Here's something from me!
Hydrogen peroxide at 25%, I always stay for 12 hours in the BlueBox at 55 degrees!
It was literally orange, not yellow! :)

https://eab.abime.net/attachment.php...1&d=1668794123

https://eab.abime.net/attachment.php...1&d=1668791096

https://eab.abime.net/attachment.php...1&d=1668794099

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https://eab.abime.net/attachment.php...1&d=1668791096

https://eab.abime.net/attachment.php...1&d=1668791096

https://eab.abime.net/attachment.php...1&d=1668791096

https://eab.abime.net/attachment.php...1&d=1668791096

Why is the remove of the yellowing such a big deal?
35+ year old plastic products will have a natural bit of yellowing i think?

Because in our heads it is still 1992 and our Amigas were still crispy white. :D

The most accurate answer! :):great

It looks bad? Like universally bad :)

Anyone made "retro bright" and is still not yellowed after at least 2 or 3 years ?

I have some devices that were treated in 2013, and while they have reyellowed a bit, they still look reasonably fine. Whiter than before the treatment for sure.

I think it depends on how quickly the treatment is completed. If you use a very concentrated solution and it was completed after 20 mins, then perhaps it is just a very slim outer layer which has been whitened and then it will quickly reyellow from underneath (just my theory). I used 12% peroxide and diluted it down to around 3% so the reaction took quite a bit longer. Some people used undiluted 30% which you can't even get around here.

Great to hear that. I actually admire this work and procedure so it is great to hear it pays off.

The best results I have actually had just using the sun - no peroxide or anything. Just clean the part well and put it in the sun for a month or two until it looks good. I had a few experiences with white streaks using peroxide (mainly when experimenting with stronger solutions), but the sun-only method always served me well, although it does require some patience. :)

Not sure if it is less prone to reyellowing, but I had parts I did that way about 4-5 years ago, and they still look quite good to this day. One of them (a C64C) was very bad and had white blemishes from stickers where it was less yellowed but it all evened out and those blemishes have not reappeared.

My UVBox is called the UVNator


https://youtu.be/srUqM2MSb90

Have a watch, its fun, and if you want to see the results from it. Watch this...

https://youtu.be/VNW3fdr9srU

It certainly works. The concentration of peroxide is a bit of a peice of string, because you HAVE to add water to it, to immerse your items. My rule of thumb is, it should be near 6% ideally, and you should have some kind of tingling on the skin when you put your hands in it. Of course you should wash your hands afterwards, as well as the times removed from it of course.

And as to WHY, well, Im sorry but I come from a time when smoking was rife, and I kind of associate that orangy brown colour with nicotine accumulation on smokers fingers. Ergh... not good...

I want my Amiga's to look pristine, and orange they were not....

My UV box looks similar but with one 150w UV light. This turned out to not be optimal because it gets so hot that it can't even be touched. I thought it would melt the plastic but it does not. It now has a permanent fan on it to cool it down to acceptable levels. It is extremely effective though and I can hear the bubbling going on inside.

https://www.amazon.de/dp/B0B5H5JZFS?...roduct_details

https://grandis.nu/images/Craplinks/uvbox.jpg

Its a standard IKEA storage container with a square hole cut out at the top for the light. The inside is just covered with aluminum tape that reflects well. At first I was going to use mirrors but I read that the glass in mirrors absorbs most of the UV so that is not good to use.
The UV light is just taped with blue tape that is easy to remove afterwards.. mostly just to keep it in place. When not used, the light and fan etc are stored inside the box and stacks nicely with my other IKEA storage boxes.

https://www.biltema.se/en-se/constru...ape-2000017580

I use undiluted 12%. You can buy 3 x 5 liter for less than $80 so I don't care to dilute it. Plus, it can be reused a few times. So far I've only used the first 5 liter container and reused it 3 times without issue. 5 liters is enough to cover everything I put in it so far. Might have to dilute it for larger cases I guess..
I wear protective glasses and plastic gloves when handing it. You can really feel it on your skin after a few seconds so be careful. Wont hurt your skin that bad but do not get it in your eyes.

https://grandis.nu/images/Craplinks/peroxide.jpg
https://www.stadshop.se/p/stadkem/sa...xid-12-5l.html

I did a lot of retrobrighting in ~2012 and some of my images and progress is in this thread. It all went back to yellow after a year or two so I stopped doing it and accepted the yellow, but I want to try it again so... here I am =)

Edit: When disposing of the hydrogen peroxide, I poured some of it it in the shower. It started bubbling like crazy between the tiles and area between them now looks brand new. Heh

Made a test today since it was sunny and a clear sky but not very warm. Not quite there but I'll give it another go. Forgot to remove or cover the sticker though but I think I can fix that bleached red.



http://www.sjolin.eu/4kfrontcomposite.jpg

Sun alone or with peroxide?

Forgot to mention that. Peroxide cream and wrapped in plastic wrap.

The colors on the A4000 badge look a little washed now...

Yes, I mentioned that I forgot to remove or cover it. It's mostly the red bit that's affected but I can fix that.

Yeah! - You can by them for less than a pint of beer here in the UK & eBay is your best friend. :D

But really....

That's a cracking result above.... Truly Amazing! :great

It's not perfect. There's a bit of yellower patches on the top as shown in the bottom of the picture.

And the bottom is a lot whiter than the rest so I hope I can get it even better. Don't think the sun is quite strong enough so gonna wait a few weeks until the sun is at it's highest and have another go at it.

I've seen some people getting fairly good results with peroxide and an oven. Question is what temperature to use, wouldn't want stuff to melt. .)