Removing yellowing from Amigas with peroxide

[T_hairy_bootson]

Originally Posted by Eclipse

I've heard that using aluminium powder with Iron oxide (rust) powder and heating it does wonders for Atari ST's.

Funny I've heard the same thing about petrol and matches with Atari STs

[Merlin]

Yeah, about 2 parts aluminium dust to one part iron oxide powder should make an Atari ST really fly......about 15,000 MPH if memory serves.....

[zipper]

Don't know about flying, but easily reach up to 2500 °C temperature

[Eclipse]

Originally Posted by zipper

Don't know about flying, but easily reach up to 2500 °C temperature

Optimal operating temperature I'd say.

[Charlie]

This thread is proving an excellent read.

Just one question: Does Retr0Bi(r)te work on teeth?

[Eclipse]

Originally Posted by Charlie

This thread is proving an excellent read.

Just one question: Does Zetr0Bi(r)te work on teeth?

[Merlin]

I definitely wouldn't try it on teeth, however, the chemical concept is similar to some of the UV activated tooth bleaching treatments used by dentists.

For use on the body as an antiseptic on open wounds or in the mouth, I've not seen stronger than 6% peroxide used.

[Antiriad]

Gentleman I salute your fine work!

[Amiga1992]

What the fuck?!?!

The EAB Science Magic Team strikes a punch right into yellowing's balls!

This is so incredible! I can't wait to try it in my old computers (like my first computer, my beloved C128 which I still treasure)

More than 3 cheers for this board, that keeps blurting out magnificient efforts in restoring and conserving our old computer hardware.


EAB rocks!

Originally Posted by Zetr0

you could also have "Industrial Strength Retr0-Brite" for those stubborn bromide chains

Or for military spec A2000s

[Merlin]

@ Akira

Wait until you see the test I have going on at the moment, involving a 'breadbox' Commodore 64 that I got from jimbob005 from Amibay......

I have a test in progress involving a 1985 'breadbox' Commodore 64 that is browner than George Hamilton / Dale Winton / David Dickenson / insert overtanned celebrity here.

My mixture is:-

1 pint 35% H2O2
1 teaspoonful xanthan gum (Kelzan D to be precise)
1/2 teaspoonful 'Vanish Oxy Action Plus'
1 teaspoonful glycerine

I dispersed the gum in the glycerine and peroxide using a Braun stick food blender. I let the mixture rest for an hour so that the gum could soak in. This made a thick mixture with a few lumps but not that many after one hour and it looked like wallpaper paste.

I then activated the mix by stirring in the 'Oxy', brushed on a thick coat of the mixture and stuck it under a UV lamp. The mix stuck to vertical surfaces but as it foamed up it dripped. I thought it might, so used a cat litter tray to catch any drips.

I am taking pictures before, at 2 hour intervals during, and after, so that some yardsticks will be in place as to how long severe yellowing takes to reverse. I am only doing half so the 'before' and 'after' difference should be really striking.

I'm 2 hours in tonight and I should be finished tomorrow, stay tuned.....

[pkillo]

You guys deserve congratulations on having developed this technique. The gel preparation has great potential.

to the serious chemistry that's already gone into this

I'm a bit wary of trying this at home, though, at least not without some more information. I would need to work indoors here unless I got lucky enough to have sunshine coincide with a weekend, and I would like to know if there are chemicals in the 'Vanish Oxy Action Plus' other than the TAED which will react under the conditions described in the experiment, and if any of the reactions involved will produce a gaseous output when the 'Oxy' is stirred into the paste. I do not have a fume hood, and the fan over my stove is pitiful, so I can't afford to take any chances on that.

Besides that, I'm curious as to whether anyone has a data sheet on one (or better, all) of the UVA lamps (blacklights) used in the process. The homepage linked to [Maplin] a while back doesn't have links to anything with real information. I'm making a guess that there's probably a particular spectrum within the UVA output of a black light that the gel responds to most strongly, and if one could compare the output of the various lamps that have been tried and chart the results after different time intervals under each lamp, it should be possible to figure out which lamp types work the best, thus allowing people to minimize the use of the lamps. These lamps are fairly harmless but it makes sense to use these bulbs for as short a period of time as will produce the desired results, given that some of them (the currency lamps esp.) will cause health problems given enough exposure.

I want to actually use this process soon, on a 2000 bezel I'm expecting, but I need more info, please.

[Merlin]

Okay, let's take this one piece at a time.....

The 'Oxy' will create gas as the TAED in it reacts with the hydrogen peroxide; it is a catalyst and breaks down the peroxide. There are also perborates and percarbonates present which are also catalysed into producing peroxides.

Don't worry, the gas output is very slow and not likely to produce a hazard in the quantities used. You won't blow the house up or anything like that. I am a former industrial chemist and currently a Safety Manager, I would not release an inherently unsafe process onto the masses, the liability would be mind-boggling if I did, so rest easy on that score; the normal precautions in handing chemicals apply - gloves and eye protection.

