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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: XDelusion on May 29, 2005, 11:31:07 AM

Title: Removing Yellow Tarnish?
Post by: XDelusion on May 29, 2005, 11:31:07 AM
How do I remove the yellow Tarnish from my old Amiga? Or is it even possible?
Title: Re: Removing Yellow Tarnish?
Post by: odin on May 29, 2005, 11:37:28 AM
Depends, if it's muck from having been around smokers it should be easy to remove with a general purpose cleaner diluted in some water. However if it's yellowness due to having been exposed to UV radiation you can't clean that. Your only option would be to sand the yellow layer off or paint the case.
Title: Re: Removing Yellow Tarnish?
Post by: Doppie1200 on May 29, 2005, 11:42:38 AM
Sorry but it is impossible.

Search the web/forum for 'yellowing amiga' and you'll find this is a common problem.

The plastic is oxydizing due to exposure to sunlight. At least that is the most common explaination. This means its yellow all the way through or at least a good portion of the plastic.

For the case this is not that much of a problem. You could opt for spraypainting it in it's original colour or somethink kinky.

For the keyboard it is a desaster since spraypainting will make you loose all the printing on the keys.



Maybe you are in luck and is the yellowing caused by nicotine (read heave smoking near the machine). This should be cleanable. If else you are out of luck. But should you happen to find a cure please notify us.


Edit: I should learn to type faster and shorter messages. Someone beat me to it  :lol:
Title: Re: Removing Yellow Tarnish?
Post by: XDelusion on May 29, 2005, 11:43:16 AM
Ok, thankx.
Title: Re: Removing Yellow Tarnish?
Post by: Argus on May 29, 2005, 12:18:59 PM
Speaking of UV, my machines are like vampires...by day they live in the dark and only come out at night.  The dreaded yellowing is a real problem and I recommend closing the blinds when you leave for the day to minimize light exposure to the plastic (if you don't want a jaundiced Amiga, that is).
Title: Re: Removing Yellow Tarnish?
Post by: odin on May 29, 2005, 12:28:41 PM
Or, alternatively, you could place your precious Amigas in a vacuum...
Title: Re: Removing Yellow Tarnish?
Post by: starf81 on May 29, 2005, 01:37:06 PM
Hi!

In these days I'm "restoring" an old Amiga 1000 that was very yellowed after many years under the sun light. Now looks like new... I've had success using bleach.
Since I've obtained a very good result, I think to put online a tutorial with my "work".

Meantime, let me know if you need additional infos...

Alex
Title: Re: Removing Yellow Tarnish?
Post by: guest1955 on May 29, 2005, 01:44:34 PM
I remember using bleach (Or some bleach based kitchen cleaner) on my 1200, with little success.
I think the only way to removing the yellowing is to spray it white again. But I'm not sure what you could do with the keys though (Obviously if you just spray the keyboard, you are going to lose all the decals on the keyboard- so you'll end up with one of these (http://hardware.slashdot.org/article.pl?sid=05/05/25/123240&tid=227) for free!)
Title: Re: Removing Yellow Tarnish?
Post by: T_Bone on May 29, 2005, 02:52:59 PM
Quote

odin wrote:
Or, alternatively, you could place your precious Amigas in a vacuum...


That would suck. :-P
Title: Re: Removing Yellow Tarnish?
Post by: blobrana on May 29, 2005, 03:09:11 PM
Hum,
Bathe it in carbon dioxide (placed in a large tub)...

But a cheaper way would be just to ware yellow tinted glasses when you want to play – that way you’ll never notice the yellowing…
Title: Re: Removing Yellow Tarnish?
Post by: guest1955 on May 29, 2005, 03:26:09 PM
Or alternatively, don't ever look down at the keyboard, and keep telling yourself it's still as new.
Title: Re: Removing Yellow Tarnish?
Post by: adolescent on May 29, 2005, 05:00:41 PM
I woudln't say it's impossible as above (although, it's usually easier just to find a newer/better condition case or keyboard).  Check the link below, I don't read the language, but the pictures speak for themselves.

http://www.rabayjr.com/monte_o_seu_hardware.htm
Title: Re: Removing Yellow Tarnish?
Post by: PaSha on May 29, 2005, 05:10:42 PM
Quote

blobrana wrote:
Hum,
Bathe it in carbon dioxide (placed in a large tub)...

