Retrobright 2.0 - No more UV light!

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Wodan
ISO Advocate

14 Jun 2018, 19:50

Inspired by a video by the 8bitGuy where he is trying different approaches to "retrobrightening", I have picked up on the temperature controlled approach.

Here's the inspirational video:
First thing I noticed was that this dude is using insane temperatures on the ABS. His attempts were made at ~70°C which is far too hot for ABS plastic and comes with a high probability of bleaching out the ABS. When talking to our Mike about my first results, he pointed out he was getting terrible bleaching on his caps using the same temperatures I was working with AND he also pointed out that 8bitGuy has clearly bleached out his temperature brightened cap as well.

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This was not a result I was looking for and I think it is very important when working with this method to differentiate between BRIGHTENING and BLEACHING caps.
Brightening is what you want to so - reverts the yellowing, effectively brightening the cap up.

Bleaching is what you want to avoid and means the temperature changes the original color of the ABS plastic.

What I found really really hard to determine - especially with these more exotic beige/grey Cherry caps - was the original color. When is then yellowing gone and when did I actually bleach a cap. Tried my best by looking at the bottoms of caps and comparing them back and forth trying to find out when a cap is really brightened and not bleached ...

Keep in mind this is all a work in progress and it is generally a SLOW chemical process but the first results I have gotten were breathtaking and I am too excited to keep them back any longer.

My first approach was using my ultrasonic cleaner. It comes with a heating function that will heat up the whole tank to a desired temperature. Default temperature is 50°C so that's what I started off with. So pre-heating a container with water to the desired temperature is step one.

Step two was taking a good old ziploc bag, putting all the caps in and filling it with enough hydrogen peroxide so they comfortably float in there. Squeeze as much of the air out of there as you can.

Step three is to submerge the whole bag in the heated water and let it sit there for a couple of hours. It doesn't hurt to keep checking on your bag because gas will build up in your ziploc bag and might make it float. The process takes time, especially getting the last bit of yellowing out requires a lot of patience.

My first experiment was caps from a set of caps that I thought were beyond saving. Got them from one of these Cherry OEM G80s with Nixdorf branding and the F1 - F30 keys:
Spoiler:
Before with reference:
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During:
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After with reference:
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So after this I decided to brighten the rest of the gang, hope this picture captures the BROWNING of these caps:
Spoiler:
Before in the bag with the peroxide:
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During in the ultrasonic cleaner:
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Upgraded to a sous vide cooker:
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Seems like the ultrasonic cleaner wasn't REALLY good at holding the temperature and caps like the Control key got a little bleaching:
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Then realized I forgot a single key:
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After spending roughly 6h in the peroxide at 50°C sharp:
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Please note that I consider the SHORT SHIFT key slightly bleached!
Several lessons learned here already. Temperature is VERY important and should REALLY never be higher than absolutely necessary. It felt like the heating feature of the ultrasonic cleaner was a little too rough and gave me bleaching on some of the caps. The sous-vide thing on the other hand is made to maintain a temperature with 0.2°C deviation. When using the sous vide thing (110€ on amazon.de - feels like a ripoff) at 50°C sharp it feels like I wasn't getting any bleaching and discolorations while the brightening was working well but took a long time.

This motivated me to actually go back and revisit some other caps that I previously brightened with the UV method and never really got as bright was I wanted them to be. When using the UV method you sometimes reach a point where there are "no more bubbles" and it feels like the process has stalled. This could be due to depleted peroxide or the unability to brighten the caps any further. Or the UV light wasn't reaching the sides of the caps as well thus bleaching out to tops while the sides were still in need of some brightening.

This was no longer a concern since this temperature method will reach all parts of the caps evenly - I love it! So let's take a look at those caps. They came from another Cherry G80 OEM board - this time for Commodore.
Spoiler:
Before pictures with references. The "light" mods looks kinda bright right? And the "dark" alphas look nice and grey eh?
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Inside the water bath - special gues the F10 cap from the previous set!
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Holy fuck did I not see that coming. Look at how YELLOW the reference (TAB) mod looks now and how much darker the reference (Num0) alphas look:
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Already got another set of these keycaps lined up and in the water. Here's some pics from the current process:
Spoiler:
Before (Space bar will be the reference):
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Initially in the water with the peroxide:
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After a few hours at 50°C:
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Stop farting you ass queefers:
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Once I got these sets all to a condition I am happy with I will be doing EXTENSIVE experimenting with this sous vide robot cock exposing all kinds of ABS caps to various temperatures for an extended time. Like one hour at 40°C, again at 45°C, 50°C, 55°C and so on.

