sun.

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Same method, 40% cream , brush and sun. I cleaned 'em all and reapplied the cream for a 2nd day of exposure to the Sun, this yellowing was too stubborn.