Removing yellowing from Amigas with peroxide - Page 17

Merlin · 28 January 2009, 13:11

Tezza over at Vintage Computer Forums has already sorted a VIC-20, see below.

I'd say the machine you have is a similar colour to start with. This was treated with the gel version of our magic brew.

Dimlow · 28 January 2009, 15:18

Quote:

Originally Posted by Merlin

Tezza over at Vintage Computer Forums has already sorted a VIC-20, see below.

I'd say the machine you have is a similar colour to start with. This was treated with the gel version of our magic brew.

WOW!

Dimlow · 28 January 2009, 19:45

Ok seeing as that vic is soooo yellow and mucky, i bought some peroxide only 12% and powered bleach and i will give it a go. As you the UV light will my UV box i use for my PCB's be ok ?

Merlin · 28 January 2009, 19:46

Wow Indeed.

Here's a link to Tezza's blog, where he talks about how he took up the Retr0brite challenge...there are some good pictures of other items he has treated on there as well.

http://www.classic-computers.org.nz/blog

Edit: Powdered bleach? NOOOOO!!! surely you mean an "Oxy" type laundry booster powder, like Vanish Oxy Action?

Chlorine bleach will eventually make the plastic brittle.

12% peroxide is strong enough. That, along with some Vanish Oxy Action and a UV lamp and you will get the job done. You should get enough UV from the light box.

Dimlow · 28 January 2009, 19:47

Read it already, that thread Over at the vintage computers forum got me started on this

Merlin · 28 January 2009, 19:53

Cool; VCF was another site where loads of experiments were done in support of the project by Lorne and Tezza. I am really glad the community took this idea up, even though it sounded wacky at first.

twizzle · 28 January 2009, 20:39

@merlin

did you get any further with registering the trade name?

Merlin · 28 January 2009, 22:44

Nope; it appears that Retro Brite it registered out there already and just changing the o to a zero wouldn't constitute enough of a change to enable us to use it. It's just stuck as a nickname for it and I don't want to change it now.

Besides, I've made the process public domain, which is as it should be; don't you agree?

rkauer · 29 January 2009, 04:57

What about "Retro White" or "Retro Cleaning"?

Sounds good to me, at least.

29 January 2009, 08:55

Hey Merlin. Great work you have done here.. Ive read the entire thread and Im really impressed.

Several people have raised concerns about degredation of the plastic from this process. Specifically, changing the surface of the plastic, making it more rough, or brittle..

Also, there is some concern as to different plastic formulations and adverse reactions that may be more prominant in one type of plastic than another..

Could you please comment on these issues?

Merlin · 29 January 2009, 09:16

Certainly.

The main issue surrounds the use of Chlorine based bleaches to remove the yellowing. While there is little doubt that it works, you need to be aware that Chlorine is about half the size of Bromine in molecular terms (see page six of this thread). The result is that the Chlorine replaces the Bromine as it is more active, but at the expense of weakening the plastic structure by literally introducing holes into the plastic matrix. Chlorine can also latch onto oxygen from the air, so you haven't really gained anything as the plastic will still oxidise, but will yellow less than before.

The process that has been developed here does not use Chlorine; it just removes the oxygen from the bromine and replaces it with a hydrogen atom. Now, while this may sound like the same scenario as above, we are actually returning the plastic back to it's original state as manufactured and the bromine remains in place, so all is well regarding embrittlement. If you coat the piece after treatment with a clear lacquer, the yellowing won't return as you have sealed the surface so it can't react with oxygen.

Generally, Acetal Butadiene Styrene (ABS) is pretty generic and so far we have seen little difference between computer brands, e.g. Commodore, Atari, Osborne, Televideo, etc. The master batches of the plastic are made by large players in the industry and the only areas that tend to change are the pigments used to provide colour.

Flame retardants used to include chemicals like Antimony Tribromide (Bromine again) but this has fallen out of use due to heavy metal restrictions, particularly in toys (e.g. EN71 Parts 3 and 9). Poly Brominated Diphenyl Ethers (PDBEs) are the most widely used in plastics that need fire retardant properties, for example clear plastic diffusers on lighting, electrical enclosures, furniture etc.

