I doubt that is going to work unless you pull the platter out of the case, and if you do, just wipe it with sandpaper.:-)  It is an interesting problem in theory, but in practice I doubt that Dell is going to try to recover the data.  You might see if your local computer geek can try SpinRight on it - that might see it and let you do a low level format.

A magnet on the back of a speaker will do nicely. Or you could go to an auto salvage yard and ask  them to swing their electro magnet crane over it a couple of times. That should do it. Just don't be holding it when they swing the magnet over it. He might miss!!    

We recently "retired" a couple hard drives. The "retirement" involved a total dis-assembly of both hard drives down to the platters. On one drive the platters were made of glass. A simple smack with a hammer demolished those. The other drive platter was made of metal. I took great joy in venting my internal agressions upon this metal platter with various tools. After that it too was useless. Twas a fun day at Ramblin Lamb Photogaphy!!

I had my C drive fail about a week ago, and though I'm back up to speed with a new HD and apps reinstalled and External HD having saved the day for data backup, I have to return the old HD to Dell or otherwise pay for the new one.

Dell sent a repair guy out to replace and install the new one and got me started on reinstalling Windows.

Before I return the old HD, I want to secure my privacy by wiping the old data off of it. He suggested doing it with a magnet, but I should've asked him where is the best place to buy one. One powerful enough to do the job.

Anyone gone through this? Would any old horsehoe shaped,  elementary school science kit magnet get it done, or do I need something stronger?

I went ahead and bought some pretty good magnets at Lowes and scooted them around the top & bottom surfaces of the HD. When I moved the ones on top, the magnets on bottom responded likewise. I also dropped the HD a few times and drilled a few holes in it. All in all, I figure any remaining data that may have survived the first failure did not survive my intentional abuse.  

Marshal,

The only certain way to protect the files is to take a hammer to the hard disk.

Regards,