Erasing CDs By Using 150,000 Volts of Electricity

ryzvonusef writes "One enterprising individual has created the most secure way to wipe out Compact Discs, by using a step-up transformer and creating a 150,000 Volt pd, whilst a CD rotates in the middle. The sparks arc through the metal in the CD and evaporates it, ripping it all off as the CD rotates. The CD is rendered transparent and unreadable. This may be the most secure method to remove data on conventional recordable CDs used in offices."

Comments

Microwave

[Anonymous Coward]

Does a thorough enough job, almost everyone has one on hand, takes but 2 seconds an

Re:Microwave

[torgis]

+1 for the microwave. While big sparkly arcs of electricity has definite nerd appeal, you can thoroughly destroy a CD with 5 seconds in a microwave.

Re:Microwave

[camperdave]

Because someone with patience can piece a shredded item back together again.

Re:Microwave

[postbigbang]

Which is why four 12 gauge shells ought to be just the masochism that a forensic artist was looking for, after a few CDs are lined up in a row for target practice.

Re:Microwave

[icebike]

Because someone with patience can piece a shredded item back together again.

Not a CD they can't.

Even if you managed to get all the pieces physically back in the correct positions, it would not be readable.
The error rate would overwhelm the redundancy algorithms.

Re:Microwave

[cheater512]

If you only wanted a small portion of the data, it would work just fine.

Even a disc with a lot of errors will still read to a extent.

Re:Microwave

[Whiternoise]

What about something like Ferric Chloride (PCB Etchant), easy to obtain and you could simply sponge it over the disc surface?

Re:Microwave

[Moryath]

Except that:

(a) the worst damage will be closest to the spindle, which is where the data write begins.
(b) properly cross-cut into 1/4" or less width, the shattering rate should eliminate better than 90% of the data between strips.
(c) shattered in such a fashion, oxidization will quickly take care of the remaining data. The leaves will separate, exposing the metal data layer to air, and oxidization will set in damn quick (can you, even with "patience", collect it all AND put it all back together correctly in less than three days?).

Re:Microwave

[cdrguru]

Recordable discs use gold or silver with negligable oxidation of the reflector. You might get some level of degradation of the dye and call that "oxidation" but we're talking about the reflector, right?

Manufactured discs use aluminum which does oxidize somewhat. In extreme environments with lots and lots of humidity you can get the aluminum to oxidize but only a very few people have ever actually seen it. Mostly this is a myth started by the folks proclaming "DVD rot" which has only occurred in some really odd circumstances.

The problem with shredded discs being put back together is that it will take the drive about 1/4th of a turn to regain tracking after a break. You are NOT going to be able to align the spiral across a break - wraps of the spiral on a DVD are around 1000 nanometers apart. They are a whopping 1400 nanometers apart on a CD so that might be as much as 40% easier.

Since visible light has a wavelength around 500 nanometers, we are talking about features that cannot be resolved by magnification. You might, and I say just barely might, be able to do this with an electron microscope and some sort of micro-manipulator. Maybe.

Having a piece of a sector doesn't do you any good really. The data isn't encoded as bytes on the disc and there is physical scrambling of the bytes to spread them out. For example, to read one sector on a CD you have to read three. On a DVD it is worse - you have to read 16 of them.

Re:Microwave

[Moryath]

Recordable discs use gold or silver with negligable oxidation of the reflector. You might get some level of degradation of the dye and call that "oxidation" but we're talking about the reflector, right?

Manufactured discs use aluminum which does oxidize somewhat. In extreme environments with lots and lots of humidity you can get the aluminum to oxidize but only a very few people have ever actually seen it. Mostly this is a myth started by the folks proclaming "DVD rot" which has only occurred in some really odd circumstances.

Actually, I've seen a couple discs with a pinhole flaw in the outer leaf, where oxidation set in (they were stamped, not writable/rewritable). Visually the effect was pretty impressive.

As for the rest... "oxidation" as a substitute for "degradation due to interaction with humidity in open air." I was referring mostly to aluminum stamped discs, but you'll also get plenty of degradation of the inks (they do NOT do well when exposed to high humidity and temperature outside of the sealed casing), plus plain physical damage from rubbing against other objects once the leaves separate.

And you're right about the alignment issues as well. Like I said, once you've knocked the thing into cross-cut pieces at 1/4" width or so, and the leaves have separated on most of the pieces, expecting to retrieve anything from it is ridiculous.

You might as well actually take each piece and scan it with an electron microscope, then try to make a visual image by assembling the piece images, do some form of error correction by algorithm to try to re-create the edge data, create a new master from the full result, re-press a CD from your new master, and then see if you get anything readable.

...Crap. I just gave some asshole with access to an SEM ideas, didn't I?

Re:Microwave

[fuzzyfuzzyfungus]

The bottom(read side) is a layer of polycarbonate, I'm pretty sure it won't even notice Ferric Chloride. The top has a protective lacquer layer over the metal surface, which should also be reasonably resistant(though it is the side far more vulnerable to mechanical damage: The bottom is a good mm of polycarbonate, and can be repaired to a degree with anything of suitably similar transparency and refractive index. Virtually any damage to the top side will destroy at least a portion of the data surface).

The mechanical vulnerability is probably among the easiest angles of attack. Your basic harbor freight belt sander should be able to reduce the data layer to a fine cloud of (probably not recommended for human breathing) fragments in under a second of contact.

Re:Microwave

[JerryLindenburg]

Personally, I've always preferred wood chipppers.

Re:Microwave

[JoeMerchant]

Gotta love anything that involves 150KV spark arcs, but Og the caveman does it better with plain old fire.

Re:Microwave

[Kral_Blbec]

And glue a CD back together? Right...

Re:Microwave

[RobertM1968]

Because someone with patience can piece a shredded item back together again.

No... no they cant. That's a myth based on people doing that with paper. Shred a CD and try it. First, the "foil" section gets stretched and damaged (as it's also peeled away from the plastic disk at the cut edge) - as well as becomes unreadable in the cut areas. Due to the way it's bonded to the plastic, it's largely torn rather than cut (a cross between a tear and a stretch and a cut), making those areas unable to be put back together). In the end, with the size of the data on the disk surface itself, it'd be too damaged (through any industrial card/disk shredder) to be re-assembled.

Regardless, these things melt very nicely - including the data surface. That will leave the entire thing totally unreadable, can be done outdoors (ie: no fumes killing you in your house) and won't run the risk of damaging your microwave.

Re:Microwave

[RobertM1968]

What about something like Ferric Chloride (PCB Etchant), easy to obtain and you could simply sponge it over the disc surface?

