Cleaning/retrobrighting old computers (Dragon 32 mini project)

[Morkin]

I've been reading a little bit about this - there seem to be a few different methods suggested for revitalising old computers/cases. The problem I've found is that I've never been too sure exactly what products are available in the UK (and where to get them from).

Anyway I thought I'd bite the bullet this weekend as I had a free day and I've heard sunlight can help (it was approximately 8,291 degrees in Bristol today). So I thought I'd finally have a go at cleaning my Dragon 32.

The case was fairly yellowed:



Once I opened it up I discovered a fair amount of gunk inside the case and keyboard section:



Anyway, I gave it a good old clean with some water, washing up liquid, toothbrush & cotton buds and it looks a bit nicer now.

For the brightening the only product I'd bought was a 5L canister of Hydrogen Peroxide. I was a bit scared of causing damage so I thought I'd play it ultra safe and got only 3% concentration.

As it turns out, I had to further dilute it so the case could be fully submerged in the plastic box it rested in. I left it out on the patio in the sun for a couple of hours.

One slightly annoying thing was that as I wasn't keen to remove the sticker so I though I'd be clever and tried to protect it with a strip of paper/tape combo. It failed miserably and came off pretty quickly...

I have to admit as the solution was so ridiculously ultra-diluted by this point I didn't expect anything, but it looks as if it made a bit of a difference:



You can see from the left and right yellow marks by the ridges on the top where I had to weigh the sides down so it was submerged in the liquid. I think next time I'll have to use a different method - maybe weights attached with string? Dunno.

Also when I compared it with the bottom case section the difference is noticeable:



So I was fairly pleased that there's potential to have another go.

Has anyone tried this with any of their computers? Any tips with dealing with stickers, labels etc?

I think I'll give it another go at some point, though I might have to wait till the next sunny day in England, so it might be a while. Perhaps I might have to keep moving it around the patio a bit more to evenly expose bits to the sun.

[Morkin]

...This week in Bristol, I thought I'd make use of this abundance of UV we seem to be getting...

This time no treatment, no peroxide, I literally just left the case out in the sun on a garden chair on the patio a few times this week.

Figured I had nothing to lose since we're going through a mini heatwave here at the moment. Well, as far as the UK is concerned, 30+ degrees is a heatwave, it gives us a solid few hours of British weather-based chit chat with neighbours etc.

Surprising what a difference a bit of sunlight can make (top = previous, bottom = new).



To my eye it's definitely a bit brighter. But the best bit it that it involved very little effort

I did read that leaving some plastic cases out in the sun might damage them? Though this seems to be fine.

Anyone else been using the sun to bleach some of their yellowed retro cases?

[llewelyn]

Looks pretty effective BUT be aware that UV does no good to most resins, some its disastrous on such as epoxy resins. I would be wary of embrittlement which could lead to cracks or even distortion of certain parts. Still think its an ingenious solution though but if I was to try this I'd hedge my bets by giving it a wipe over afterwards with Armor All.

[akeley]

I know nothing about this subject but saw this vid being discussed on some other forum:

https://youtu.be/YPl356YKcVs

[bluespikey]

That's a lovey read, thank you. I'm surprised that buying 5L of Hydrogen Peroxide didn't summon the anti terrorism police. Try explaining that you were using it to clean a Dragon computer...

[Morkin]

Looks pretty effective BUT be aware that UV does no good to most resins, some its disastrous on such as epoxy resins. I would be wary of embrittlement which could lead to cracks or even distortion of certain parts. Still think its an ingenious solution though but if I was to try this I'd hedge my bets by giving it a wipe over afterwards with Armor All.

I know nothing about this subject but saw this vid being discussed on some other forum:

I haven't heard of Armor All, but yes, I guess that's why I was a bit unsure as I'm quite new to this - I'd seen a few different suggestions and warnings about methods but that video sounds like a quite comprehensive (and scientific) investigation.

I did skip some of the technical bits about what it's doing (chemistry was never one of my strengths) but near the end of that vid there's a bit about 'sunbrite-ing'. It sounds as if the type of plastic and amount of sunlight and heat it's been exposed to should be fine for what I've done so far.

I was a bit worried about over-lightening it because I couldn't quite remember what colour a Dragon 32 SHOULD be. Photos of 80s computers seem to vary in colour saturation on the internet, so I'm not going to do any more with the colour (it's probably a bit yellower to the eye compared to my photo).

