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From: wb@freebie.xs4all.nl (Wilko Bulte)
Subject: [TUHS] Recovering flaky CDs
Date: Wed, 31 Oct 2007 19:09:11 +0100	[thread overview]
Message-ID: <20071031180911.GA25151@freebie.xs4all.nl> (raw)
In-Reply-To: <20071031164736.GB22786@freaknet.org>

Quoting asbesto, who wrote on Wed, Oct 31, 2007 at 05:47:36PM +0100 ..
> Wed, Oct 31, 2007 at 08:25:00AM -0800, James Petts wrote:
> 
> > > > > Is there anybody on this list who knows a way of recovering flaky CDs?
> > > > Easiest first step is try using different kinds of CD/CD-R/DVD-R drives.
> > > > I have found some 'unreadable' CDs could be read using a DVD drive.
> > > I remember a very old SONY cd-rom reader capable of reading very
> > > damaged cd! It was the SONY CDU-33A, it has his
> > > own controller, so was not an IDE or SCSI drive. But it can be
> > Those CD Doctor "cleaners" (they actually do a minor
> > resurfacing of the disc) have rescued several discs
> > for me.
> 
> A great problem I had some time ago was a sort of oxydation of the
> cd material; this seem to happen using very bad cd brands. i had

Note that the reflecting layer in factory produced CDs is aluminium.
A thin layer of lacquer is protecting the reflector.

As an interesting eye opening experiment I dumped one of these AOL promo CDs
we used to be bombarded with in a bowl of lukewarm water.  Plain water, 25
degrC. Within a day the aluminium layer had holes in it the size of dimes.
Apparantly the protective lacquer was very substandard.

El-cheapo CDR can have similar characteristics.

Wilko



  reply	other threads:[~2007-10-31 18:09 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-10-31 16:25 James Petts
2007-10-31 16:47 ` asbesto
2007-10-31 18:09   ` Wilko Bulte [this message]
2007-10-31 16:56 ` Warner Losh
2007-10-31 17:15   ` Angus Robinson
2007-11-01  7:59     ` Wesley Parish
2007-11-01  8:03   ` Jochen Kunz
2007-11-01 13:11     ` Pete Turnbull
  -- strict thread matches above, loose matches on Subject: below --
2007-10-31 18:19 James Petts
2007-10-31 18:28 ` asbesto
2007-10-31 19:43   ` Wilko Bulte
2007-10-11 13:14 [TUHS] mach & nextstep Jose R. Valverde
2007-10-30 22:36 ` [TUHS] Recovering flaky CDs (was: mach & nextstep.) Greg 'groggy' Lehey
2007-10-30 23:26   ` [TUHS] Recovering flaky CDs Al Kossow
2007-10-31  9:22     ` asbesto

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