Merlin · 29 January 2009, 23:53

I know I am post wh0ring now, but if anyone is interested in the concepts and theories behind the science on how this works, Google and Wiki are your friends if you look up the following subjects:-

Bromine free radicals, spd hybridisation, protonation, Lewis acids and bases and Bronsted-Lowry acids and bases.

There's some light reading for you...

I was invited by Metalguy66 to sign up at Atari Age, as if we haven't had enough trolling about this at various places already. Here's what I posted - it contains even more explanation about the process.

----------------------------------------------------------------------------------------------------------
Hi guys,

Metalguy66 suggested I pop over here to get trolled by you all.......

Greetings from English Amiga Board, Vintage Computer Forums and Amibay.... all retro sites together...

I am the alchemist who has been writing all of these articles about de-yellowing plastic. This is my first post on here and it's bound to be controversial....

OK, let's lay this out once and for all as simply as I can. Whilst I am aware that acetal butadiene styrene (ABS) can oxidise under light to form the hydroperoxide as others have alluded to on here, here is one thing that you may not be aware of from the threads, as I am still trying to write this process up for a Wiki, but people keep asking me damn fool questions about it

The process ONLY works in the presence of UV light or sunlight; now, that may not seem like a big thing, but the only molecules in the finished plastic that react so quickly to UV light are Bromine molecules from the Poly Brominated Diphenyl Ethers (PDBEs) in the flame retardant. If you try the experiment in the dark with the same chemicals, the parts don't change colour and just get wet. If this wasn't down to Bromine chemistry in the flame retardant, the polymer would react in any conditions, even in the dark; clearly it doesn't.

The only scientific explanation that fits what we are seeing here is the reaction of Bromine under UV light conditions. Bromine has a single electron spare in it's outer p-shell (Does anyone remember electron shells?). Bromine is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5, hence the negative charge of a Bromine radical as it would prefer an even number of electrons. By neutralising it with a single hydrogen created by the catalysis of hydrogen peroxide by tetra acetyl ethylene diamine (TAED) we allow the Bromine to be reduced by the electron and it goes to a stable 4p4 in the outer p-shell.

The key is to use the optimum strength of hydrogen peroxide, which is around 10 to 15%. The white "bloom" you may see is down to peracetic acid which is one of the breakdown products of TAED and this is also a powerful bleach in it's own right. Too strong a solution and it does seem to etch the surface, which is probably the peracetic acid attacking the hydroperoxide of the oxidised polymer as well as working on the bromine molecules.

Now, anyone can feel free to troll this explanation, but after having put months of work and research into this, at least back your argument up with some sort of scientific critique. I am a chemist with 25 year's experience and although I may not have a BSc, I could certainly write a thesis on this subject.

Over to you all for comment.
----------------------------------------------------------------------------------------------------------

I must be a masochist.........

Supamax · 30 January 2009, 01:27

Hi Merlin

,
great thread!

I would suppose that UV is not the only responsible for plastic yellowing, because in a website (http://www.vintagecomputing.com/index.php/archives/189) I saw a SuperNintendo which had the upper part of its case (and only the upper part) yellowed, both outside *and* inside, in a uniform way.
Since the light can't uniformly enter inside the SuperNintendo (there are cables in the way, and electronic components etc.), the cause will probably be heat or some other, but not UV... am I right?

Merlin · 30 January 2009, 06:08

@Supamax

The effect you saw on that site could be simply down to different masterbatches of the ABS plastic; a difference in the levels of flame retardants between two batches could give this effect. It could also be oxidation of the polymer. Until you get that case under UV with our mixture on it you wouldn't know.

The plastic we are talking about here is really an "alloy" in that it's a matrix of three different polymers - acetal, butadiene and styrene. Image for a moment that these are A, B and C. The combinations that you could get by making a matrix of these are as varied as DNA, so even though it's called ABS, the actual material isn't consistent, it's a generic material.

If you read the post (it's actually a blog) I posted lower down on that page as to what we had discovered and linked to here - small world, isn't it?

Merlin · 30 January 2009, 18:56

@ All

Get this!! Our Retr0brite process has been validated by another very experienced chemist (harpo) over at Atari Age!!