Wow, EVERYONE is thinking of the most difficult ways of doing this. (nothing personal - I too like to over-engineer and over think from time to time... not that I'm always the best at the thinking part) ;-)

Simple and cheap and easy methods (choose any one):
- Melt the things
- take a belt sander with fine (or maybe medium) sandpaper to the "label" (ie: non-polycarbonate) side. Let's see someone glue back together the data medium once it's been powderized
- Use a good cross cut shredder (efficiency of doing so covered above) - really, you ain't gettin data after that.

Or get ingenuitive. Nah... I'll save that idea. Maybe patent it...

Re:Microwave

[RobertM1968]

Science geeks have been doing this for years with microwave ovens; though, it was more for the cool light show than for data security.

I am going to hereby retroactively claim all my attempts were for data security (and the light show was just an added bonus).

Now, I just need someone to help me come up with a plausible reason why it was generally AOL CDs I did this too...

Re:Microwave

[tibit]

The reading would be done directly on the SEM image, you don't need to put it in a CD reader or "press" anything. Duh.

Re:Microwave

[Joce640k]

Or... just scratch it up with the point of a pair of scissors. The recording layer of a CD is on the outside and comes off very easily.

Even drawing on it with a ballpoint can wreck it - try it sometime (that's why they invented special "CD pens").

nb. DVDs are different.

Re:Microwave

[geekoid]

no, the can't.

You can NOT rebuild a CD from an industrial grade shredder. This isn't small pieces of paper, it's shattered plastic and dust.

Re:Microwave

[geekoid]

Fists off, you can't reassemble dust, and the shattering will be in a fashion where the probability of reassembly approach 0.

But, hey, shred in a couple of disks together and now it's impossible to reassemble.

Also, go read the Red book before you talk about CDs. Clearly you have no clue on how data is laid out.

Re:Microwave

[geekoid]

don't melt it. It's not needed and it only harms people.

Just freeze it then hit it with a hammer a few time. Hell, do 2 at once.

For those with less sense and less money

[Phibz]

try nuking it in the microwave for 2 - 3 seconds.

Re:For those with less sense and less money

[v1]

actually the foil is VERY quickly shattered, it's quite spectacular and is a good deal safer on the magnetron than the other article today where someone was suggesting microwaving a hard drive

Re:For those with less sense and less money

[Kazymyr]

I've done it dozens of times. My 13-year-old cheapo microwave oven didn't bat a lid. Still going strong.

I think the "easy to damage the microwave" is an urban legend. Someone should submit it to Mythbusters.

Re:For those with less sense and less money

[TheViffer]

This can^H^H^H will destroy a microwave ... not that I know or anything ... it was "my friends" microwave. Besides that nuking them releases a small bit of toxic gas and it is not 100% effective to erase all the data.

Just get a DVD Shredder .. save your microwave, save yourself .. and most importantly you^H^H^H "your friend" will have a microwave to nuke those pizza roles at 11 pm at night.

Re:For those with less sense and less money

[ZosX]

how is anything hard on the magnetron? all it does is emit energy, which the metal readily soaks up and superheats. The real danger is more catching the microwave on fire than anything.

Re:For those with less sense and less money

[MichaelSmith]

Besides that nuking them releases a small bit of toxic gas

Yes I wouldn't want that in the same place as my food.

Re:For those with less sense and less money

[WrongSizeGlass]

It's very easy to damage the microwave when doing so.

Buy a cheap microwave just for this purpose. I'm guessing a 150,000 volt transformer is going to cost you more than $70 (and probably weigh a bit more than a small microwave too).

Re:For those with less sense and less money

[spun]

The thinking goes, the magnetron is basically an antenna, right? So it can pick up as well as transmit energy. If an electric charge builds up and arcs stright into the magnetron, it can blow up. Or something like that. I've never seen it happen, and I've blown up a lot of stuff in microwaves over the years.

A quick google search for "blow up the magnetron" turned up this answer from a microwave engineer:

2. metals in the microwave oven - they will not destroy the oven or cause it to blow up. I routinely heat my coffee with a spoon in the cup. I also did the definitive early research on this in the late 70's and early 80's. But it is possible for metals to arc (spark) under certain conditions. This can be dangerous especially with things like metal twist ties and steel wool. Also, things like the metal trim (silver or gold) around the rims of fine china is dangerous in that the dish or cup can easily beak or shatter - but this due to the trim not being perfectly continuous like a wire that would carry current, Instead the trim has microscopic gaps and that can cause micro-arcs and temperatures exceeding 1000 F locally.

Don't you just love the Internet? We get to be wrong more often, but not for as long.

Re:For those with less sense and less money

[Antidamage]

None of this stops someone from going back in time and getting the original.

The only way to secure your data is by not creating it in the first place. THINK, PEOPLE!

Re:For those with less sense and less money

[mangu]

it's easy to damage the microwave if you keep it running for too long, since the CD doesn't contain a whole lot of water

That's why I put the CD over a half-full glass of water when I do it.

Re:For those with less sense and less money

[v1]

It's not an intuitive thing, don't worry you're not alone in not immediately seeing the problem.

A magnetron is a kind of RF (radio frequency) transmitter. It converts electrical energy into radio energy. This energy leaves the magnetron and bounces around inside the microwave. The frequency used makes it tend to interact with water molecules, and heats them up, changing radio energy into heat energy. And that's what heats the food. (note that foods with significant water content heat best)

The microwave is tuned just like an antenna is tuned, to maximize the use of energy. Energy the magnetron takes from electricity has to go somewhere. Energy sent into the box that isn't absorbed and converted to heat is reflected back to the transmitter. This is aka a "standing wave". The "Standing Wave Ratio" tells how efficient the energy transfer is.

A high SWR means a large percentage of the input energy is being reflected, and back to the transmitter where it must be used and so is converted into heat. Transmitters expect some of this because the conversion isn't perfect to begin with, but they're not designed to handle a LOT of additional energy to dump, and will overheat. Very high frequencies like magnetrons use are especially inefficient to start with, and so they're usually designed to cool heavily, with fans and fins. The heat you feel coming out the back of the microwave is NOT heat from the food, it's the waste heat off the magnetron. Adding too much to that waste heat can overheat and damage the magnetron, sometimes very quickly.

So, if you put a substantial chunk of metal into a tuned cavity like a microwave oven, it will interfere with the transfer of energy and cause a higher SWR, which can damage the magnetron. Running a microwave without anything in it is not recommended for the above reason, but adding metal into the mix makes matters worse. Placing nothing in the cavity besides a substantial piece of metal is about as destructive as you can be. The denser the metal, the bigger the effect.

Re:For those with less sense and less money

[dwillden]

Well this doesn't really "Erase" the data either. The pits are still in the plastic, just apply a new reflective backing and the disk is readable again.

Best is to simply break the disk up either manually or in a shredder.

Re:For those with less sense and less money

[Phibz]

Metal isn't always bad in the microwave and certainly won't blow it up. Many modern microwave food containers have a metal grid in them to diffuse the microwaves as they cook the food.

Although the vaporized foil probably isn't good to breathe or eat.

Re:For those with less sense and less money

[Dogtanian]

Well this doesn't really "Erase" the data either. The pits are still in the plastic, just apply a new reflective backing and the disk is readable again. Best is to simply break the disk up either manually or in a shredder.

Yeah, that's what I thought as well. Still, let's be honest, it was pretty good fun, as you'd expect from the same guy that brought you the self-destructing washing machine. (I recognised his voice on this clip straight away, the accent/style/modus-operandi combo is pretty distinctive once you've seen some of his other videos!)

Re:For those with less sense and less money

[soundguy]

a 9-12 kv neon sign transformer is fairly easy to come by and should be just as effective. It will produce an arc at 1-2 inches and can be drawn out to 5-6 inches. (google "Jacob's Ladder" for video examples) Although I applaud any displays of high voltage for any reason, I'm also a big fan of fire, which takes care of CDs nicely for the price of a match and some flammable fuel.

Re:For those with less sense and less money

[HelioWalton]

are you sure it's not a half empty glass?

Re:For those with less sense and less money

[icebike]

how is anything hard on the magnetron? all it does is emit energy, which the metal readily soaks up and superheats. The real danger is more catching the microwave on fire than anything.

Spoken like one who has never killed a microwave in their day. Its easier than you think. Chances are that its the main circuit board that is actually damaged and not the magnetron itself, but I've killed a couple with no sign of fire. (Lightning in a box, but no smoke and no fire).

Re:For those with less sense and less money

[MacGyver2210]

You are incorrect on several fronts.

It is not damaging to the microwave, unless you happen to be microwaving explosive blasting caps or something. The Magnetron(Microwave Emitter Piece Thingy) is usually so far away from anything in the chamber that it's impossible for enough charge to build up that it can arc back and cause problems. For example, on the microwave model I routinely take apart to use for parts, there is a metal channel to guide the microwaves from an area behind the keypad over to a 'stirrer' which spreads the waves around the food chamber(and often doubles as a cooling fan).

The 'gas' released is actually atomized Aluminum and Aluminum Oxide or Gold(with a negligible amount of combusted lacquer), it is in a quantity so small it is not harmful to anyone, and is no more toxic than most Deodorant/Antipersperant bases or wearing a gold wedding ring.

Re:For those with less sense and less money

[v1]

No, it's not like in the movies, they don't "blow up". They can fry the magnetron or the support electronics, or make a little lightning inside the food compartment. Might smoke a bit, or at best make a nice sparky energetic POP.

And close on the grid but not quite, I was going to mention this in my last post but forgot, newer microwaves all have a vaned fan blade looking affair in them that is in the line of fire in the box. It's often doing double duty as a cooling fan for the food or the magnetron. Its blades are moving, and cause the RF energy to reflect around in a non fixed pattern inside the box (which IS lined with a metal grid), this allows the microwave to heat the food more evenly.

It's like tossing a handball in a handball court, how the ball bounces around depends on where you're standing and what direction you throw. If you throw the same way each time, the ball will travel through the room in the same routes every throw, and there will be places in the room that the ball never gets near. Now imagine I place an exposed fan in the room and you're throwing at the fan every time. Depending on the position of the blade that ball could go almost anywhere. Same thing applies with microwaves. The handball represents the RF energy the magnetron is throwing out.

Re:For those with less sense and less money

[SnarfQuest]

They should try to recover one with a can of siler spray paint. Might be an interesting test.

Re:For those with less sense and less money

[Intrepid imaginaut]

The thinking goes, the magnetron is basically an antenna, right? So it can pick up as well as transmit energy. If an electric charge builds up and arcs stright into the magnetron, it can blow up. Or something like that. I've never seen it happen, and I've blown up a lot of stuff in microwaves over the years.

And this is why I love slashdot.

Re:For those with less sense and less money

[Gavin Scott]

Mod parent up.

It's also not the metal in the oven that's bad for it, it's any configuration where the microwave energy is not absorbed. Metal can absorb (well, couple to, or "receive") microwave energy just fine if it's the right length (this is why the sliced grape plasma thing works too). You can solder a couple short wires onto the end of an incandescent lightbulb, making a little 1/4 wave dipole antenna at 2.45GHz, and the bulb will light up in the oven.

Traditionally the *worst* configuration for damaging the oven is to run it EMPTY (or at least with nothing in it that can absorb the energy). This results in a nearly infinite SWR, with almost all the 600-1200W of energy getting "reflected" back at the transmitter, and it will heat up and die (or melt something important nearby) within maybe 10-30 minutes or so.

Same thing will happen to most transmitters if you disconnect the antenna creating a huge impedance mismatch that literally reflects the energy back to the transmitter. And it's the same reason all high speed communication links (Coax Ethernet, SCSI, etc.) have "terminators" to sink the energy at the end of the transmission line so it doesn't bounce off the end of the cable and echo back down the line.

Metal in the oven is *usually* not a problem the way people think it is. But it will block and reflect (in a more traditional sense) the energy around so that you can't cook a potato wrapped in foil.

Modernist Cuisine has this to say: "Myth: You can't put metal in a Microwave. Fact: Microwaves already have plenty of metal in them: the walls of the oven, the fan [that distributes the microwaves], and so on are all metal! What you need to be careful of is metal that has sharp points or edges. Those features concentrate the electrical field in the oven and cause arcing. Arcing in and of itself isn't too dangerous, but it can ignite dry flammables in the oven. The reason to not use metal cookware is that microwaves cannot penetrate the metal, so your food will not cook."

G.

Re:For those with less sense and less money

[pclminion]

You are incorrect on several fronts. It is not damaging to the microwave

Then explain why it damaged the microwave. Theories are nice, they have to agree with experiment though.

Re:For those with less sense and less money

[cdrguru]

You need to put a cup of water in with the disc. Failure to do this can screw up the magnatron tube and ruin the microwave oven. 3 to 5 seconds is the limit - you can get flames for much longer than that and burning polycarbonate isn't good for anyone.

There is no "toxic gas" other than burning polycarbonate.

Re:For those with less sense and less money

[cdrguru]

Uh, no.

For recordable discs, the data is in the dye. Lose the reflector (because of microwaving) and you lose the data. You cannot "reapply" the reflector - the dye is destroyed with the original reflector thus wiping out the data.

For manufactured discs it is true that the data is cast into the polycarbonate. But, you would need to get at it. It is sealed up in a lacquer coating, of which most of that remains. You aren't going to re-coat the polycarbonate with anything left there and by "anything" I mean anything down to a size of around 100 nanometers. It would be impossible to "clean" the disc in a manner that would allow reapplication of the aluminum reflector.

The aluminum reflector on manufactured discs is applyed using a vacuum ion depositation technique. The layer is a few molecules thick. We are talking about a scale that most people can't even imagine it is so small.