But a cheaper way would be just to ware yellow tinted glasses when you want to play – that way you’ll never notice the yellowing…

Carbon dioxide? As is dry ice?

-Paul
Title: Re: Removing Yellow Tarnish?
Post by: PaSha on May 29, 2005, 05:16:04 PM
Quote

adolescent wrote:
I woudln't say it's impossible as above (although, it's usually easier just to find a newer/better condition case or keyboard).  Check the link below, I don't read the language, but the pictures speak for themselves.

http://www.rabayjr.com/monte_o_seu_hardware.htm


Have a look at the bottles on the picture, one is acetone. Acetone literally eats most kinds of plastic (Acetone=nail polish remover), so be very careful, and clean the stuff with normal soap&water afterwards. It also eats brain cells, so either use a mask, or do this outdoors.
Title: Re: Removing Yellow Tarnish?
Post by: boing on May 29, 2005, 10:52:19 PM
>However if it's yellowness due to having been exposed to UV radiation
>you can't clean that. Your only option would be to sand the yellow layer off or paint the case.

It really pisses me off when people who don't know the answer just conclude that because *they* don't have a solution, that it must be impossible.  There are precious few "can do" people in the Amiga world today.

I was going to suggest Didi-7, or Bleach or any of a number of cleaning items that might whiten the afflicted plastic.  Test a small 1" square area on the bottom of your Amiga first though, and wipe it clean, rinse and observe for about a week before proceeding.

>http://www.rabayjr.com/monte_o_seu_hardware.htm

Cool.  English version?




Title: Re: Removing Yellow Tarnish?
Post by: mattabat on May 30, 2005, 02:40:24 AM
Some have recommended some very harsh chemicals..
I recommend using undiluted window cleaner. Very effective. Apply to a cloth and clean *carefully*.
Title: Re: Removing Yellow Tarnish?
Post by: J-Golden on May 30, 2005, 04:05:43 AM
 :-(
Quote

boing wrote:


>http://www.rabayjr.com/monte_o_seu_hardware.htm

Cool.  English version?




Yes, not only theyellowing sollution, but I'd like to beable to read the other info as well...

J-Golden
Title: Re: Removing Yellow Tarnish?
Post by: Doobrey on May 30, 2005, 05:22:49 AM
Then feast your eyes on the wonders of Babelfish (http://babelfish.altavista.com/babelfish/trurl_pagecontent?url=http%3A%2F%2Fwww.rabayjr.com%2Fmonte_o_seu_hardware.htm&lp=pt_en)

OK, it's not a perfect translation, but could anyone tell me what the hell this is supposed to mean?
Quote
Not wall lamp this product on letters printed or logotipos
:lol:
Title: Re: Removing Yellow Tarnish?
Post by: odin on May 30, 2005, 09:47:03 AM
Quote

boing wrote:
>However if it's yellowness due to having been exposed to UV radiation
>you can't clean that. Your only option would be to sand the yellow layer off or paint the case.

It really pisses me off when people who don't know the answer just conclude that because *they* don't have a solution, that it must be impossible.  There are precious few "can do" people in the Amiga world today.

What I meant was, was that UV yellowed plastic has changed chemically and can't be made white, unless you remove the yellow layer of plastic by sanding or (which people have indeed suggested and I indeed failed to say) using chemicals to remove a small layer of plastic.
Title: Re: Removing Yellow Tarnish?
Post by: PaSha on May 30, 2005, 11:19:43 AM
Quote

Doobrey wrote:
Then feast your eyes on the wonders of Babelfish (http://babelfish.altavista.com/babelfish/trurl_pagecontent?url=http%3A%2F%2Fwww.rabayjr.com%2Fmonte_o_seu_hardware.htm&lp=pt_en)

OK, it's not a perfect translation, but could anyone tell me what the hell this is supposed to mean?
Quote
Not wall lamp this product on letters printed or logotipos
:lol:

I'm guessing something in the direction of "do not apply this product to printed letters/logos" (as in don't use this stuff to clean your keyboard, as it will give you a 'das keyboard')
Quote
so you'll end up with one of these (http://hardware.slashdot.org/article.pl?sid=05/05/25/123240&tid=227) for free!)

-Paul
Title: Re: Removing Yellow Tarnish?
Post by: Jeff on May 30, 2005, 05:04:30 PM
I had hopes of the method on the website working but it doesn't look good so far.  I tried polish remover which is diluted acetone on a badly yellowed A4000 drive bay blank and it didn't even touch it.