This is what he wrote:
--------------------------------------------------------------------------
OK,
I will chime in here. Professionally, I have BS and MS degrees in chemistry and worked with polymers (plastics and such) for many years. I have not tried this protocol on my own cases that are yellowed yet, because I am just getting back into my old system while teaching my son some computer programming skills (what a great system for teaching programming ).
IMHO, the chemistry that is presented is valid for the mechanism of the "ageing/yellowing" phenomenon and how to reverse it.
When using the materials described be aware that if you don't follow the protocol TO THE LETTER you are out on your own and working with some potent chemical materials and can not be certain of the results you will obtain. I will reiterate what others have said, concentrated hydrogen peroxide is an EXTREMELY powerful oxidizing agent and can cause burns to the skin (I know from first hand experience), explosions when mixed with reducing agents (think rocket fuel), or damage to other materials it comes in contact with.
The 2% hydrogen peroxide you get at the pharmacy is not concentrated enough to accomplish this reaction. You need to use concentrations in the 12-15% range. You can start with the peroxide available at a beauty supply for bleaching hair but be careful to dilute it properly. If you do not know how to calculate the dilution ask for help! And "if a little is good, more must be better" DOES NOT apply here. The purpose of the TAED from the Oxy is to act as a catalyst. A catalyst is an agent in a chemical reaction that reduces the energy required to get the reaction going. You want the catalyst to be "pushing" the reaction, not excess concentration of the peroxide. That is the beauty of the protocol developed. If you use the concentrations and the materials described you should get undetectable amounts of oxidation of the base polymer and only reaction with the bromine compounds. The other thing to remember is that the UV is VERY important. The UV breaks the weak bonds in the peroxide causing the formation of the active radicals. If you have an old "Black Light" pull it out and use it. Otherwise wait until you have a nice sunny day. And as soon as the yellowing is observed to be gone, remove the piece and rinse it thoroughly to get rid of all traces of the TAED and OXY.
My feeling is that those individuals who have observed degradation and roughening of the surface of their plastic cases probably used too high a concentration of peroxide. If you stay on the dilute side and use the catalyst and UV so that only reaction with the bromine is favored, you should get an outstanding result.
As far as slowing the recurrence of the yellowing, I would suggest using a very light coating of ArmorAll or other surface protectant. It will slow the absorption of oxygen onto the surface and also reduce the amount of UV penetration slightly. It will have that slippery overly shiny feel and appearance that all surface protectants leave, but it will work to slow the recurrence of this phenomenon if that is foremost to you.
--------------------------------------------------------------------------

That's all I need to prove that we have got it absolutely right in the way we are going about it. I am absolutely made up, as I was looking for someone impartial to validate my chemistry reasoning all along.

Result!!!! A massive well done to everyone who contributed to this project!!

Merlin · 30 January 2009, 23:46

@ Any German EAB member

So that we credit the right people for the initial discovery passed on by Kristian95, can a member of EAB who is also a member of a1k.org just check on who discovered this in Germany please?

I originally thought it was Luzypher and AMike, but having spent an evening trawling a1k.org reading posts in German, it appears that I could be wrong. It looks like it could have originated from the CBM Museum at Wuppertal and then was taken up by AmigaGTI at a1k.org. I need confirmation on this please.

Zetr0 and I are writing the whole project up and we want to make sure that the right people get the credit they deserve.

Thanks

TCD · 30 January 2009, 23:50

Hi Merlin,

can you give me a link to a thread on a1k.org were this was discussed? I would like to check it for you

Merlin · 30 January 2009, 23:58

No problem, here it is.....

http://www.a1k.org/forum/showthread.php?t=9661

Thanks

Retro-Nerd · 31 January 2009, 00:06

I've read about the H2O2 bleaching in the Forum64 first.

http://www.forum64.de/wbb3/index.php...threadID=18548

TCD · 31 January 2009, 00:09

You're welcome

On the thread in forum64 the OP 'CBM Museum Wuppertal' have tried this method first, although he mentions another thread which discussed this (guess only theoretical given the statement in the first post

). So I would say he's the first one who tried it and posted his results in public

