Magnetic Mayhem

I am preparing to move this month and have been going through all the old computers my sister and I have accumulated while staying together. There were a total of seven needing disposal. One got sold at a garage sale and the other six were disassembled and recycled.

The main concern though when getting rid of old hardware is the magnetic media. What happens to the hard drives and the data on them? If you throw them away, they can be picked up at the dump, mounted in a new machine, and searched. Your data is still there. Formatting your drive or deleting your files won’t solve the problem. All that does is remove the FAT (File Allocation Table) data. The actual file is still there and it is pretty easy to recover. Personal data such as passwords, e-mail, credit card numbers, social security numbers, tax data, the fact that you are a closet Hello Kitty fan… it’s all there for the taking.

So how to destroy it? The simplest way is to do a data wipe. My favorite tool is called Darik’s Boot and Nuke (DBAN). It comes as an ISO file that you have to burn onto a CD, then you boot from the CD, and choose your options. I usually just type DOD and go read a book. The program then writes over the entire surface of the drive seven times. No basic criminal is going to bother trying to get your data back from that. The only guys who have the resources to get data back from that have expensive labs at their beck and call. Criminals don’t have that.

Don’t wanna do that? Let’s try something else then.


In my move preparations, I found four more leftover hard drives that needed destruction. Pictured above are three old Western Digital drives, and behind my eager assistant, is an unmarked drive which we think may have been an IBM DeskStar, but we really aren’t sure.

The Plan? Disassembly. I’d rather take them outside and burn a bit of thermite on top of them, but I imagine that something like that would be illegal, or at least frowned upon by the neighborhood association.

The Tools: Screwdrivers – with a set of hex heads.

The bottom of the hard drive has some screws holding a circuit board to the main body. You can leave that there. If you want to though it comes off easily. Only screws hold it on. The printed circuit board only has contact connections to the body – no wires.

The top screws are what you need to remove. Some of the screws may not be obvious. Two of the Western Digital drives had screws hidden under the labels. These are old drives, but they do this on newer ones as well.


On these older drives I found a feature I hadn’t seen before. After the screws had been removed there was a metallic tape around the edge of the drives’ top plate. If your drive has something like this, just find the end of the tape and pull it off. Don’t worry too much about the voided warranty warning. We’re destroying the drive anyway.


Once you get the top of the drive off, you have access to the guts of the drive.


If you are into just destroying your data, right now you can do all kinds of stuff to the actual hard drive platteres themselves. Me, I start taking everything apart because there are some cool bits inside these things. The shiny metal platters themselves could make some nifty “code ninja shuriken” is you have the tools to work aluminum. The platter retaining rings and spacers I give to my sister so she can make geek bling jewelry. The really cool stuff though is under the metal bracket. REALLY powerful rare earth magnets! Fun stuff if, like me, you never grew up.

If you were more serious about data destruction, take the platters and shred them (somewhat difficult as they are metallic) or go at them with a blow torch. A propane torch flame can exceed 1900C and if the platter is heated to a high enough temperature, the thin-film magnetic coating will either reach it’s Curie point or the platter itself will melt. That is safe and complete data destruction.

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