re: Anyone know what type of plastic Commodore computers are manufactured from?

I have looked at the retr0brite website, and gone throgh all the 
information there.

It is my opinion that this procedure has not been adequately tested, and 
there is a possibility that this procedure may cause long term damage to 
the plastic.

I am a chemist and have some experience testing resins.

The retr0brite information mentions a white "bloom" on the plastic from 
over treatment.  This condition is permanent.  It also represents chemical 
damage to the plastic.

A common procedure to determine the chemical resistance of polymers, is to 
put various reactive chemicals on the surface and determine whether, and 
how much time it takes for noticeable chemical damage to occur.  This 
usually shows up as a white "bloom", but this is not the only damage. 
Polymers can also suffer damage that is not visible, but causes the 
polymer to lose its strength and prematurely "age".

The retr0brite information says that you should be careful not to over use 
the chemicals so that the white "bloom" does not occur.  But this does not 
necessarily mean that chemical damage has not occured.  If it takes x 
amount of time to create the white "bloom", then using it for half that 
time probably means that half the damage has occured.  Whether the damage 
is visible is not the real question here.

It would take aging tests to determine whether the plastic is damaged from 
the retr0brite procedure.  I do not see any indication that retr0brite 
treated plastics have been subjected to aging tests.






On Fri, 23 Jul 2010, Bill Degnan wrote:

>
> Search for "retr0brite project"
> Bd
>
>
> -------- Original Message --------
>> From: "Stingray" <thestingray64@gmail.com>
>> Sent: Friday, July 23, 2010 10:37 PM
>> To: cbm-hackers@musoftware.de
>> Subject: Anyone know what type of plastic Commodore computers are
> manufactured  from?
>>
>> Anyone know specifically what plastic the C64 and C64C are manufactured
> from?
>>
>> I have been wondering how to stop plastic Commodore gear from fading.
>> I found a really good link on this (also explains why some of the keys
>> on your C64C are faded and some aren't).
>> http://www.vintagecomputing.co...chives/189
>>
>> Does anyone have any of their own tips on maintaining plastic
>> Commodore equipment?
>>
>> Regards,
>> Stingray
>>
>>        Message was sent through the cbm-hackers mailing list
>
>
>
>       Message was sent through the cbm-hackers mailing list
>

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