Easiest and safest way to make cd unreadable?

I have some CDs and DVDs that need to be thrown away. They contain sensitive data about myself and must not be recovered. Now, i've read many articles and tips, scissors, microwave, break them in half, melt, burn... but they are somewhat dangerous and/or tedious to do for many CDs. I'm lookig an easy and safe way to make them unreadable. What I would prefer is to scratch them using a cutter, a small cut at a precise location and would kill it. But that does not work very well as some files are still recoverable.

Any thoughts?

Thank you

breaking them seems the most simple solution - then they could be recovered only by forensic labs - what are the odds of them going though your or public garbage piles, collecting broken media pieces? pretty much none worth mentioning

besides, all the things about you are already known, way before you even started experiencing them (for the answer see my sig hehe)

Once I had to throw away several cds and dvds so I broke them one by one, it's repetitive work and sometimes hurts the hand, since the pieces become sharp.
I remember once I saw a CD/DVD shredder that worked pretty much like a paper shredder, but I don't know if it's easy to find nor the price.

burn them

Manually breaking the discs into pieces is the simplest and most effective method. Always wrap them in a towel first, to keep your hands and eyes safe. To accelerate the process, you could snap each disc just once, then insert the halves into a blender and run it at full power for some seconds at a time. Then throw away only a few of the remains every day, if you want to be extra-careful...

Other ideas:

• Burning or dissolving with acetone. This should be done in open air locations, as the resulting fumes may be dangerous.
• Microwaving them for five seconds. They will uniformly crack with a neat maze-like pattern. This also requires good ventilation, as well as careful handling of discs after they undergo the process.

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Originally Posted by alpacino

I remember once I saw a CD/DVD shredder that worked pretty much like a paper shredder, but I don't know if it's easy to find nor the price.

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I have seen those too. Insert a disc and they'll either crunch it into pieces or scratch every milimeter of it, so that any sort of recovery is impossible.

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I remember once I saw a CD/DVD shredder that worked pretty much like a paper shredder, but I don't know if it's easy to find nor the price.

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I have seen those too. Insert a disc and they'll either crunch it into pieces or scratch every milimeter of it, so that any sort of recovery is impossible.

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I had one of those at work, very effective. Turned them into small, thin shreads. But we don't have them anymore.

While I do appreciate the suggestions, I was looking for something else.
How about fixing an old CD-ROM drive to scratch the entire surface?

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Originally Posted by anon

• Microwaving them for five seconds. They will uniformly crack with a neat maze-like pattern. This also requires good ventilation, as well as careful handling of discs after they undergo the process.

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Would you ever use this microwave oven again for food? :D

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Originally Posted by Master Razor

How about fixing an old CD-ROM drive to scratch the entire surface?

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This might be doable with some tinkering and if you can get the drive to "read" all of the disc, but I've never heard of such a thing. While we're at it, increasing the laser's output power to the point it damages discs would probably also work...

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Originally Posted by alpacino

Would you ever use this microwave oven again for food? :D

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I wouldn't use that method at all. My post was purely for educational purposes :gredface:

I used the microwave method some time ago, when I had to destroy 20+ CDs

"Ride the lightning"

i disposed of over 1000 cds and dvds a few years back.

i just broke each one by hand - they almost never snap straight in two - the discs usually shatter into a few big and a bunch of little pieces. 30 seconds in i grabbed a big trash bag, and each time i picked up a disc, i would hold it inside the bag, snap it (wincing every single time lol) and then grab the next one. you wont need gloves as the plastic is brittle, but i do recommend holding them in a large trash bag like i did, or tiny pieces of plastic will be flying everywhere (and could also get into your eyes if you're unlucky).

i broke all the discs this way in about 2 days (that wasn't continuous!) - it's easy but tedious and your hands can ache after a while. if you're disposing of a large quantity of discs, you can easily mix and then split the fragments between numerous bags before throwing them into different trashcans.

originally i did want to burn them, but i didn't have anywhere to burn that quantity of trash...

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i just broke each one by hand - they almost never snap straight in two - the discs usually shatter into a few big and a bunch of little pieces. 30 seconds in i grabbed a big trash bag, and each time i picked up a disc, i would hold it inside the bag, snap it (wincing every single time lol) and then grab the next one. you wont need gloves as the plastic is brittle, but i do recommend holding them in a large trash bag like i did, or tiny pieces of plastic will be flying everywhere (and could also get into your eyes if you're unlucky).

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That is my current method as well. In large garbage bag it works quite well.

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Originally Posted by takomania

i just broke each one by hand - they almost never snap straight in two

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My experience is that they'll either break instantly or bend like cardboard, and in the latter case you'll have to "pinch" the bent area to snap them. This likely depends on the brand and manufacturing quality.