Edit : Okay seems like Retro found the thread

So znarf is the first one who applied the method succcesfully

29 January 2009, 09:16	#331
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	Certainly. The main issue surrounds the use of Chlorine based bleaches to remove the yellowing. While there is little doubt that it works, you need to be aware that Chlorine is about half the size of Bromine in molecular terms (see page six of this thread). The result is that the Chlorine replaces the Bromine as it is more active, but at the expense of weakening the plastic structure by literally introducing holes into the plastic matrix. Chlorine can also latch onto oxygen from the air, so you haven't really gained anything as the plastic will still oxidise, but will yellow less than before. The process that has been developed here does not use Chlorine; it just removes the oxygen from the bromine and replaces it with a hydrogen atom. Now, while this may sound like the same scenario as above, we are actually returning the plastic back to it's original state as manufactured and the bromine remains in place, so all is well regarding embrittlement. If you coat the piece after treatment with a clear lacquer, the yellowing won't return as you have sealed the surface so it can't react with oxygen. Generally, Acetal Butadiene Styrene (ABS) is pretty generic and so far we have seen little difference between computer brands, e.g. Commodore, Atari, Osborne, Televideo, etc. The master batches of the plastic are made by large players in the industry and the only areas that tend to change are the pigments used to provide colour. Flame retardants used to include chemicals like Antimony Tribromide (Bromine again) but this has fallen out of use due to heavy metal restrictions, particularly in toys (e.g. EN71 Parts 3 and 9). Poly Brominated Diphenyl Ethers (PDBEs) are the most widely used in plastics that need fire retardant properties, for example clear plastic diffusers on lighting, electrical enclosures, furniture etc. Last edited by Merlin; 29 January 2009 at 09:55.

30 January 2009, 01:27	#333
Supamax Da Digger :) Join Date: Nov 2008 Location: Monza, Italy Posts: 2,822	Hi Merlin , great thread! I would suppose that UV is not the only responsible for plastic yellowing, because in a website (http://www.vintagecomputing.com/index.php/archives/189) I saw a SuperNintendo which had the upper part of its case (and only the upper part) yellowed, both outside and inside, in a uniform way. Since the light can't uniformly enter inside the SuperNintendo (there are cables in the way, and electronic components etc.), the cause will probably be heat or some other, but not UV... am I right? Last edited by Supamax; 30 January 2009 at 01:40.

30 January 2009, 23:46	#336
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	@ Any German EAB member So that we credit the right people for the initial discovery passed on by Kristian95, can a member of EAB who is also a member of a1k.org just check on who discovered this in Germany please? I originally thought it was Luzypher and AMike, but having spent an evening trawling a1k.org reading posts in German, it appears that I could be wrong. It looks like it could have originated from the CBM Museum at Wuppertal and then was taken up by AmigaGTI at a1k.org. I need confirmation on this please. Zetr0 and I are writing the whole project up and we want to make sure that the right people get the credit they deserve. Thanks Last edited by Merlin; 30 January 2009 at 23:53.

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28 January 2009, 13:11	#321
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	Tezza over at Vintage Computer Forums has already sorted a VIC-20, see below. I'd say the machine you have is a similar colour to start with. This was treated with the gel version of our magic brew.

28 January 2009, 19:45	#323
Dimlow Likes to be thought of as Join Date: May 2008 Location: Kent,UK Age: 55 Posts: 529	Ok seeing as that vic is soooo yellow and mucky, i bought some peroxide only 12% and powered bleach and i will give it a go. As you the UV light will my UV box i use for my PCB's be ok ?

28 January 2009, 19:46	#324
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	Wow Indeed. Here's a link to Tezza's blog, where he talks about how he took up the Retr0brite challenge...there are some good pictures of other items he has treated on there as well. http://www.classic-computers.org.nz/blog Edit: Powdered bleach? NOOOOO!!! surely you mean an "Oxy" type laundry booster powder, like Vanish Oxy Action? Chlorine bleach will eventually make the plastic brittle. 12% peroxide is strong enough. That, along with some Vanish Oxy Action and a UV lamp and you will get the job done. You should get enough UV from the light box.

28 January 2009, 19:47	#325
Dimlow Likes to be thought of as Join Date: May 2008 Location: Kent,UK Age: 55 Posts: 529	Read it already, that thread Over at the vintage computers forum got me started on this

28 January 2009, 19:53	#326
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	Cool; VCF was another site where loads of experiments were done in support of the project by Lorne and Tezza. I am really glad the community took this idea up, even though it sounded wacky at first.

28 January 2009, 20:39	#327
twizzle Registered User Join Date: Sep 2005 Location: taunton.som.uk Age: 73 Posts: 681	@merlin did you get any further with registering the trade name?

