NMS keyboard well know keys yellowing issue: maybe a fix?

Expert (120)

05-04-2014, 18:40

I bought a very nice Philips NMS 8250 MSX2 Computer today with a case as good as new without any scratches whatsoever, the drive is working etc! The keyboard is quite ok too but has the well know yellowing issue:

Pic keyboard

Now, I found this blog about fixing this yellowing issue on vintage computers with peroxide and sunshine.
A few days ago, I bought a bottle of peroxide 12% and have tried it on a Commodore 64c: it's really working!

I just wonder if it will work too on the NMS 8250 keyboard: it seems only one row is still ok, the rest is quite yellow which is actually strange (and I've seen that on other NMS keyboards too).

Any thoughts?

By mais1976

Master (172)

05-04-2014, 19:16

I used it on a toshiba, I guess it should work on a NMS keyboard too.

http://www.msx.org/forum/msx-talk/hardware/cleaning-keys?page=0

By Denus

Expert (120)

05-04-2014, 21:10

Seems to be the same thing:
“The problem was finally cracked in late July 2008 with a mixture of hydrogen peroxide, a small amount of an “Oxy” laundry booster as a catalyst and a UV lamp"

I got a hair product with 12% hydrogen peroxide and some perfume as a bonus
The UV lamp can be replaced by the huge bulb we call "the sun".

Anyway: glad you confirmed it could work on the key's too, I will definitely try it.

By Retrofan

Paragon (1339)

21-09-2014, 10:56

@Denus: great! Do you have pictures how it looks right now? Any difficulties?

By Daemos

Prophet (2070)

21-09-2014, 16:06

Denus: Be aware you are not only oxidising the yellow color. There is a big chance you are oxidising the plastic as well. Using UV as an extra creates even more powerfull free radicals. You may run into new problems such as the becomming brittle of the keys. There are milder oxidisers on the market that may get you the same results. Allready tried bleach?

By Retrofan

Paragon (1339)

21-09-2014, 16:42

@Daemos: do you have a link to the product? (bleach) I'm in NL.

By Daemos

Prophet (2070)

21-09-2014, 19:51

Bleach is what is used to clean the toilets so just go to the supermarkt and vind Dikke Bleek. Try to find the cheapest one. Just use the pure stuff without extra water and see what happens after lets say 6 hours.

Another tryout could be varnish oxy gell. I don't know if they still sell that stuff. It may be even milder than bleach.

By AndreV

Master (232)

26-08-2019, 19:31

Tried today to turn my yellow keys on my NMS 8250 keyboard, grey again. little bit of warm water and two small botttles of waterstofperoxide/Hydrogen peroxide 3% from kruitvat and little bit of vanish in a small plastic container, whole day in the sun, actually i didn't think it would work but it turns out ferry, ferry nice. grey keys again!

By Grauw

Ascended (10772)

26-08-2019, 19:30

Got some nice before / after pics?

By AndreV

Master (232)

26-08-2019, 19:34

sorry no, but you see whole difference. din't expected that because of the low percentage hydroperoxide

By AndreV

Master (232)

26-08-2019, 20:00

https://ibb.co/m5Bt5Tv

upper keyboard was treated and was far more yellow than the otherone