Destroying a CD - microwave it?

"Clark W. Griswold, Jr." wrote:
I've never quite understood this - you mean the side with the label?
Isn't the recording done on the bottom (blank) side?

No - that's just a clear plastic disk. For CDROMs, the dye is immediately under
the top label.
DVDs sandwich the dye layer between two plastic discs, so they are a bit more
resistant to damage.

I'm sooo confused.

Since the recording takes place between the two layers, what purpose
do the bottom grooves serve?

On Mon, 03 Jan 2005 20:42:44 GMT, Dave Balcom
wrote:

On Mon, 03 Jan 2005 08:08:05 -0800, Steve wrote:

}According to an article in CNET, "The best way to destroy CD-Rs is to
}microwave them on high for five seconds."

I thought microwaves work on the moisture content of the food you are
cooking? Maybe the dye is liquid enough to create heat...

A good pair of heavy scissors works. I cut my old discs into pieces...

Later,
Dave

Microwaves sort of do, but water isn't the only material that
microwaves affect.

A microwaves can cause microcurrents in metal objects. It's why
you're told not to put metal objects in the oven. If the metal object
touches a conductive surface inside the oven, the current generated
may be enough to fry the magnetron. Otherwise, these microcurrents
just heat up the metal object a whole lot. I'm not suggesting you try
it, but a spoon in a coffee cup heats up a whole lot.

In the case of the CD, the layer is a thin foil layer and it gets hot
enough to vapourize parts of it. It then arcs over these broken paths
along the vapourized metal "clouds" to give you the light show.

You probably won't damage the microwave in any big way by doing it,
but if you nuke it too long, the disc may burst into flame or leave a
scorch mark. It's probably a small risk though.
---------------------------------------------

MCheu

Steve wrote:

I'm sooo confused.

Since the recording takes place between the two layers, what purpose
do the bottom grooves serve?

What grooves are you talking about? DVD and CDR blanks are smooth on the bottom
external surface. On the top as well, for that matter.

"Clark W. Griswold, Jr." wrote:
Since the recording takes place between the two layers, what purpose
do the bottom grooves serve?

What grooves are you talking about? DVD and CDR blanks are smooth on the bottom
external surface. On the top as well, for that matter.

Oops, you're right, I'd been seeing grooves when there weren't any
there. This is what happens when you get old. Sigh.

"Steve" wrote in misc.consumers:
Ok, thanks. I've been mostly snapping them in half if I wanna destroy
them...

This is my technique too, though I was surprised at how sturdy they
are.

--
Stan Brown, Oak Road Systems, Tompkins County, New York, USA
http://OakRoadSystems.com/
"Don't move, or I'll fill you full of [... pause ...] little
yellow bolts of light." -- Farscape, first episode

Steve wrote:
"Clark W. Griswold, Jr." wrote:
Since the recording takes place between the two layers, what purpose
do the bottom grooves serve?

What grooves are you talking about? DVD and CDR blanks are smooth on
the bottom external surface. On the top as well, for that matter.

Oops, you're right, I'd been seeing grooves when there weren't any
there. This is what happens when you get old. Sigh.

Are you sure you weren't trying to play those old 45s

Steve wrote:

Oops, you're right, I'd been seeing grooves when there weren't any
there. This is what happens when you get old. Sigh.


Actually, Verbatim sells CDR blanks that do gave grooves in the top. They look
like 45s ("What are 45s, daddy?") - but are purely decorative.

In article ,
Dave Balcom wrote:

On Mon, 03 Jan 2005 08:08:05 -0800, Steve wrote:

}According to an article in CNET, "The best way to destroy CD-Rs is to
}microwave them on high for five seconds."

I thought microwaves work on the moisture content of the food you are
cooking? Maybe the dye is liquid enough to create heat...

A good pair of heavy scissors works. I cut my old discs into pieces...

Later,
Dave

I have a pair of 10" sheet metal snips (Diamalloy DS-10. They look like
a pair of large scissors with short 2 1/2" blades). I keep them in my
desk just for cutting up CD's, credit cards, cardboard and the like.

They aren't expensive, and make cutting up stuff like that a breeze...
actually come in handy quite often, and take up little space.

Erik

Michael Black wrote:

Steve ) writes:
"Dr. Rastis Fafoofnik" wrote:
Deeply scratching the TOP side will render them useless. As long as you see
shiny bits of foil coming up, it's done.

I've never quite understood this - you mean the side with the label?
Isn't the recording done on the bottom (blank) side?

The foil is closer to the surface on the label side. It's easier to
actually damage the foil by going at it from the label side.

Moreover, I read recently that adding those pretty labels that you went
to so much work to make actually damages the CD/DVD.

--
Cheers, Bev
================================================== ==============
I can picture a world without war, without hate. I can picture
us attacking that world, because they'd never expect it.

Steve ) writes:
Andy Hill wrote:
On CD-Rs, the dye layer (the part that gets "recorded") is embedded in the CD,
but is actually much closer to the label side than to the substrate (the
underneath side). If you can score down through the thin protective layer (the
very "top" of the CD) down to the reflective layer (the "foil" Rastis refers
to), you'll do a pretty good job of trashing the CD. Good enough to stop
your typical dumpster diver from grabbing anything off the CD, anywho.

Ok, thanks. I've been mostly snapping them in half if I wanna destroy
them...

And realistically, that is good enough for all but the most paranoid.
Especially if one was to keep the halves separate when tossing them out,
like putting each half out on separate garbage days, or leaving one half
in one public trash can and othe other half in another.

Like anything, the effort someone will make to recover data goes up only
as the value of that data goes up. So if the cdrom is marked as being from
someone well know, there is much more incentive to recover that data. But
they have to way that against the effort.

Someone finding an intact cdrom may try it out for curiosity sake. If it's
broken in half, that lowers the number who will make the effort, considerably.
if they can't find the other half, few will bother, and so on.

Micahel