I did also watch another video that made a good point - these machines are close to 40 years old now, so a bit of yellowing gives them a bit of character compared to a lot of the shiny new tech we're used to... If I wanted a shiny new retro machine I'd probably buy a Next..

That's a lovey read, thank you. I'm surprised that buying 5L of Hydrogen Peroxide didn't summon the anti terrorism police. Try explaining that you were using it to clean a Dragon computer...

Errr - I bought some more so I've got another 10L of the stuff

Apparently at 3% it's pretty dilute though, I might just use it for cleaning the bathroom...

[MrClump]

I was a bit worried about over-lightening it because I couldn't quite remember what colour a Dragon 32 SHOULD be. Photos of 80s computers seem to vary in colour saturation on the internet, so I'm not going to do any more with the colour (it's probably a bit yellower to the eye compared to my photo).

I’ve done a fair bit of retrobrighting and in my experience you can get a pretty good idea of what the original colour was by looking at the inside of the case as they are rarely yellowed. A good example is the Amiga 1200, the keycaps on those were white and they yellow something awful, but they are pretty much always still pearly white on the inside.

[Morkin]

I’ve done a fair bit of retrobrighting and in my experience you can get a pretty good idea of what the original colour was by looking at the inside of the case as they are rarely yellowed. A good example is the Amiga 1200, the keycaps on those were white and they yellow something awful, but they are pretty much always still pearly white on the inside.

I guess that's something that'd be fairly obvious to most but I didn't think of it..

Most of the vids I watched seem to be US ones, they always seem to be messing with C64s and Miggys...

[MrClump]

I guess that's something that'd be fairly obvious to most but I didn't think of it..

I wouldn't say it was that obvious, I only noticed it for the first time when I was doing an Amiga 1200 because I knew the keycaps were meant to be pearly white and they were on the inside.

[patters]

Most people use the liquid peroxide because the cream peroxide can result in a kind of streaked, almost bone-like appearance. I had a Japanese Sega Saturn do this. Well not quite - the console brightened perfectly, but the disc lid streaked. I had to use cream as the case was so big. Some say there may be an interaction with oils from hand prints etc., or even that it's just pot luck.

Also, it's common for the brightened plastic to end up lighter than the original colour. It happened to my GameCube front panel. And there's no way back unfortunately. It's kind of put me off doing it any more. I had reasonable results doing a bunch of my childhood Lego (whites go yellow and grey gets a bit greenish), but you can definitely tell the material becomes more brittle.

Interestingly there was one yellowed Lego model that was built when I retrobrighted which I missed, and that one has just been exposed in a bright room for about a year and it seems to have brightened up fine. Some YouTubers have also noticed this phenomenon - that it almost seems that an absence of UV causes the discolouration. Interestingly, I live in a fairly new house and the modern gloss paints used for skirting boards seem to have yellowed horribly in the rooms where there is no UV exposure at all (e.g. understairs cupboard), whereas rooms with windows are fine. Areas obscured by furniture are similarly discoloured.

[Morkin]

That's unfortunate... Because I was working from home I could go and check on it, rotate it etc. It's still not the same colour as the case inside (as suggested by [mention]MrClump[/mention] but it'll do.

One mistake I made when leaving the case outside was leaving the rubber feet on it - they'd heated up and become slightly 'melt-y', so when I brought it back in and put it on a table it practically stuck to it..!



Am happy with the 'brite-ing' but unfortunately it still has a couple of issues.

Firstly, I can get a TV picture like in the pic but only briefly; the picture keeps cutting out and coming back on every few seconds. I was using a compatible SCART cable that I got ages ago, I think from Retro Computer Shack off eBay, but I'm fairly sure that used to work OK.

Secondly (slightly more of a problem), a few of the keys are 'sticky' and stick down when pressed. Having fully cleaned it out I can tell it's not gunk as the spring mechanism works fine, but I noticed a few of the small plastic squares the the keys go into seem to have slightly split, so it may be that the key is getting stuck there. Not sure what the solution to that one unfortunately..! (Apart from use joysticks... )

[Sparky]

Probably a dumb question, but does retrobrighting just make the colour lighter or does it restore it to its original colour?

[Sol_HSA]

Probably a dumb question, but does retrobrighting just make the colour lighter or does it restore it to its original colour?

Based on tons of retrobrighting YouTube videos, it restores the original color, if the material can handle the process (which it usually can).

The innards of the cases retain the original color, so it can be compared.