Then probably take some nasty HAD shit and put them in peroxide for a couple of hours ... maybe 3-4? ... at various temperatures and compare the results. My assumption is this reaction is temperature dependant - duuuh - and higher temperatures speed up the reaction greatly. They will obviously also fuck up your caps greatly so it would be really neat to find the lowest temperature at which this effect is reliably happening - even if it takes two days to brighten a set of precious caps. Another factor might be the level of depletion of the peroxide. Certainly at some point the peroxide will be used up. Can we use the same peroxide for more brightening at higher temperatures or is peroxide that won't react at 40°C depleted even when cooking it ;) Just got a shipment of another 20l of that stuff. Hope the BND is smart enough to find this thread of mine and understand I am not one of these YALLALALALAAL-poof dudes.

Oh and another side note. Don't get that shit on your hands. I stopped giving fucks and got so much on my hands, they're super gentle now ;)

User avatar
snacksthecat
✶✶✶✶

14 Jun 2018, 19:52

Incredibly relevant to my needs. Thanks Wodan!

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scottc

14 Jun 2018, 20:37

This is so fucking cool. Need to get my hands on a (cheapo) sous-vide!

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ScottPaladin

14 Jun 2018, 20:39

scottc wrote: This is so fucking cool. Need to get my hands on a (cheapo) sous-vide!
You should get one anyway. I'm not joking; it's the best cooking tool you can have behind a good knife and a cast iron pan. Beautiful steaks, tender brisket, and the juciest chicken you've ever eaten: all of these await you on the other side of that warm water bath.

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scottc

14 Jun 2018, 20:51

Can I also cook the steak in peroxide?

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ScottPaladin

14 Jun 2018, 21:11

scottc wrote: Can I also cook the steak in peroxide?
Albino ribeyes, here we come!

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ZedTheMan

14 Jun 2018, 23:22

Revolutionary!

This seems more convenient than making batches of retrobright the old way, and also more consistent!

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lucar

15 Jun 2018, 08:29

Hi Wodan,

I suggest You try glass marmalade cans as containers instead of ziplock bags with a 1:5 or 1:4 solution of 30% peroxide : water . In my experience pressure has some influence in the process and marmalade cans are gas tight to some extent so the peroxide solution / caps bath will stay at pressure and peroxide will deplete slower.

I think pure 30 or 40 % peroxide is too aggressive for the plastic to deal with, I would go for a lower solution.

I sunlight retrobright my caps with those glass containers and I had good results. It takes 2 or 3 hours under sunlight to get rid of the caps yellowing BUT the result in some cases might not be as even as Your method, obviously.

I did understand that temperature is a factor in the process, since as temperature rises in the glass container the retrobright process accelerates and sometimes I loose control of it (i.e. in a few minutes they go bleach).

Those glass cans are meant to be used at 100 deg Celsius so no worries of breaking them with high temperature. Do remember to install the required rubber gasket.

Image

Luca

User avatar
matt3o
-[°_°]-

15 Jun 2018, 10:45

just a quick note. sun light is not a good UV source for our purpose. Buy a good UV lamp, the result is way better than direct sunlight.

regarding the boiling thing, I'd just like to know if re-yellowing is as fast as with UV or if it's a more permanent solution.

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Wodan
ISO Advocate

15 Jun 2018, 11:03

matt3o wrote: just a quick note. sun light is not a good UV source for our purpose. Buy a good UV lamp, the result is way better than direct sunlight.

regarding the boiling thing, I'd just like to know if re-yellowing is as fast as with UV or if it's a more permanent solution.
For my UV brightening, I was using a setup with two "Desert Sun" UV bulbs

Has there been any solid investigation into the re-brightening?
I could just take a well processed batch, take some pics with a few PBT caps for reference, store them in the dark for a year and take pics again.

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lucar

15 Jun 2018, 12:20

matt3o wrote: just a quick note. sun light is not a good UV source for our purpose. Buy a good UV lamp, the result is way better than direct sunlight.

Hello Matteo,

I did try with UV lamps but either my lamps were not strong enought or the process is too slow , I gave up in favor of exposing the glass jar to direct sunlight in may/june starting from 10:00 till 13:00 local time (I live in central Italy), in bright sunny days. It takes 2 or 3 hours to have good results on caps and cases. I do full peroxide immersion for both.

As for re-jellowing, I'm maybe too new to the hobby to tell if my year old retrobrighted keyboards will ever jellow again.

With no doubts , if Wodans method works, it will be the best discovery after the wheel.

:)

Luca

codemonkeymike

15 Jun 2018, 13:10

lucar wrote: I did try with UV lamps but either my lamps were not strong enought or the process is too slow , I gave up in favor of exposing the glass jar to direct sunlight in may/june starting from 10:00 till 13:00 local time (I live in central Italy), in bright sunny days. It takes 2 or 3 hours to have good results on caps and cases. I do full peroxide immersion for both.
What kind of UV lights? Cheaper black-lights only release a little UV-a. I own a UV bulb that covers most of the UV spectrum and it makes florescent minerals pop (that is why I got it). This is an untested theory though. My second theory is that it could just be the heat of the bulb because Incandescent black-lights get really hot, like a 40w bulb produces 38w of heat.