Re:For those with less sense and less money

[Jane Q. Public]

It depends a lot on the design of the microwave. If it is turned on for any length of time with nothing to absorb the energy, that can, on some models, either overload or reflect back into (I am not sure which) the magnetron tube and damage it. Microwaves almost universally have a warning in the instructions to never run a microwave when empty, for that very reason. I believe the arcing caused by rings (or near-rings) of metal and certain other objects in a microwave -- including CDs -- is a different phenomenon. But once the CD is destroyed, if you continue to run the microwave you do run a chance of damaging it.

Re:For those with less sense and less money

[Jane Q. Public]

The microwave engineer's explanation is a little bit off. I'm not saying he is 100% wrong, but it is in fact rings of metal that are most dangerous, while continuous foils -- usually -- are not. Things like Hot Pockets, for example, have a bit of foil in the container that is used to reflect the microwaves.

However, if you put a continuous loop of metal in there, you can pretty much expect it to arc and possibly explode. It has something to do with forming a current loop, which cannot build up in a flat (non-loop) piece of metal. Near-circles, as the engineer mentions, are nearly as bad and will still arc because a small enough gap will still allow a current loop... the arc itself completes the loop.

And a metal object of any kind that is too near the metal walls of the microwave can cause an arc because of the energy differential between the two.

Re:For those with less sense and less money

[Jane Q. Public]

Good point about the sharp points and edges. Since charge builds on the surface of the object, any sharp point or edge will form a concentration of charge. I also wanted to mention again that rings or loops of metal should be avoided too.

Re:For those with less sense and less money

[Jane Q. Public]

Yeah, but that's not exactly easy to do. I've only managed it once so far. I think.

Re:For those with less sense and less money

[dgatwood]

However, I think it's easy to damage the microwave if you keep it running for too long, since the CD doesn't contain a whole lot of water that can absorb the energy.

Doesn't the glass plate at the bottom of the microwave absorb enough by itself to prevent damage? I thought that was the whole reason for having a glass plate at the bottom instead of just using bare metal.

Re:For those with less sense and less money

[0100010001010011]

Go to good will. "New" microwaves for $5. The damage I've done to one makes microwaving CDs look like childs play.

Re:For those with less sense and less money

[adolf]

That's not just newer microwaves, but ancient ones as well. The device you're speaking of is called, rather descriptively, a "stirrer."

My folks had a microwave made in the middle 70's that was so-equipped.

Other microwave ovens have a revolving glass platter, such as the Panasonic unit in my own kitchen. This simply rotates the item being microwaved, instead of rotating the microwaves.

All microwave ovens (well, at least the ones that cook food properly) have one or the other of these implementations. Properly designed, they behave equally well at distributing the microwave energy evenly across the item being nuked.

In terms of destroying the magnetron, all we care about is the relative orientation of the microwave energy, the item(s) inside (and their possible action as an antenna), and the walls of the unit. Either contraption will introduce sufficient noise to allow your handball analogy to work.

Myself, when I'm microwaving strange things for fun, I just make sure I leave a cup of water in there, with a bit of wood (toothpick, coffee stirrer, popsicle stick, bamboo skewer, etc) in the cup to prevent superheating (and possibly flash-boiling*) the water. This soaks up any radiation not already absorbed by the other item(s) in the microwave by converting it safely to heat.

Also rather boringly and commonly, the hole on the inside of my microwave through which the magnetron aims is covered rather tightly by a sheet of mica. Good luck getting something to arc through that. :)

*: A fun way to surprise the hell out of a friend, and quite possibly burn the shit out of their hands, arms and face is to fill a clean, smooth ceramic mug with water and microwave it until it is at a good boil. Then, stop the microwave, let the water stop boiling, and turn it back on for a minute or so. Then just ask your "friend" to remove the cup.

Re:For those with less sense and less money

[adolf]

Yep.

Which is why, when I nuke strange things in the microwave, I keep a cup of water in there as well (along with something wooden in it to act as a nucleation point to start it boiling). It soaks up energy that might otherwise find its way back to the magnetron.

Is it perfect? No. But it is good enough, in my experience: I've had the same microwave for 8 years, and it works just as poorly now as it did when it was new.

There is, of course, the odd chance that the thing I'm nuking will form a nice neat reflector and send a significant portion of the magnetron's energy back into itself before it can be converted to heat by the water. And standing waves, as you rightly describe, can be even worse.

But the revolving platter (or stirrer, in other models) will keep the duration of this reflection down to a very short duration, while also keeping the standing waves moving instead of possibly forming a particularly destructive, static pattern.

Unless I make a retroreflector out of metal and microwave that. Hmm....

Re:For those with less sense and less money

[JoeMerchant]

I think I saw a brand new microwave at Lowes last night for $35...

I'd be more worried about collateral damage like the vaporized metal and / or plastic getting out of the microwave and coating things I wouldn't want coated with that stuff, like my alveoli.

Re:For those with less sense and less money

[AndrewStephens]

... and is no more toxic than [...] wearing a gold wedding ring.

I have seen lives ruined this way - be careful out there.

Re:For those with less sense and less money

[RobertM1968]

Blow up? Not quite. Burn out? Yep. Semi-blow up? On older ones, yes - never tried it on newer ones. It's kinda like a capacitor "sizzling out" - it kinda sounds like a mini bug zapper for a second or two makes a muted pop-like sound, smells burnt and dies somewhat charred. Again, no idea if that still happens with newer ones, but I've done both the "burned out magnetron" and the "kinda blew up magnetron" route with older microwaves.

Re:For those with less sense and less money

[adolf]

I've got a couple of good-sized neon transformers here that I play with sometimes, and I must say that I sincerely doubt that they'd do anywhere near as good a job at neatly eroding aluminum as seen in the video.

In particular, they lack the overall anger that this 150,000 volt rig produces.

Re:For those with less sense and less money

[Neil Boekend]

The glas has an margin of a factor two for this job.

Re:For those with less sense and less money

[Joce640k]

The inside walls of every microwave I've ever seen are made of metal so I"m guessing it isn't bad.

The only time I ever worried about a microwave was when a piece of foil touched the inside wall and made a huge spark (and burnt the paint off where it touched). Apart from that I'm sure the disclaimers are mostly ass-covering and because you can't heat things up if they're inside a metal container (eg. a tin can).

Re:For those with less sense and less money

[Joce640k]

I thought it was so you can take it out and wash it when things spill.

{Yeah, I know. Real men don't do that sort of thing...}

Microwave

[yogidog98]

Science geeks have been doing this for years with microwave ovens; though, it was more for the cool light show than for data security.

First post?

[nomorecwrd]

Erased by lightning... it's Alive!! ^H^H^H^H erased!!

I find that fire works pretty well.

