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Old 12 July 2008, 07:19   #61
Kristian95
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in general all chemical processes are sped up by adding heat, even exothermic reactions (heat producing ones), having said that UV might, for this specific reaction, work better, but what we should compare is the energy added to the system (i.e. KJ or calories of UV vs. heat)

EDIT: I am a chemical engineer so I know what I talk about

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Old 12 July 2008, 08:03   #62
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I think that heat and light will accelerate the process cause the dentists use a powerful light to accelerate the process while the bleach is in process

also they make hot the product with heat' water before application
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Old 12 July 2008, 10:12   #63
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Yeah, chemistry basis.

I'm a plastic engineer, myself. But never learnt about removing anti-UV with peroxide.

The anti-UV compound is what makes Amiga cases yellow, not the ABS itself.
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Old 12 July 2008, 15:23   #64
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A bubble tank would really assist this guys,

Grab a small fish tank, attach an air pump with a diffuser on the end of it. around 30-40% peroxide solution and a couple of 30watt UV lamps.... should make a HUGE difference
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Old 12 July 2008, 16:22   #65
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Last night a Loreal hair shampoo advert came on.

If we got the secret peroxide formula and marketed it we could have Dizzy naked with an Amiga on the telly..


Lo-peroxide, because your Amiga's worth it...
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Old 12 July 2008, 17:12   #66
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I'm glad this has proven to work cause I was sus on the background of the first two images in the first post of this thread.
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Old 12 July 2008, 17:29   #67
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Does the bleaching process change the surface of the plastic in any way? ie. does smooth glossy plastic become rough and matte?

edit: Oh and post some more pics... this is the amiga makeover thread after all
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Old 12 July 2008, 17:51   #68
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There are some nice pics on Forum64, i.e this one:

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Old 12 July 2008, 21:29   #69
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Peeps like Kristian95 will know a lot more about this process than me...

...H2O2 is going to work a treat on yellowed plastics (I'd use it myself if I could be bothered to buy some) BUT all plastic ages & any such chemical treatment WILL age it faster...
...this results in more brittle plastic.
No big deal most likely but go easy on how long you stew your Amiga - you only want surface changes or you could end up with stuff snapping off!
AND make sure you use a some kind of neutraliser (lots & lots & lots of water will do) so that the reaction stops when you're happy with the result.
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Old 13 July 2008, 00:32   #70
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Quote:
Originally Posted by Charlie View Post
Peeps like Kristian95 will know a lot more about this process than me...

...H2O2 is going to work a treat on yellowed plastics (I'd use it myself if I could be bothered to buy some) BUT all plastic ages & any such chemical treatment WILL age it faster...
...this results in more brittle plastic.
No big deal most likely but go easy on how long you stew your Amiga - you only want surface changes or you could end up with stuff snapping off!
AND make sure you use a some kind of neutraliser (lots & lots & lots of water will do) so that the reaction stops when you're happy with the result.
I think that sodium bicarbonate+water can be used as neutralizer....it's normally used to neutralize some products that were treated with acid or any other product to oxidize
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Old 13 July 2008, 04:24   #71
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plain water will do as H2O2 is not an acid or base just an oxidizer
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Old 13 July 2008, 04:39   #72
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OK.

Final picture of the process.

Now all other caps are "swimming" in peroxide.

But just to prove something, here is the result on those 3 caps I already tested (can someone notice the difference? ):
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Old 15 July 2008, 05:50   #73
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well I have bleached 2 yellowed keys...and it works !!! I guarantee

the process took aprox 72hs ...but I think more yellowed=more time

after long time we find a real solution for this !!!! yes !!!!!

thanks Kristian95 for bring the info here to EAB!!!

I haven't used light or heat as acceleration of the process....it doesn't need it...only a small flask inside my house away from light or heat........tomorrow I will post some pics

Last edited by laser; 15 July 2008 at 05:57.
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Old 15 July 2008, 08:32   #74
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Super
I'm happy to help rescue Amigas No need to thank me, saving Miggy equipment is all the thanks I could ever want But you could post some hardware Pr0n for Zetro
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Old 15 July 2008, 12:08   #75
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Quote:
Originally Posted by Kristian95 View Post
plain water will do as H2O2 is not an acid or base just an oxidizer
It's slightly acidic... at 20%, it's got a pH of 4.9

It's a strong oxidiser, be careful with it.
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Old 15 July 2008, 15:00   #76
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LOL at 70% H202 is considered a FUEL
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Old 16 July 2008, 00:21   #77
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Excellent! How does the printed stuff, like C= logo and caption on keys fare with this solution?
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Old 16 July 2008, 00:31   #78
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They not fall out, if is that you asking.

Yellowing under the stickers don't go away, too (the stickers impeding this to occur).
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Old 16 July 2008, 00:33   #79
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Cool. Just announced to the wife that I'm off to get some peroxide. She looked at me suspiciously...
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Old 16 July 2008, 00:41   #80
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We use 35% H2O2 at work, for bleaching dyestuffs out of our trade effluent and to buffer the pH after neutralising formaldehyde with caustic soda....

Science Abuse Rules!!
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