My experience was similar, I used to stick my hand with the disc inside a big can of thrash in my house and break them. Some would snap right away in pieces, some in 2 pieces and some would just bend (usually the pressed and original ones).
I remember I disposed 3 CD game called Morrowind that came with a Geforce 3 Ti I owned a long time ago. Now last year a friend of mine was looking for those because someone is making a mod where you can play this Morrowind with the Skyrim engine or something like that.

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Originally Posted by alpacino

I remember I disposed 3 CD game called Morrowind that came with a Geforce 3 Ti I owned a long time ago. Now last year a friend of mine was looking for those because someone is making a mod where you can play this Morrowind with the Skyrim engine or something like that.

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Relax, I'm sure "backup copies" of the game can be downloaded with ease :shifty:

Morrowind seemed like a good game, it was a fusion of a fantasy world with GTA. I had it and the two expansions, but I just couldn't get into it, it was perhaps too free and non-linear (excessive choice can be a problem).

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My experience is that they'll either break instantly or bend like cardboard, and in the latter case you'll have to "pinch" the bent area to snap them. This likely depends on the brand and manufacturing quality.

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Exactly. I'd say it depends on the batch process. Had 3 CDs, same manufacturer, one broke easily, while the other two just bent.

While we are on the subject, does anyone know why some CDs are very transparent-like and you just see through them? Windows DVDs, audio CDs, etc. are somewhat thicker and cannot see through them while blank recordable disks are thinner and transparent. Why is that?

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Originally Posted by anon

Relax, I'm sure "backup copies" of the game can be downloaded with ease :shifty:

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Oh yes, sure! :D. But what I forgot to mention is that this friend of mine is an exhaustive video-game collector, so just imagine his frustration.

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While we are on the subject, does anyone know why some CDs are very transparent-like and you just see through them? Windows DVDs, audio CDs, etc. are somewhat thicker and cannot see through them while blank recordable disks are thinner and transparent. Why is that?

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Isn't it because those Windows and audio CDs are pressed? I mean the way they are manufactured, making them thicker and more resistant.

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Originally Posted by Master Razor

Exactly. I'd say it depends on the batch process. Had 3 CDs, same manufacturer, one broke easily, while the other two just bent.

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I resumed my cleanup today, and ended up breaking three discs, two Verbatim and one brandless. The first Verbatim (white label) snapped instantly, the other two bent like paper and required pinching and bending on the opposite direction to be broken.

:unsure:

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While we are on the subject, does anyone know why some CDs are very transparent-like and you just see through them? Windows DVDs, audio CDs, etc. are somewhat thicker and cannot see through them while blank recordable disks are thinner and transparent. Why is that?

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Originally Posted by alpacino

Isn't it because those Windows and audio CDs are pressed? I mean the way they are manufactured, making them thicker and more resistant.

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Even blank media aren't all the same in this regard. I guess it depends on the quality and/or thickness of label, reflective layer or both. The worst offenders are virtually transparent when held in front of a light source.

Don't get me started on those very cheap discs which had no label at all, making both sides look the same. I used to put a sticker on the non-recordable side to tell them apart... stickers like "side A", "side B" and numbers from 0 to 9 which came with blank cassettes.

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Don't get me started on those very cheap discs which had no label at all, making both sides look the same.

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i remember those. I used to love them as kid, but I never could tell apart one from the other.

I found something interesting that just never occurred to me.
compact disc - Why do CDs and DVDs fill up from the centre outwards? - Super User

Since cd/dvd/blu-ray writers all read from the center of the disk to outwards, why not just scratch the exact starting bit of the disk? If you scratch the filesystem, which always start at that point, wouldn't you render the disk unreadable?

^nope

the data would be unreadable to regular people, but if you're talking about forensics, it's no different to blowing away partition tables on a hard drive - the data is still there, it's just not readily accessible.

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Originally Posted by Master Razor

Since cd/dvd/blu-ray writers all read from the center of the disk to outwards, why not just scratch the exact starting bit of the disk? If you scratch the filesystem, which always start at that point, wouldn't you render the disk unreadable?

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The result would be the same as quick-erasing rewritable media: the disc will appear to be empty (or unreadable), but the fact the actual data remains on it and is completely contiguous makes it highly vulnerable to file carving. And if you're picturing some dudes in lab coats working in a clean room, it can actually be done with a pirated copy of WinHex in a few minutes' time.

And who knows, maybe a long ddrescue session would even be able to read the scratched area. Two years ago I managed to completely recover some CDs that looked like they'd been used as knife sharpeners. It took several days, but I got it done.

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Originally Posted by anon

And who knows, maybe a long ddrescue session would even be able to read the scratched area.

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no need (depending on the disc type). forensics can easily separate the layers of the disc and rebuild using new plastics. i don't know if it works with pressed discs, but it definitely works with burnt cds/dvds/gds etc.

you'd have to scratch deep enough to destroy the dye platter on the disc, below the plastic.

In other words, breaking them into little pieces remains the most effective way! :wgrin: