Can you retrobright using only the sun?

[@morantaylor]

The yellowing is caused by some frequencies of sunlight being filtered out indoors. Outside the full spectrum light bleaches the plastic. There was a you tube video a few years ago where a chemist explained the process.

[@networkg]

Jon, thank you for doing this video. Just last week I watched a very convoluted process where the KZbinr explained in great detail why hydrogen peroxide is necessary. I posted that I have got great results with just the sun and that here closer to the equator, it works great. The response was to call me out as being illogical and wrong. Nice to have vindication.

[@jonobst]

You are very welcome :)

[@andycraig7734]

I didn't want to mess with chemicals or risk squirrels chewing on the plastic outside, so a very yellow Commodore 64c was subjected to strong UVA (black lights) indoors. I found they greatly removed the extreme yellow for awhile, but then stopped getting better before the job was done. It ended up with about 2/3rds of the bad yellowing gone. Improved, but not the factory white of the Conmodore 64c.

[@andycraig7734]

Details- 100watt x2 lights (very bright!). 32hrs it was greatly improved. 45hrs a little better but slowed down the improvement. +24 more hours and I saw no change. Not quite as nifty as I'd hoped, but I got the lights on the cheap and felt it was no risk of rain/squirrels outside and no chemicals and this insanely yellow computer became tolerably, slightly yellow. 🙂

[@IkesVintageTech]

Living in Hawaii for years I've seen the sun do some real damage on plastics. They get whiter but also brittle. I'm currently retro-brighting a Molar Mac using the vapor method and am very impressed with the results and ease of cleanup. At least using this method it's only out there for days and not months that would do the real damage.

[@insanelydigitalvids]

When you "Think Different" about retrobright and it work beautifully! 😎

[@crunchyfrog555]

I do this all the time. Even here in Britain. Granted you have to wait longer to get results but for me I quite like it for a number of reasons (as I have a lot of computers and consoles to maintain). Firstly, I find it gives a more even finish. The sheer fact that sitting it in the sun so it gets a fairly even dose of sunlight makes it better. Plus, if you're disabled like me and are against too much faffing around with stuff, then simply leaving it alone and letting nature do it's thing is beneficial. Also, as plastics tend to get brittle over time as they degrade, I find messing with them less so you don't invite problems is a benefit too. In short, it's simple and the only thing that's worse is the time taken. But if you've got time to leave it's easy.

[@jonobst]

Yes, especially the Spindler era plastics - such a shame a majority of those machines are basically crumbling to pieces. Having heard rumors about summer being more like rainy season in Britain, I sympathize with you. ...and yes I've seen a lot of streaky plastics from people doing the peroxide cream incorrectly.

[@Retroman8000]

I use tinfoil or a mirror under the item. Use 2 or 4 items to support it above it, i use 4 inch high rocks not exactly lol then I give it a while day in the middle of the yard, sun up to sun down and it works pretty good

[@Kill3rT0fuuu]

I can only find aluminum foil, does it work the same?

[@jonobst]

Probably better than tinfoil!

[@timkaragias213]

Nice! I have a few yellowed electronics and some intense central Texas sun to give this a try!

[@jonobst]

Good luck!

[@bluephreakr]

I think the science behind this is the UV light _blocked by a glass window_ only allows -UVC- UVA to enter in a setting that has exposure to the sun, which is why certain plastics degrade in appearance by becoming yellowed under certain conditions where light loses some of its properties due to the filtering of specific wavelengths and plastic reacting poorly to that. Putting it out in full-spectrum lighting as afforded by the sun then reverses this damage by bleaching the plastic. Bones exhibit this same property as well; under storage, they may yellow across time but found in a desert setting, with the flesh consumed by all of nature and abraded by wind-swept sand, exposed bones can look surprisingly white.

[@jonobst]

Fascinating, and yeah that does make sense!

[@tenminutetokyo2643]

Yes it does work, it just takes longer.

[@sobertillnoon]

Windows block uvb and uvc wavelengths. Maybe the yellowing is caused only by UVA ones?

[@Draciel360]

I would be curious to see how effective a thrown together "Suntan mirror" would work to help get coverage in and around keys; of course being careful to avoid stray rays or anything that might cause a fire

[@jonobst]

Just guessing here, but I would think that the reflected UV radiation would be slightly less intense as the mirrors' surfaces would absorb a tiny amount -- but probably do the job anyway. Good thought to try next time!

[@Retroman8000]

Of course

[@chubbyadler3276]

I'm surprised that it does reduce the yellowing, though I also wonder what else the sun is doing to the plastic. I know ABS tends to not hold up very well to outdoor conditions and direct sun.

[@jonobst]

I was also surprised at this. The plastic doesn't feel any different now than it did before, so I don't thiiiiink there was any damage done.

[@swolfington]

This is a cool experiment with very interesting results, but I'm worried about how much damage the UV is causing the plastic.. though I guess that's an issue with traditional retro-briting as well. Also, just FYI, those two keyboards you used are Appledesign keyboards, not Apple Extended Keyboard II's . AEK II's use mechanical switches are are pretty nice keyboards to use even today. and while there are probably still tons of them out there, they are definitely not in the dime a dozen catagory, at least if you want to buy one.

[@jonobst]

I was waiting for this comment - I have examples of all three and got confused by Apple's naming schemes when recording! Yeah, the plastic didn't seem to take any further damage at this point, but I guess just waiting it out a bit and seeing if one half is more brittle than the other in a year, or two years, etc.

[@Jeritude]

I have tried it and it works temporarily but turns yellow again pretty fast

[@crunchyfrog555]

That is nothing to do with the sunlight but rather the plastic - you would likely have very similar results with peroxide. The reality is that the bromide leeches out over time and it doesn't stop. For example, I have few Gamecubes that I find amusing because the faceplates on these vary wildly. I live in England, so sunlight isn't that great, but they are permanently kept away from sunlight in a closed room and always have been. Yet one is still quite white/grey, another is REALLY brown, and another is half and half - the left side has browned somewhat and the right side is greyish. It's all to show that bromide and plasticity is weird. ALL plastics break down, offgas and do weird things as they aren't permanently stable. So even though these three Gamecubes I gave examples of are exactly the same, have been treated the same all their lives, and vary so diffierently demonstrates how things can vary. The trick is to not assume causes, but find out from evidence. And from my evidence, I've seen that the biggest cause of browning and returning browning is completely beyond your control.

[@jonobst]

I am planning on posting an update in ... a year? two years? who knows, I am going to hang on to this keyboard for sure as an example though!

[@mk500]

@@jonobstPlease do; that would be great data. I also have similar great results with sun-brightening over the last year or so. I’m curious how long it will last.

[@johnbrandon334]

​@@jonobst how is the keyboard doing now, about 6 months later?