Advice on retrobrighting

User avatar
TNT

08 Dec 2020, 17:55

Hey guys,

I recently managed to get ahold of a Data General 6348-A terminal keyboard. (The one in this blogpost: https://kuritakey.zone/data-general-d63 ... -keyboard/)

However, mine is in considerably worse shape compared to the one shown in shallot's blog. Case and caps desperately need some retrobrighting. My camera doesn't do a very good job at picking this up but trust me, it's really bad. See the backside of the board's feet on top for reference.

Since I'm not a big fan of the brightening approach with cream I've always just worked with liquid peroxide and achieved some pretty good results that way. Plus I don't have a UV-lamp. This board however has one of those foil legend-strips above the top row (comparable to those on FK 2001s, but not removable). Unfortunately, it's glued in place, and removing it could possibly damage it (visible crinkles on its surface, adhesive layer ripped of uneven which might lead to tears, etc.).

That's where my question comes in:
Do you think it's a bad idea to submerge the case as it is, so with the strip still on in H2O2? I definitely don't want to damage it. The sticker is peeling off a little on one edge too, so submerging it will probably only worsen that, right? Has anyone here experienced something like this before?

On its inside, it has brass inlets as counter threads for the screws that hold the board together. Since metals normally don't go well together with peroxide I'm a little bit concerned about those as well.

What do you suggest?
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User avatar
matt3o
-[°_°]-

08 Dec 2020, 18:38

you may try to remove the sticker with limonene or some light solvent but it's a long and tedious process. Your "luck" is that it is starting to peel off already so you can start from there. if you don't use strong peroxide and you don't brush it the sticker might even survive the retrobrighting but I would not risk it

User avatar
jsheradin

08 Dec 2020, 19:02

Depending on the adhesive, you might have some luck with hot air and a thin plastic blade. If you absolutely can't remove it, I'd cover it with some kapton tape and do the peroxide bath as normal.

There's tons of places that do small batch vinyl stickers. If you can manage to get it off reasonably undamaged you could scan it, tidy it up in photoshop, and have a few reproduction ones printed.

User avatar
E3E

08 Dec 2020, 19:22

You do not need to remove it. It won't damage the label. I've retrobrighted keyboards for years now, and these labels are often made from some kind of Mylar, PET film, I'd guess. They won't be affected by RB.

Consequently, if the label HAS yellowed, it's done for. You can't restore it using any method I've seen. I'm not sure what causes label yellowing. I'd guess heat.

User avatar
matt3o
-[°_°]-

08 Dec 2020, 20:05

oh yeah if it's made of plastic, just go for it. I assumed it was paper/cardboard

User avatar
TNT

08 Dec 2020, 22:57

Nice, thank you guys very much for the quick responses! That makes it tons easier for me. Yeah, should have made it clearer that it's plastic. And it hasn't yellowed or degraded in any way.

Here in Germany a 12% solution is the highest concentration you can get, so it's not that strong either. But maybe I should get myself a UV-lamp since the sun doesn't do the job rn. It probably isn't too healthy for the plastic to sit in a peroxide bath for too long?

What about the brass threads tho?

User avatar
jsheradin

09 Dec 2020, 05:48

The plastic will have long disintegrated before the brass even tarnishes. Peroxide baths are not particularly good for plastic but the difference is minimal. If the color bothers you it's well worth going for it as the KB wouldn't be doing much else anyways.

Keep shadows and uneven exposure in mind if using a UV lamp. I'd recommend keeping a few meters between the lamp and peroxide bath so you can control the colors better over a longer time.

User avatar
matt3o
-[°_°]-

09 Dec 2020, 09:01

TNT wrote:
08 Dec 2020, 22:57
Here in Germany a 12% solution is the highest concentration you can get
check ebay on other European countries. 35% peroxide is pretty common and cheap here (Italy). It is used to bleach wood (check your local hardware/paint/carpentry stores they might have it). 35% is pretty strong though, you may want to tone it down a little.

User avatar
TNT

09 Dec 2020, 10:06

matt3o wrote:
09 Dec 2020, 09:01
TNT wrote:
08 Dec 2020, 22:57
Here in Germany a 12% solution is the highest concentration you can get
check eBay on other European countries. 35% peroxide is pretty common and cheap here (Italy). It is used to bleach wood (check your local hardware/paint/carpentry stores they might have it). 35% is pretty strong though, you may want to tone it down a little.
As far as I know, it's not legal to possess here. Don't want to end up on some kind of list. 12% and a good amount of patience were all I needed so far ;)

I'm still concerned about the brass tho. As an oxidation agent, it was recorded that peroxide reacts with metals rather quickly. I have some brass screws lying around somewhere on which I can test it myself but I think I'm going to try it with the salon cream approach on this one. Thank you all for your advice and I'll keep you updated.

User avatar
vvp

09 Dec 2020, 22:54

35% peroxide can be bought in Slovakia in shops selling paint, thinners etc
So there are at least two EU countries where it can be bought easily.

User avatar
hellothere

10 Dec 2020, 23:44

A definite "FWIW": I did a test regarding just using direct sunlight to "retr0bright." It did work, but it made my keyboard only a couple shades lighter. It's a no-cost approach and your keyboard doesn't look too far on the yellow side, so it might be ideal for you.

I generally use the 40, 50, or 60V hair cream stuff, using whichever is in stock on Amazon and is the cheapest for a gallon (1.1 Pascals in metric). It works extremely well for keys, but it requires a lot of supervision for the case, which was learned over many applications.

Oh. I also did have one of the LED light stickers come off my keyboard that I retr0brighted. It also ate the Apple logo, too, on a different keyboard. But I'll go with E3E and say that the TWO keyboards I had that had those plastic insert things didn't have a problem with retr0bright. Do watch for the labels on the back. Retr0bright will definitely make those come off.

User avatar
TNT

10 Jan 2021, 14:47

Okay. I used cream oxidizer (12%, so it took quite some time). Turned out very well IMO:
WhatsApp Image 2021-01-10 at 13.45.22.jpeg
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WhatsApp Image 2021-01-10 at 13.44.57.jpeg (107.42 KiB) Viewed 2472 times
For comparison a Focus Fk-5001. Quality is garbage, as usual...

User avatar
TNT

10 Jan 2021, 14:48

The keyboard is not as pale as it seems in those pictures. Rather a type of pearl- or cream-white.

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