jjmac,

Yes, I can only imagine what many of my neighbors think of me, and some of my "tasks", the CD testing being only one of many... ( Sometimes I feel like the guy in the Thomas Dolby video, with his exclaims; Sceince! ) - most of the time, I feel like one of those "testers" for UL (Underwriters Laboratories ), where they try to destroy something, or break it at a point no one would ever attempt.

Case in point, even though a CD-R is not readable, a computer coaster, so to speak, I tend to destroy them so they cant be re-used. Most of the time, I break them, which, as you said, can take a lot of force, and usually tends to send shards of plastic everywhere. I have actually had a CD "blow up" inside a CD-ROM drive; my Significant Other likes to borrow music from the library, and rip the songs off of them. Many times these CDs are the worst, they look like someone has misstreated them for many years, but, not as bad as the test CD I used outside. Well, all I remember was her putting the CD into her ROM drive, starting a abcde, and watching the light flicker a few times. About five minutes of trying to get through the same sector on that CD, the drive all of a sudden, spun up to some high squeel sound, and then a very loud POW!

She, as well as I, looked at the drive, then the konsole, and back to the drive, numerous times, till the command on the konsole finally reported: "No media in drive" and aborted.

Attempts to open the drive failed, even with the paper-clip... So, I downed the system, and completely removed the drive, chassis, and was graced with thousands of pieces of plastic within the inside of the drive. Many of the "chunks" had even embedded themselves into the sides of the drive, my guess is, from the force of centrifical outward speed when the disc had shattered. I delicately removed what I could with my hands, and then used a vacuum to get many of the tiny fragments, put the case back on, and re-installed the drive. To this day, it still appears to be running, and reading, fine... ( but, I dont give much trust to it, since it had eaten a disc. )

So, if anyone thinks that this never happens, and it can only happen on an episode of Myth Busters, dont be too sure of yourself... It does happen, and without having to "over-power" some drive to the point no one would ever do. In the MB episode, I think they were testing the myth that a CD could "blow" and project out the shards to the point of killing someone - I can attest, no one died from our blown disc, everything was contained within the drive, though it did cost us... We had to replace the CD we borrowed from the library

A very nice "side-step" to another topic... Arent we all testers though??? We are running a Distro, made, from the name of the kid in the movie Toy Story, SID, who was the nice child who destroyed his own, and others, toys. So, basically, we are all testers, by choice... Just some of us, tend to go a little farther in our "testing" than others

jjmac, my guess is, as with other things, when trying to "undo" something, requires force, of the opposite it took to "make" it that way... in the case of a metal bar, when trying to "un-bend" it, usually requires more force, more work, and a very delicate nature of getting it back to straight again. My thought on a warped disc is, it is going to require delicate "force" in the opposite direction of the convex, to correct it, and maybe, even, over-force, past the point of center, to get it back to center. Whereas, all of these attempts to correct the disc are all to un-bend it to center, it may require it to be bent past the point of center

Hence, the best results you have gotten is to get it closer to center, and not warped, but not fully... I should also point out, that, if any attempt is made to use "heat" on something, it should be "completely" cooled down before any attempt to remove any weight holding it through the process... i.e. sandwich a CD between glass, heat whole assembly to xxx degrees for xxx minutes, remove heat from assembly, let cool completely, then remove the controlling weight from assembly... I am sure that, removing controlling weight from a "cooling" CD too soon, could render negative results as the CD cools without something to control it from any more warpage...

Oh well... I am amazed, I didnt realize I didnt change my notification e-mail address when I moved, and thought that I just wasnt getting notifications cause there wasnt any, and, here all along, I was just my e-mail problem... Already made many boo-boo's on posting on topics that are more than a few months old... Oh, well...

Good Luck jjmac, if you find a "clear-cut" resolution to this, please inform, I'd be interested in having the knowledge for future,
MS Cuddles
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