[John Hasler]

n/t

Heh

[MightyMartian]

150,000 volt transformer? Ah, now the ball’s in Farnsworth’s court. I suppose I could part with one and still be feared.

Re:Heh

[rgbatduke]

I have students that build tesla coils for extra credit projects every year or two, and have built one myself just for the fun of the big sparks. They generate ballpark of 150 kV at the top, and putting a CD on top so that you could watch the lightning arc out of it and craze the plastic and underlying metal was great fun. Naturally, at that voltage the plastic isn't exactly an insulator, so you get fractal lightning patterns almost instantly through the metal.

However, I wouldn't think of this as a way of technically erasing all of the data -- not erasing as in not all of the king's horses nor all of the kings men using NSA's resources can put it together again erasing. Erasing as in nobody is going to be able to put it in a stock player and scan any data off of it perhaps, but removing all of the actual physical encoding of the medium so that people cannot read off local patterns of information and apply information theoretic analysis to POSSIBLY reconstruct chunks of it? I don't think so. I'm not even sure that I'd trust scrambling or oxidizing all of the metal for that -- the plastic alone might contain enough structural alteration that a very sensitive molecular-level scan could pick up patterns, if you have a few tens of millions of dollars to use trying (NSA money, in other words).

But simply breaking a CD or DVD in two is probably enough to stop all but the most dedicated and well-equipped would-be data thief. There would have to be a strong incentive to spend real money to reconstruct even that.

With that said, I agree with the individual above who said fire. Fire takes care of all of the information, whether it is cooking in a microwave or conventional oven or in a real fire with real wood outdoors. Because of the toxins given off by burning plastic, I like outdoors. Not even the NSA could reconstruct information from DVD ash, or even (realistically) from the blob of molten plastic you'd get even before you turned the DVD to ash and then blew the ash into the air as a fine powder or washed it into the dirt. Fire is raw entropy.

rgb

Fire?

[linuxguy]

What, throwing it in fire wouldn't have worked?

Re:Fire?

[ArundelCastle]

Fire is antiquated, wasting precious oxygen and leaves a carbon footprint. Electricity is something that anyone with enough CDs to bother erasing is already paying for. ;)

Re:Fire?

[arth1]

Even simpler: A few swipes with sanding paper on the print side.

Please...

[mrbcs]

Just break the damn things.

Re:Please...

[Loether]

I agree. While most people do have a handy microwave, even more have a handy trash can. I always turn my head away and close my eyes and snap that sucker in half in the trash can. Works every time.

Re:Please...

[AlienIntelligence]

Just break the damn things.

You do realize destruction != "secure destruction"

I believe it actually states the MOST SECURE in
the post.

-AI

Re:Please...

[MichaelSmith]

Its in the metal, otherwise the metal would not be required.

Re:Please...

[amicusNYCL]

I believe it actually states the MOST SECURE in the post.

Which, as well all know, are never wrong and always 100% accurate.

What's wrong with just burning them? Why would someone ever want to waste 150,000 volts to erase a little bit of data on a single disc when you could erase as many as you can toss in for the low, low energy cost of a single burning log?

Re:Please...

[catmistake]

Isn't the data actually stored in the plastic, rather than the metal?

So wouldn't recovering the data just be a case of putting something reflective on the back of it? e.g., placing a blank CD on top of the erased one.

No. The data is stored on tiny pips and pits in the metal.

Re:Please...

[Anonymous Coward]

Nope, the metal is a reflective layer allowing the pits in the plastic to be seen by the laser.

http://electronics.howstuffworks.com/cd1.htm

Depending on this top acrylic layer; it may be that depositing a new metal layer on the top of the disc will allow this to be read again.

CD-R have the data stored in the dye layer, the metal is just a reflective surface

http://computer.howstuffworks.com/cd-burner4.htm

Re:Please...

[Anne_Nonymous]

A few hits with the claw end of an Estwing, and they delaminate pretty effectively.

Re:Please...

[Dogtanian]

What's wrong with just burning them? Why would someone ever want to waste 150,000 volts to erase a little bit of data on a single disc when you could erase as many as you can toss in for the low, low energy cost of a single burning log?

Er, I believe that I'm stating the bleeding obvious here when I say "because it's cool and fun".

Really, did you seriously think the guy was doing it that way for any other reason, or seriously suggesting it as a practical solution to your disk-wiping needs?!!

Re:Please...

[JonySuede]

You have it backward with regard to the energy cost. You see you have 150 000 V * 0.001mA *25s and for a typical 1kg wood log (assuming total combustion) you have 18 MJ/kg * 1kg and according to wolframalpha 150000 V * 0.001mA * 25s 18 MJ/kg * 1kg = true

Re:Please...

[bxbaser]

yes you could put a new reflective layer on the plastic and read the pits if it is a commercially produced cd, a recordable cd has the data in the dye layer.
all you need is a high vacuum chamber with an aluminum sputtering source

Re:Please...

[Nethemas the Great]

Yes, the data is stored in the polycarbonate layer. The foil provides something to bounce the laser light off of. The question is does this process melt the pits in the plastic while stripping the foil off? Microwaving them melts the plastic, this process seems a bit too precise for it to effectively affect the data. While "cool" factor is high "secure" factor is low.

Re:Please...

[amicusNYCL]

You forgot to factor in the number of discs destroyed via current (1) versus the number of discs destroyed by the log, and calculating the energy cost to destroy per disc. I'll leave the number of discs that a 1kg burning log can melt as an exercise for the reader.

Re:Please...

[Hatta]

What's the fun in that?

Re:Please...

[JonySuede]

I must admit that you are true, you can achieve a more efficient destruction with the log if you scale the process up.

Re:Please...

[cdrguru]

Someone not too long ago thought that would work. The US Secret Service broke in on them and from across the room the guy said "You aren't getting this one!" and broke a disc in half.

The Secret Service called us and asked what could they do? We told them a couple of interesting techniques for putting a snapped disc back together and sent them a trial version of our software to assist with the task. An hour later they called back and ordered four copies of the software and never said another word about what the result was.

Do not count on breaking a disc in half. It isn't anywhere near good enough. If you get the pieces below about 1/8th of a disc I think you probably are safe, but you have to get all of the pieces this small.

Also, be very careful breaking discs. They tend to throw off microscopic pieces of polycarbonate which are very, very sharp.

Re:Please...

[Neil Boekend]

It would kind of suck if you had a printed disk you would like to destroy securely, since there are probably literally thousands of disks with the same data. A CD-R is more like to require destruction.

Re:Please...

[Stone2065]

If you folks SAW what a microwave zapped CD looks like afterwards, you would realize that first of all, there are gaps of a few millimeters in the silver, plus any dye sandwiched in the poly, would cook/vaporize during the zapping, so it's kinda moot as to where the bloody data IS stored on the CD...