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matt3o
-[°_°]-

15 Jun 2018, 14:46

yeah it depends on the UV lamp you have. certainly heat plays a role in it, but it's the UV that does the job. Just get better UV lamps :)

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pngu

10 Jul 2018, 13:49

Hey! I can't wait to try this on some caps. I suppose the temperature is more important than the concentration of peroxide in this, which concentration did you use?

andrewjoy

10 Jul 2018, 15:18

Be very very careful with UV lamps , certain types of UV can damage your eyes and skin in a few mins of exposure

Ascen1ty

11 Jul 2018, 01:35

pngu wrote: Hey! I can't wait to try this on some caps. I suppose the temperature is more important than the concentration of peroxide in this, which concentration did you use?
I would assume 11/12% from Wodan's post history (which is the same percentage as 8bit guy's "40 volume") - that & 12% seems to be the maximum percentage you can buy in Europe.

Yesterday, I dropped a particularly yellowed key into a 50/50 H2O2 12%/water mix (effectively 6%) & popped it out in the sun for 2 hours which gave great results... unfortunately, I now realise that all my other keycaps need doing :lol

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matt3o
-[°_°]-

14 Jul 2018, 07:55

130 VOL (35%) is relatively common and used for bleaching wood. I always used that for retrobright

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Wodan
ISO Advocate

14 Jul 2018, 09:38

I might try the nasty 35% stuff ...

Available here
http://disinfection-shop.com/shop/desin ... diosol-35/

User avatar
pngu

14 Jul 2018, 13:20

Ah, I already ordered 5 liters of the 12% stuff, I figured higher percentages weren't easily obtainable. And sweet Jesus, that 35% stuff is pricy wew.

Ascen1ty

28 Jul 2018, 23:32

matt3o wrote: 130 VOL (35%) is relatively common and used for bleaching wood. I always used that for retrobright
Wodan wrote: I might try the nasty 35% stuff ...

Available here
http://disinfection-shop.com/shop/desin ... diosol-35/
Ahh, unfortunately you need a license to purchase over 12% in the UK :lol:

Pvt_Ryan100

01 Jan 2019, 21:47

Just to add some feedback about larger items such as computer cases. I have a brewpi setup https://www.brewpi.com/fridge-hacking-guide/

and used it to restore an amiga 500 case.
BP1.png
BP1.png (62.87 KiB) Viewed 2507 times
Amiga 500 p1.jpg
Amiga 500 p1.jpg (81.21 KiB) Viewed 2507 times
Finished.jpg
Finished.jpg (313.37 KiB) Viewed 2507 times
Hope this helps anyone with larger items.

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Hypersphere

02 Jan 2019, 15:58

@Pvt_Ryan100: Splendid guide! Thanks!

@Wodan: Could you please confirm the final hydrogen peroxide concentration that you recommend? Thanks!

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matt3o
-[°_°]-

02 Jan 2019, 17:55

in the original video they use 40% peroxide. I always used 35% with good result and no damage.

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Wodan
ISO Advocate

02 Jan 2019, 19:29

Hypersphere wrote: @Pvt_Ryan100: Splendid guide! Thanks!

@Wodan: Could you please confirm the final hydrogen peroxide concentration that you recommend? Thanks!
I use 11% peroxide which seems to be the limit for personal use in Germany

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Hypersphere

02 Jan 2019, 19:49

Wodan wrote:
Hypersphere wrote: @Pvt_Ryan100: Splendid guide! Thanks!

@Wodan: Could you please confirm the final hydrogen peroxide concentration that you recommend? Thanks!
I use 11% peroxide which seems to be the limit for personal use in Germany
Thanks, Wodan! Here in the US, it appears that you can buy 35% from a retail package store, but 12% seems to be our limit for shipping.

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stratokaster

02 Jan 2019, 20:47

I wonder if it's possible to use sodium percarbonate (which releases hydrogen peroxide when mixed with water) to retrobright things? It's widely used as a laundry whitener, it's easy to buy and easier to store than liquid hydrogen peroxide.

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Hypersphere

02 Jan 2019, 22:12

stratokaster wrote: I wonder if it's possible to use sodium percarbonate (which releases hydrogen peroxide when mixed with water) to retrobright things? It's widely used as a laundry whitener, it's easy to buy and easier to store than liquid hydrogen peroxide.
Assuming you had pure sodium percarbonate, whose formula can be written as Na2CO3*1.5(H2O2), a mole of this decomposes in water to yield 1.5 moles of H2O2. The solubility of sodium percarbonate is around 150 g/l at room temperature. The formula weight of sodium percarbonate is 157 g/mole, so a saturated solution would contain 0.9554 mole/l, which would generate about 1.43 moles of H2O2. This would which be about 48.6 g/1000 ml or 4.86%, but I do not know the solubility of H2O2 in the presence of the sodium carbonate that would be formed. In any event, it looks as though if you want 12% or more H2O2 in water, it would be best to buy the hydrogen peroxide solution.

However, someone should check my arithmetic.

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