Cheap Bulk Eraser for Hard Disks?

cute-boy asks: "Recently I had to replace some hard disk drives from the same batch which had failed, while still under warranty. Because the drives were no longer recognized by the SCSI controller, it was not possible to erase the data on them. In view of the sensitivity of the data contained upon them, and the chance this was still forensically recoverable, our company decided to buy new drives rather than risk the disclosure of their contents by returning then to the supplier. How would you non-destructively (physically) destroy data on a hard disk without access to a bulk eraser? Obviously in this case it's a bit late to be thinking of using encryption."

Re:Why no physical?

[linkedlinked]

I think the idea was that the poster would like to preserve the drives, and thus still qualify for possible returns (warranty or otherwise). The options are "Physically destroy (or retain ownership of)" and "secure wipe, return for $$$." Clearly, one is a more attractive solution, especially if the volume of disks in question is particularly large.

Introduction to slashdot groupthink...

[IANAAC]

Highly recognizable keyword(s) + question mark = highly qualified answers from first posters who never made it past the first sentence.

It's because they don't know the answer

[Travoltus]

to the pertinent question.

There is probably no such thing as a cheap and effective bulk eraser. We have an agreement with Maxtor (now Seagate) that allows us to send in the chassis for a replacement, minus the platters. The replacement contract is expensive, though, but we need it since we have a LOT of banking data.

Re:Physically destroy the platters

[mrbcs]

And while yer at it, pull out thoses monster magnets inside! They're lots of fun! Especially the ones from those old quantum bigfoots. It's damn near impossible pulling them off a piece of steel. Great for magnetizing screw drivers.

Re:Why no physical?

[Wwolmack]

Breaking hard drive platters is not easy, and given a significant level of paranoia, physically snapping the platters in half may not be enough.
Degaussing the drives may not be thorough enough, given various anecdotes about the ability to recover data off almost any drive using fancy super-expensive equipment.

Unless you've got IBM Deathstar 75GXP's (and if you do, well your data is already as good as gone), your platters are probably metal. Even if you have Deathstars, their platters are glass and are susceptible to the method below:

Metal melts. Magnetic metals lose their net magnetism below the melting point [wikipedia.org]. So find somebody with a kiln, and turn the platters into inert blobs.

You are stuck with these drives. You can't return them for replacement, and if you keep them and still get a replacement, the data is still on the platters. You could just send them to a data-destruction company, but where's the fun in that?