Re:Please...

[bronney]

was that in log scale?

Re:Please...

[geekoid]

Freeze, hit with hammer.

I mean, there is a point when all other efforts are just wasteful. I could say, toss it in a black hole is th most secures. I would be technically correct, but is it really more secure then throwing it in the sun? or shattering it into 1000's of pieces?

OTOH: technically correct is the best kind of correct~

Re:Please...

[AlienIntelligence]

Freeze, hit with hammer.

I mean, there is a point when all other efforts are just wasteful. I could say, toss it in a black hole is th most secures. I would be technically correct, but is it really more secure then throwing it in the sun? or shattering it into 1000's of pieces?

OTOH: technically correct is the best kind of correct~

While I realize a response wasn't necessary... one thing to consider about security
is the chain of custody. I think a launch to a black hole would leave a 'small' gap in
the chain of custody.

While the fire ideas are valid... I think something could be said for completeness of
destruction vs time.

That time would also scale pretty quickly the more cd's you dumped in the fire.

A machine that had 10 x 10 of the electrical "cookers" would be able to do 100 discs
in exactly the same time as the 1. Whereas burning, would require a scale of a fuel.
Thus a scale in time. Where at some point you would not be able to scale it anymore
efficiently.

Of course, this avoids the concept of industrial incinerators... or smelting plants.

I personally think a 1000 of these dropped in a smelt bucket, or dropped in with the
slag, would see a timely death of a few seconds.

-AI

Re:Anyone heard of a microwave?

[MightyMartian]

The exact same thing will happen if you put a CD in the microwave for about 2 seconds... I'm not sure what happens to the microwave if it goes longer, but I hear it's bad./blockquote?

Bad as in "my wife's gonna kill me for fucking up the microwave" bad? Or are we talking "Tokyo's completely fucked" bad?

Re:Anyone heard of a microwave?

[f8l_0e]

Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light.

Sandpaper?

[Labcoat Samurai]

It's certainly cheaper.

Re:Sandpaper?

[Plekto]

Beat me to it. The important surface on a CD is the "side" with the label on it. A few seconds with sandpaper does very easily solve any issues. Note - with something more complex like a dual-layer DVD, you have to destroy the actual disc to get at the second layer.

Nice (expensive) toy, but destroying CDs is stupidly easy.

That...

[AlienIntelligence]

That... was one of the coolest electricity displays I've seen in a long time.

Ta heck with what it does, lol

-AI

Re:That...

[ArundelCastle]

How did 150,000 volts not explode a 9V battery?

Re:That...

[Pingmaster]

The 9V battery probably saw precisely none of that voltage. Chances are, the way it was set up is to put 75kV on one post and -75kV on the other, giving a potential difference between the posts of 150kV. The electricity then arced from one post, through the metal in the CD, to the other post because the metal provided a path of less resistance than the air over the CD. Once the metal was gone from the CD, it arced though the chassis of the motor mostly (from what I could see). There was no reason for the arc to pass through the battery terminals since the chassis provided a much shorter path.

Now, had they placed the battery in line with the arc, that probably would not have ended quite so well...

wha?

[Charliemopps]

Most secure? My ass...
The microwave
A Fire
Paper shredder
Acetone
This is just an expensive toy

Re:wha?

[ZosX]

lots of ways to destroy a plastic disc with metallic coating. i kind of agree. there is the relative small risk in shreading that they can somehow reconstruct a disc, but even then they wouldn't have anything near a complete image. nope, i'd say about 3-5 seconds in the microwave is about the quickest and easiest way to nuke a cd.

Re:wha?

[MichaelSmith]

A Fire

A friend of mine lost his house in the 2009 brushfires here in Victoria. He had a fantastic and very valuable music collection. After the fire he went back with his partner and looked through the wreckage. They found nothing remotely resembling a CD.

Re:wha?

[kikito]

I use my bare hands. Feels very macho.

Re:wha?

[confused one]

polycarbonates make wonderful fuels. They can be used in solid rocket motors, if mixed with a suitable oxidizer.

Re:wha?

[quacking duck]

Finally, something to do with all those junk AOL CDs!

Re:wha?

[cdrguru]

Fire isn't all that great unless you really get the disc up beyond the glass point of polycarbonate, which is around 230C. You can degrade the dye of recordable discs starting at 120F, but that isn't going to assure unreadability.

Turning the disc into a bent, folded mess is OK, but unless you go that far it isn't going to work.

Some folks had a fire and we were called on to evaluate the readability of the discs. Of the 30 or so they sent us, all but two were fine, even one with clear smoke damage to it. The guy was trying to claim thousands of dollars in lost software because of the discs. Upon getting the report it seems they settled with the insurance company for a lot less.

Remember, the drive is important. Just because your crappy drive can't read it does not mean a good drive can't. Sadly, there are very few good drives available.

Re:wha?

[Neil Boekend]

If I remember my mythbuster episodes correctly the form they used for rocket fuel was in a thick walled pipe (from salami or carbon-laced candle wax): the hollow inside was used to conduct the oxidiser. A stack of CD's already has this configuration, so you could simply stack a lot of them in a 10 cm inside diameter steel tube, add a graphite nozzle and be happy.
IANARS

Re:wha?

[pz]

This is just an expensive toy

An expensive and dangerous toy! But so much fun!

Re:wha?

[confused one]

Yep. Just pump in NOx or LOx, add spark, and you're off.

Oddly complicated

[Geoffrey.landis]

Seems an oddly complicated way to do it. Just put it in the oven at 350 F for a few minutes. (175 C, for the metric users).

Re:Oddly complicated

[aaronjp]

Maybe, but it is erasing with style!

Re:Oddly complicated

[MichaelSmith]

175 C, for the metric users.

Whats the temperature for a fan forced oven? I always get that wrong.

Re:Oddly complicated

[msauve]

"Whats the temperature for a fan forced oven?"

African or European?

Re:Oddly complicated

[Dolphinzilla]

+1 Funny Monty Python reference

Re:Anyone heard of a microwave?

[sqlrob]

Right. That's bad.

will it blend?

[YrWrstNtmr]

Who doesn't have even a cheap shredder? Even my $40 OfficeMax shredder turns CDs into .125" pieces. Need more than that? A DoD shredder for Secret and above turns them into CD dust.

Is this really secure?

[Zorpheus]

Of course you can not read a CD if the reflective metal layer is removed. But the data is stored in tiny pits that are printed into the polycarbonate layer. If the polycarbonate is not damaged too much, the CD might be readable when a new metal layer is applied.

Re:Is this really secure?

[amicusNYCL]

That only applies for pressed discs, not writable ones.

Re:Is this really secure?

[pbjones]

nice to see that someone else knows about his. A couple of strokes with 60 grit emery paper will also make them unreadable, and you can keep a piece in your desk draw.