28 January 2009, 22:44	#328
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	Nope; it appears that Retro Brite it registered out there already and just changing the o to a zero wouldn't constitute enough of a change to enable us to use it. It's just stuck as a nickname for it and I don't want to change it now. Besides, I've made the process public domain, which is as it should be; don't you agree?

29 January 2009, 04:57	#329
rkauer I hate potatos and shirts Join Date: Oct 2007 Location: Sao Leopoldo / Brazil Age: 58 Posts: 3,482	What about "Retro White" or "Retro Cleaning"? Sounds good to me, at least.

29 January 2009, 08:55	#330
Metalguy66 Posts: n/a	Hey Merlin. Great work you have done here.. Ive read the entire thread and Im really impressed. Several people have raised concerns about degredation of the plastic from this process. Specifically, changing the surface of the plastic, making it more rough, or brittle.. Also, there is some concern as to different plastic formulations and adverse reactions that may be more prominant in one type of plastic than another.. Could you please comment on these issues?

29 January 2009, 23:53	#332
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	I know I am post wh0ring now, but if anyone is interested in the concepts and theories behind the science on how this works, Google and Wiki are your friends if you look up the following subjects:- Bromine free radicals, spd hybridisation, protonation, Lewis acids and bases and Bronsted-Lowry acids and bases. There's some light reading for you... I was invited by Metalguy66 to sign up at Atari Age, as if we haven't had enough trolling about this at various places already. Here's what I posted - it contains even more explanation about the process. ---------------------------------------------------------------------------------------------------------- Hi guys, Metalguy66 suggested I pop over here to get trolled by you all....... Greetings from English Amiga Board, Vintage Computer Forums and Amibay.... all retro sites together... I am the alchemist who has been writing all of these articles about de-yellowing plastic. This is my first post on here and it's bound to be controversial.... OK, let's lay this out once and for all as simply as I can. Whilst I am aware that acetal butadiene styrene (ABS) can oxidise under light to form the hydroperoxide as others have alluded to on here, here is one thing that you may not be aware of from the threads, as I am still trying to write this process up for a Wiki, but people keep asking me damn fool questions about it The process ONLY works in the presence of UV light or sunlight; now, that may not seem like a big thing, but the only molecules in the finished plastic that react so quickly to UV light are Bromine molecules from the Poly Brominated Diphenyl Ethers (PDBEs) in the flame retardant. If you try the experiment in the dark with the same chemicals, the parts don't change colour and just get wet. If this wasn't down to Bromine chemistry in the flame retardant, the polymer would react in any conditions, even in the dark; clearly it doesn't. The only scientific explanation that fits what we are seeing here is the reaction of Bromine under UV light conditions. Bromine has a single electron spare in it's outer p-shell (Does anyone remember electron shells?). Bromine is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5, hence the negative charge of a Bromine radical as it would prefer an even number of electrons. By neutralising it with a single hydrogen created by the catalysis of hydrogen peroxide by tetra acetyl ethylene diamine (TAED) we allow the Bromine to be reduced by the electron and it goes to a stable 4p4 in the outer p-shell. The key is to use the optimum strength of hydrogen peroxide, which is around 10 to 15%. The white "bloom" you may see is down to peracetic acid which is one of the breakdown products of TAED and this is also a powerful bleach in it's own right. Too strong a solution and it does seem to etch the surface, which is probably the peracetic acid attacking the hydroperoxide of the oxidised polymer as well as working on the bromine molecules. Now, anyone can feel free to troll this explanation, but after having put months of work and research into this, at least back your argument up with some sort of scientific critique. I am a chemist with 25 year's experience and although I may not have a BSc, I could certainly write a thesis on this subject. Over to you all for comment. ---------------------------------------------------------------------------------------------------------- I must be a masochist.........

30 January 2009, 06:08	#334
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	@Supamax The effect you saw on that site could be simply down to different masterbatches of the ABS plastic; a difference in the levels of flame retardants between two batches could give this effect. It could also be oxidation of the polymer. Until you get that case under UV with our mixture on it you wouldn't know. The plastic we are talking about here is really an "alloy" in that it's a matrix of three different polymers - acetal, butadiene and styrene. Image for a moment that these are A, B and C. The combinations that you could get by making a matrix of these are as varied as DNA, so even though it's called ABS, the actual material isn't consistent, it's a generic material. If you read the post (it's actually a blog) I posted lower down on that page as to what we had discovered and linked to here - small world, isn't it?