I really can't see how this person achieved the results in the pictures unless they are all nicotine stains that he is working with.

I have some yellowed Amiga stuff that I would really like restored, like my A3070, A1020, A3000T, A4000, ect. Hard to find.  I have stronger chemicals, however most of them will eat the plastic.

Jeff
Title: Re: Removing Yellow Tarnish?
Post by: Martin_Lee on May 30, 2005, 06:56:23 PM
i doubt strong chemicals is a good idea, but if you want them white again youll have to get that top layer of
plastic off somehow, either sanding or strong chemicals.

i guess you could sand, prime and paint them instead?

theres no other way of doing it.
Title: Re: Removing Yellow Tarnish?
Post by: edgar on May 30, 2005, 09:41:07 PM

Or, maybe you could find a broken miggy (at a car boot sale or  somethin' else) and then just change the cases over.  The "yellowed" case would look much better if it housed a broken circuit board, anyway.

edgar. :-)
Title: Re: Removing Yellow Tarnish?
Post by: XDelusion on May 31, 2005, 12:20:17 AM
Ok, thankx for all the help! Curse the sun. Guess I'm going to do a paint job. I should use Model Paint right?
Title: Re: Removing Yellow Tarnish?
Post by: Martin_Lee on May 31, 2005, 12:29:01 AM
model paint? noooo! use a matt spray paint or car paint methinks
Title: Re: Removing Yellow Tarnish?
Post by: terminator on May 31, 2005, 01:46:42 AM
Quote

XDelusion wrote:
How do I remove the yellow Tarnish from my old Amiga? Or is it even possible?


That's a normal result of the plastic aging.  Best bet is to paint it.  You could try various cleaners, but there is a possiblity of damaging the finish.  If it's safe to use on your hands, it probably won't hurt plastic.  But some hand cleaners do contain solvents... the kind that craze plastics.

There is a place here that recycles computers.  The owner stated that once the plastic yellows, it's garbage.  It can't be recycled.

It doesn't hurt to try.  I've seen A500s that smelled of smoke yet worked.  Seemed it had been in a house fire...  It was cleaned, but the smell remained.

Tobacco is bad. The residues get everywhere.  Not good for electronics.

Title: Re: Removing Yellow Tarnish?
Post by: terminator on May 31, 2005, 01:55:10 AM
Quote

Martin_Lee wrote:
model paint? noooo! use a matt spray paint or car paint methinks


Some of them auto paints are quite wicked when it comes to solvents... But there are so many colours.  The metallics would look whey kewl. Most car parts places can even mix a colour.  Some can even make a spray bomb.

Check with a place that deals in paints, they can help.  Primer wouldn't hurt either.  Might protect the paint from plastic reacting with it.

If painting with a metallic: Everything should be painted in the position it will be used in. Otherwise the effect will not work, and might even look ugly when you reassemble everything.
Title: Re: Removing Yellow Tarnish?
Post by: Martin_Lee on May 31, 2005, 07:43:57 AM
definately need primer!!!!
Title: Re: Removing Yellow Tarnish?
Post by: gazsp on May 31, 2005, 08:46:54 AM
I had some success by removing the outer casing and leaving it in a bath of bleach and warm water for about an hour.

I then used a sponge to clean off any other dirt and rinsed it off with cold water, and shoved it on a towel on a radiator to dry.

Title: Re: Removing Yellow Tarnish?
Post by: fillosauru on May 31, 2005, 01:08:30 PM
Hey, I tried the bleach thing myself, and it barely worked;
I did not get a white A500 case, but it was not so 'yellowed' as before the treatment.
And I left for a day in the bleach+water solution!
Let's say, half bleach and half tap water.
And the whitening was not homogenous, and as a result, I have a A500 case with pathches of white and yellow!  :lol:
Title: Re: Removing Yellow Tarnish?
Post by: sizzlingd on May 31, 2005, 01:39:39 PM
When I first got my A1200,it had some of its keys slightly yellowed,especially letter F,and I too thought about cleaning it up.But you must remember that the Amiga yellowing is just a sign of ageing and I'd rather have a slightly yellowed Amiga that works fine,than an Amiga with a melted keyboard due to using some harsh cleaning substance being used on it.
Nothing stays new forever,so just enjoy the Amiga as it is. :-D