Here's an idea

[Nidi62]

Just set up a board on some trees(or find a nice wooden fence) nail a bunch of CDs up there, and go to town with some deer slugs or other high caliber ammunition. Or, if it's almost duck, dove, or quail season, put the CDs in their cases and you have yourself some free skeet.

Re:Here's an idea

[vlpronj]

I would think for thoroughness, the smaller projectiles of birdshot would be better than slugs.

Re:Here's an idea

[Nidi62]

But the holes from a slug would be bigger, and it gives you an excuse to shoot at them even more :)

Woah

[cuckundu]

I was going to make a disparaging remark about how you could just break it, but then I actually watched the video and now I want one

Lots of easier ways

[blitz487]

Or do what I do. Rub it face down on the concrete, like the sidewalk.

Microwave + CD = Fun!

[GnomieHomie]

Just put about 5 of them in the microwave and watch the fun happen.

Flashy but not secure

[Fry-kun]

The metallic reflective layer is NOT where the information is stored, it just aids in the information retrieval. In other words, this method might not destroy the data at all. It's true that it's pretty hard to get the data back, but depending on various conditions it may not be impossible.

Re:Flashy but not secure

[michaelmalak]

The metallic reflective layer is NOT where the information is stored, it just aids in the information retrieval. In other words, this method might not destroy the data at all. It's true that it's pretty hard to get the data back, but depending on various conditions it may not be impossible.

Indeed, I can imagine a CD data-recovery player in the future that analyzes non-reflective surfaces with high-resolution lasers or other imaging, just to recover data from aged CDs. Kind of like the laser-based record-players today. And I imagine such a player available at consumer prices.

Re:Flashy but not secure

[Darinbob]

This is true for a manufactured CD. The data will be actually encoded using physical bumps. But for recordable CDs which are typically the only type where you care about erasing, the sparks or microwave should do a good job of messing things up.

Most secure

[kaoshin]

The most secure way to destroy CDs is either dissolving in acid or loaning them to my boss. I promise, you'd never see it again.

Re:Most secure

[kitsunewarlock]

You can get most of the information from your bosses Youtube and Flickr account. And he'd like to see you in his office about what couldn't be posted on those sites.

Easiest way

[reboot246]

Just give it to a three year old to play with for a while. Even the NSA wouldn't be able to get any data off of it!

Re:Easiest way

[Abstrackt]

And people wonder why all my DVD cases are filled with copies instead of originals.

polycarb plastic?

[vlm]

Its polycarb plastic, right? Expose it to a chlorinated solvent and it'll craze and crumble, kinda de-polymerize itself. Breathing the vapors is inadvisable.

erasing

[Bizzeh]

this isnt so much erasing as it is, melting...

Two Words

[hilldog]

Skeet Shoot

Toxic vapor ?

[billcopc]

I'm no chemistry whiz, but wouldn't this result in a lot of vaporized aluminum in the air ? Doesn't sound so great for the old lungs, no...

Nonsense

[Santheman]

I've used one of these for years in a SCIF. http://www.whitakerbrothers.com/datastroyer-101-cd-high-security-shredder

Since the real data is not burned in the metallic

[Anonymous Coward]

I don't really think that method erased the data on the CD.
What happened is that the electrical charge evaporated the metallic layer of the CD. Since the real data is not burned in the metallic layer, it still available (but unreadable).

The data is stored in the polymeric layer inside the plastic, and the metallic layer function is only to reflect the laser bean.
In theory, if you can coat a new metallic layer on that electrical charge erased CD, you could read the data again.

Grongo

Most Secure vs. Good Enough

[geekmux]

"...This may be the most secure method to remove data on conventional recordable CDs used in offices."

Sure, this may be "the" most secure method, but there are plenty of other methods that fall easily into the category of "good enough" (microwaves, shredders, even breaking apart by hand). Kudos for the geek factor with all this, but realistically this is a solution without a problem.

Re:Most Secure vs. Good Enough

[XiaoMing]

Just watch as I re-extract half of all the data from every CD that the device has ever wiped from what was electroplated back onto the cathode...Secure, my butt!

Re:Most Secure vs. Good Enough

[AbrasiveCat]

I find an arc furnace does a fine job on CDs, DVDs, and conventional hard drives. The data seem unrecoverable from the dust and ingots left behind.

Labels?

[TavisJohn]

What if the CD has a label on it.
Will that effect this process?

Re:Labels?

[TavisJohn]

Oooo Way to go being a grammar/spell-checker...

And thanks for not actually contributing anything also!

English Nazi. :p

Re:Labels?

[black3d]

What's especially amusing is that effect could also be used in that sentence, both in relation to the creation of the "effect" and also "effect" the process - make it possible. Although I think you MEANT affect, he really was very narrow-sighted to grammar-nazi it. He should have instead replied as if you did indeed mean effect.

Star Wars

[U8MyData]

Is it only me or does this remind some of the Emperor's line, "Now you will witness the full power of the Dark Side!"

It's not the volts

[BenSchuarmer]

it's the amps

Re:It's not the volts

[nzac]

But without the volts there would be no amps.

According to the article its the power as in P=VI that matters anyway.

Re:It's not the volts

[pclminion]

it's the amps

And it's not the fall that kills you, it's the sudden stop at the end. Except you don't get that sudden stop without falling. And you don't get current without voltage. It's a cute little saying but it doesn't actually say much.

What's wrong with a box cutter?

[srodden]

A few slashes from a box cutter on the label side and the reflective surface strips off, taking much of the organic dye with it and butchering the substrate. Only the most dedicated would be able to get meaningful data from that disc.

Re:In The Ghetto, 01-10.

[telekon]

what is this i dont even

Media shredder

[NiceGeek]

At my old job we bought a decent cd shredder. I think that pulling data off of hundreds of little bits of CD would be pretty secure.

Re:In The Ghetto, 01-10.

[telekon]

More to the point, how is the the entire internets turning into 4chan?

Github, Reddit,^H^H^H^H^H^H^H Slashdot... the sewer is overflowing.

Better way

[NicknamesAreStupid]

Plasma gasification, after a few seconds at 14,000C, there is not much left. Even works with BluRay(R), and you do not have to pay Sony.

Re:Better way

[hypertex]

When pre-recorded CDs first came out I noticed that one could tell where the data ended. Only about 2/3's of the disc was used and I thought it would be slick to write the name/logo in this space. So I would place the CD on a plasma globe and position the blank area over a large plasma streamer. With the use of an insulated dental pick or small screwdriver, I was able to draw the plasma stream out of the globe through the CD, vaporizing the aluminum.
Kids: don't try this at home. You've been warned.

Recycling?

[Yvan256]

Would that help with recycling CDs and single-layer DVDs?

Re:Incinerator?

[Greyfox]

What, like Winston Smith? Didn't work very well for HIM, did it?