30 January 2009, 18:56	#335
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	@ All Get this!! Our Retr0brite process has been validated by another very experienced chemist (harpo) over at Atari Age!! This is what he wrote: -------------------------------------------------------------------------- OK, I will chime in here. Professionally, I have BS and MS degrees in chemistry and worked with polymers (plastics and such) for many years. I have not tried this protocol on my own cases that are yellowed yet, because I am just getting back into my old system while teaching my son some computer programming skills (what a great system for teaching programming ). IMHO, the chemistry that is presented is valid for the mechanism of the "ageing/yellowing" phenomenon and how to reverse it. When using the materials described be aware that if you don't follow the protocol TO THE LETTER you are out on your own and working with some potent chemical materials and can not be certain of the results you will obtain. I will reiterate what others have said, concentrated hydrogen peroxide is an EXTREMELY powerful oxidizing agent and can cause burns to the skin (I know from first hand experience), explosions when mixed with reducing agents (think rocket fuel), or damage to other materials it comes in contact with. The 2% hydrogen peroxide you get at the pharmacy is not concentrated enough to accomplish this reaction. You need to use concentrations in the 12-15% range. You can start with the peroxide available at a beauty supply for bleaching hair but be careful to dilute it properly. If you do not know how to calculate the dilution ask for help! And "if a little is good, more must be better" DOES NOT apply here. The purpose of the TAED from the Oxy is to act as a catalyst. A catalyst is an agent in a chemical reaction that reduces the energy required to get the reaction going. You want the catalyst to be "pushing" the reaction, not excess concentration of the peroxide. That is the beauty of the protocol developed. If you use the concentrations and the materials described you should get undetectable amounts of oxidation of the base polymer and only reaction with the bromine compounds. The other thing to remember is that the UV is VERY important. The UV breaks the weak bonds in the peroxide causing the formation of the active radicals. If you have an old "Black Light" pull it out and use it. Otherwise wait until you have a nice sunny day. And as soon as the yellowing is observed to be gone, remove the piece and rinse it thoroughly to get rid of all traces of the TAED and OXY. My feeling is that those individuals who have observed degradation and roughening of the surface of their plastic cases probably used too high a concentration of peroxide. If you stay on the dilute side and use the catalyst and UV so that only reaction with the bromine is favored, you should get an outstanding result. As far as slowing the recurrence of the yellowing, I would suggest using a very light coating of ArmorAll or other surface protectant. It will slow the absorption of oxygen onto the surface and also reduce the amount of UV penetration slightly. It will have that slippery overly shiny feel and appearance that all surface protectants leave, but it will work to slow the recurrence of this phenomenon if that is foremost to you. -------------------------------------------------------------------------- That's all I need to prove that we have got it absolutely right in the way we are going about it. I am absolutely made up, as I was looking for someone impartial to validate my chemistry reasoning all along. Result!!!! A massive well done to everyone who contributed to this project!!

30 January 2009, 23:50	#337
TCD HOL/FTP busy bee Join Date: Sep 2006 Location: Germany Age: 46 Posts: 31,980	Hi Merlin, can you give me a link to a thread on a1k.org were this was discussed? I would like to check it for you

30 January 2009, 23:58	#338
Merlin AmiBay MegaMod Join Date: Mar 2007 Location: Manchester, UK Age: 62 Posts: 1,163	No problem, here it is..... http://www.a1k.org/forum/showthread.php?t=9661 Thanks

31 January 2009, 00:06	#339
Retro-Nerd Missile Command Champion Join Date: Aug 2005 Location: Germany Age: 52 Posts: 12,457	I've read about the H2O2 bleaching in the Forum64 first. http://www.forum64.de/wbb3/index.php...threadID=18548

31 January 2009, 00:09	#340
TCD HOL/FTP busy bee Join Date: Sep 2006 Location: Germany Age: 46 Posts: 31,980	You're welcome On the thread in forum64 the OP 'CBM Museum Wuppertal' have tried this method first, although he mentions another thread which discussed this (guess only theoretical given the statement in the first post ). So I would say he's the first one who tried it and posted his results in public Edit : Okay seems like Retro found the thread So znarf is the first one who applied the method succcesfully

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