We are only interested in a small area of the UV spectrum around 620-650 wave numbers or thereabouts, because that's the wavelength that causes the bromine bonds to vibrate and break. I've used a standard filament UV bulb and an energy saving version and I can't tell the difference in how they affect the process, apart from the fact that the energy saving version produces less visible light. My guess is the energy saving compact fluorescent bulb is better than the filament type.

The whole point of making this into a gel version is that you use a lot less of the chemicals to get the same effect; you don't need a tankful of liquid when half a pint of gel painted on a surface will do. Less chemicals = more safety in my book, it's about reducing risk. It doesn't splash about as much as a gel either.

The gel foams up, but limiting the amount of 'Oxy' can control this foaming - the photos will make more sense of this tomorrow.

My test is now four hours in and I'll take the next photos tomorrow morning, then I should be into the home straight, it will probably take one more treatment to finish the job (or the half I am treating anyway).

[pkillo]

Originally Posted by Merlin

Okay, let's take this one piece at a time.....

Sounds good

The 'Oxy will create gas as the TAED in it reacts with the hydrogen peroxide; it is a catalyst and breaks down the peroxide. There are also perborates and percarbonates present which are also catalysed into producing peroxides.

I have a fairly basic knowledge of chemistry (2 semesters at university level) and I can't find my chem textbook right now, so forgive me if I don't pick up on this as rapidly as possible.

Don't worry, the gas output is very slow and not likely to produce a hazard in the quantities used. You won't blow the house up or anything like that. I am a former industrial chemist and currently a Safety Manager, I would not release an inherently unsafe process onto the masses, the liability would be mind-boggling if I did, so rest easy on that score; the normal precautions in handing chemicals apply - gloves and eye protection.

Hah. I don't think I'll blow myself up, or one of you guys who has tried it would have already done so. I'm more concerned about byproducts that might be hazardous. But I'm guessing you've done the equations and know what's what here. OTOH, I doubt I can buy exactly the same brand of detergent you're getting, and I don't think they have to put the exact ingredients list on the box like with food products, do they? So I don't know how to figure out what to go out and buy, exactly.

We are only intrested in a small area of the UV spectrum around 620-650 wave numbers or thereabouts, because that's the wavelength that causes the bromine bonds to vibrate and break. I've used a standard filament UV bulb and an energy saving version and I can't tell the difference in how they affect the process, apart from the fact that the energy saving version produces less visible light. My guess is the energy saving compact fluorescent bulb is better than the filament type.

Hmm.. I really wish I had paid more attention to the physical sciences. gack. I'm trying to convert wavenumbers to wavelength in meters and getting completely wrong answers. You're talking cm^-1, not inverse meters, right?

Bah.. two sheets of paper later, I give up. I'm trying to compare against wavelengths in nanometres which seems to be what manufacturers like to put on their websites. Anyway, if you could help me with the conversion factors I'd like to track down a high intensity lamp that will have an output band in the range you've given and see if the process can't be sped up. I have no place in my small apartment to leave a blacklight bulb on for three days, but if I could put one on a timer for a couple of hours and be done, that'd be awesome.

The whole point of making this into a gel version is that you use a lot less of the chemicals to get the same effect; you don't need a tankful of liquid when half a pint of gel painted on a surface will do. Less chemicals = more safety in my book, it's about reducing risk. It doesn't splash about as much sa a gel either.

It's really cool that you've taken it this far.

[Merlin]

The results......

I've posted the results of how the gel foams up, it is quite controllable. The pictures taken after two, four and six hours show how the yellowing is gradually removed. The case could probably do with another dose but this is enough to show that even severe discolouring can be reversed in quite a short space of time.

Impressive, huh?

[tonyyeb]

My god! That is the best example of how well this process can work be far!

Cracking stuff Merlin!

[Zetr0]

@Merlicious



now thats Laying It Down m8y, great! stuff indeed.

in fact words and smilies fail me... I am in Awe!

[Zetr0]

@Moderators

this thread needs sticking NOW!!!!!

[tonyyeb]

Originally Posted by Zetr0

@Moderators

this thread needs sticking NOW!!!!!

Amen!

And the guide thread should maybe be merged with it?

[twizzle]

i like zetro`s " Retro-Brite "

although you might not be able to patent the formula ?
you could certainly patent the brand name Retro-Brite

[Zetr0]

Originally Posted by twizzle

i like zetro`s " Retro-Brite "

although you might not be able to patent the formula ?
you could certainly patent the brand name Retro-Brite

as much as I love the Kudo's my friend it was merlicious that came up with "Retr0-brite"

i just added a zero '0' instead of an 'o'

@Merlicious

you can submit this on OHIM have a read up as this can give you a community trade mark for the product m8.

if you need help let me know and I will see what I can do