More secure data erasure (video)

[BadPirate]

To be as certain as possible that all data is irretrievable I always toss my CD's into a black hole. (Video - http://www.youtube.com/watch?v=8tPnX7OPo0Q)

Shredder

[nurb432]

Is pretty damned effective since the plastic shatters as it is cut ( unlike paper ). And if that isn't enough for you, burn what is left over a open fire, with some marshmallows.

Security goes a long way...

[lalcan]

Using "150,000 volt" and "most secure method" in the same article really made my eyebrows rise...

I kept waiting for someone to shout ...

[QilessQi]

... "IT'S ALIIIIVE!!!!!!"

Fire solves all problems.

[Amyntas]

Most secure?

Burn it. End of story.
Nobody is likely to be extracting your precious data off a melted glob of plastic covered in carbon.

As an alternative, for those who are ambitions... Shred it, shred it again, microwave the shreds, then burn the microwaved shreds as well as the microwave. ( if it has not already caught fire )

It's a trifle cheaper to just burn it. @_@

Re:In The Ghetto, 01-10.

[IonOtter]

Congratulations.

You have just met the GNAA.

You may cry now.

Re: One Word

[Lvdata]

Miss

Shredder, Incinerator

[Katchu]

Not much better than sending CD through a shredder or through the incinerator in the burn-bags. Of course, not as fun to watch.

To totally render a disk unreadable,,,,

[arsemonkey]

Hand it to a toddler for about 2 seconds. Ask anyone who has one.

But How fast do you destroy the Microwave?

[billstewart]

Ok, microwaving CDs is fun, but how do you make sure you don't trash the microwave in the process? (Putting a cup of water in along with the CD helps, but I'm not sure if it does the whole job if you're doing this kind of thing repeatedly.)

More important, is it safe to use the microwave for food after zapping CDs, or could there be chemicals in there you don't want in your food? Do you need to have a separate microwave for trashing electronics?

Re:But How fast do you destroy the Microwave?

[Stone2065]

I've found, by killing many CDs this way, that 3 seconds on an 800watt microwave is just about right. I would say 2 seconds on a 1000watt, and the 5 seconds mentioned earlier for the little 500-750watt dorm style ones. Ever look at a CD that's been zapped that way? Looks REALLY cool both during and after, and no way in HELL will data still be there, nor the CD be useable for data storage ever again.

Re:But How fast do you destroy the Microwave?

[Joce640k]

Why would it trash the microwave?

Microwaves smell pretty bad after zapping CDs. I always put kitchen paper underneath to catch all the residues that they leave behind.

Re:But How fast do you destroy the Microwave?

[RockDoctor]

is it safe to use the microwave for food after zapping CDs, or could there be chemicals in there you don't want in your food? Do you need to have a separate microwave for trashing electronics?

Reasonable question. It's been a while since I burned a disc (and longer since I felt a need to nuke a disc), but the smell is pretty offensive. Even if the fumes are harmless, the smell is an adequate reason.

If I wanted to do it again, I'd probably put the CD inside a disposable (e.g. takeaway food) container which seals loosely and will provide a surface for any nasty chemicals to condense onto. Cup of water too, of course.

I don't know if it would work with the CD immersed in the water - feel free to experiment.

Re:But How fast do you destroy the Microwave?

[Golddess]

Why would it trash the microwave?

When I was a kid, I put a metal cupcake tin in a microwave. There was a bright flash, a loud noise, and the microwave no longer worked.

I know it's possible for some metallic objects to be used safely in a microwave, but after that experience, I'm a little weary of trying it again.

Toxic Fumes in your Microwave?

[billstewart]

So how safe are the gaseous and particulate byproducts of microwaving or otherwise zapping CDs? Is it safe to do this indoors? Is it safe to use the microwave for food after using it for this sort of entertainment? Are CDROMs known to the state of California to cause cancer and sudden growth of extra limbs?

Re:Toxic Fumes in your Microwave?

[Stone2065]

All of the CDs I've zapped in a microwave was done on the one in my kitchen. No weirdness occured, i.e. smells, tastes in food, smoke, etc. For max cool factor, before you hit "start", kill all the lights in the kitchen, the light show is quick, but VERY cool. :)

You're All Doing It Wrong!

[VortexCortex]

I'm sorry -- I've read most of the above posts, and they are ALL doing it wrong.

So, how do I destroy sensitive data that's stored on a CD (or any other storage medium for that matter)?

I forget the decryption key. Storage medium stays INTACT -- Can even be reused if it's re-writable. Uses the least amount of energy, causes the least amount of pollution.

Look, if the data is precious enough that it warrants complete destruction at some point ENCRYPT IT YOU FOOL!

I use a key-ring based approach: The decryption keys are encrypted with my personal pass-phrase. This allows me to change my password without re-encrypting all of my data ( just the decryption keys for them ). Overwriting the decryption keys 1000 times with random numbers ensures that I can't be tortured into giving access to the data once destroyed this way -- I don't know what the actual decryption keys are, just my password that unlocked them.

Re:You're All Doing It Wrong!

[ThatsMyNick]

What if Quantum computers become a reality? You puny scheme will fail!! The one in TFA will hold as long as no one discovers time travel (and a specific form of time travel, at that).

Blendtec.

[bronney]

Why no one mentions baffles me.

Recordable CDs?

[Joce640k]

Just scratch the silver stuff off with some scissors. It comes off really easily.

Or get an old ballpoint and draw some squiggles on it while pressing hard. It totally wrecks the recording layer.

Re:In The Ghetto, 01-10.

[Joce640k]

Seemed just like the old alt.tasteless to me.

Re:piece a shredded item back together again.

[Joce640k]

Have you ever seen how easily the recording surface comes off a recordable CD? Try scratching one with your fingernail sometime. There's no way anybody is going to piece it back together after going through a shredder.

nb. DVDs are different - the recording layer is in a sandwich between two layers of plastic.

Pretty cool demo.. but

[Combatso]

I have found the best way to destroy recordable CD's is to keep them in protective cases, store them carefully, and then POOF they are unreadable when I go to use them.

Way more effective

[bobvious]

Right. This is way more secure than burning them in the fireplace.

Shredders FTW

[flibbidyfloo]

I'm not the first here to mention shredding, but I don't get the confusion over "re-assembly". I have a $70 home crosscut shredder that can shred a CD/DVD. the result is a fairly fine powder that looks a lot like glitter. Run a couple discs through it and let it mix with the paper shredded too and it's not really the sort of thing someone can piece back together, even with an electron microscope.

Re:piece a shredded item back together again.

[geekoid]

yes, but a DVD recording layer will still stretch and tear as to be impossible to put back together. SO shredding it destroys the data.

Re:In The Ghetto, 01-10.

[telekon]

Have you seen my user id? Not that new.