Register FAQ / Rules Forum Spy Search Today's Posts Mark Forums Read
Go Back   MacRumors Forums > Apple Systems and Services > Mac Basics and Help

Reply
 
Thread Tools Search this Thread Display Modes
Old Mar 21, 2010, 09:18 PM   #1
Luba
macrumors 6502
 
Join Date: Apr 2009
Put a magnet to a HDD or old floppy disk to "erase" them?

If I put a magnet to one of those old floppy disks or to a hard disk drive would that in effect be a secure erase?

But interesting I put a magnet on a hard disk drive platter and the magnet had no "pull" effect on it?? Perhaps the shiny silver color coating deflects the effect of magnetism??
Luba is offline   0 Reply With Quote
Old Mar 21, 2010, 09:21 PM   #2
GoCubsGo
macrumors Nehalem
 
GoCubsGo's Avatar
 
Join Date: Feb 2005
You'll need a very powerful magnet for it to actually matter.
Why not just erase via OS X or Windows?
GoCubsGo is offline   0 Reply With Quote
Old Mar 21, 2010, 09:22 PM   #3
-aggie-
macrumors Demi-God
 
-aggie-'s Avatar
 
Join Date: Jun 2009
Location: Where bunnies are welcome.
It would screw it up, but no, it would not be a secure erase. There are ways to get the parts you didn't magnetize off.
__________________
Google with site:macrumors.com as a parameter.
DFU Mode
-aggie- is offline   0 Reply With Quote
Old Mar 21, 2010, 09:22 PM   #4
GGJstudios
macrumors Westmere
 
Join Date: May 2008
Busting the Biggest PC Myths

Quote:
Magnets zap your data.
  • For venerable floppies, this statement holds true.
  • Fortunately, most modern storage devices, such as SD and CompactFlash memory cards, are immune to magnetic fields.
  • The same goes for hard drives. The only magnets powerful enough to scrub data from a drive platter are laboratory degaussers or those used by government agencies to wipe bits off media.
Want to erase data from a hard drive you plan to toss? Don't bother with a magnet. Overwrite the data that is stored on the media instead.

Last edited by GGJstudios; Mar 21, 2010 at 09:27 PM.
GGJstudios is offline   0 Reply With Quote
Old Mar 21, 2010, 09:22 PM   #5
CJS7070
macrumors 6502a
 
CJS7070's Avatar
 
Join Date: Dec 2008
Location: Chicago, IL
Keep in mind that hard drives are enclosed in faraday cages, so the magnet wouldn't have the full effect of an exposed platter... and that would destroy the drive right then and there.
CJS7070 is offline   0 Reply With Quote
Old Mar 21, 2010, 09:33 PM   #6
Luba
Thread Starter
macrumors 6502
 
Join Date: Apr 2009
I never saw a hard disk platter up close and personal, so a friend took it out. He drilled out the special screws in HDD case and took out the platter. Interestingly, inside the HDD case there was a strong magnet in there!

BTW, what is a faraday cage?

Quote:
Originally Posted by CJS7070 View Post
Keep in mind that hard drives are enclosed in faraday cages, so the magnet wouldn't have the full effect of an exposed platter... and that would destroy the drive right then and there.

Last edited by kainjow; Mar 21, 2010 at 09:54 PM. Reason: merged posts
Luba is offline   0 Reply With Quote
Old Mar 21, 2010, 09:37 PM   #7
GGJstudios
macrumors Westmere
 
Join Date: May 2008
Quote:
Originally Posted by Luba View Post
BTW, what is a faraday cage?
Google is your friend:
http://en.wikipedia.org/wiki/Faraday_cage
GGJstudios is offline   0 Reply With Quote
Old Mar 21, 2010, 11:11 PM   #8
Flynnstone
macrumors 65816
 
Flynnstone's Avatar
 
Join Date: Feb 2003
Location: Cold beer land
Quote:
Originally Posted by CJS7070 View Post
Keep in mind that hard drives are enclosed in faraday cages, so the magnet wouldn't have the full effect of an exposed platter... and that would destroy the drive right then and there.
Faraday Shields block electric fields NOT magnetic fields.

A strong magnetic will "disturb" a floppy, like 5 1/4"
A really strong magnetic will "disturb" a 3.5" floppy.
and even stronger for a hard drive.
I use disturb because its not necessarily erasing it.

Just erase it using OS X or ...
or use a secure erase tool.
or use a drill and hammer etc and physically destroy it.

Quote:
Originally Posted by Luba View Post
I never saw a hard disk platter up close and personal, so a friend took it out. He drilled out the special screws in HDD case and took out the platter. Interestingly, inside the HDD case there was a strong magnet in there!

BTW, what is a faraday cage?
I've got a couple I could post some pictures.

The strong magnetic is for the voice coil head actuator.
__________________
"You can't solve your problems with the same level of thinking that created the problems." - Einstein
New iMac 24"/G5 1.8/...

Last edited by kainjow; Mar 22, 2010 at 01:50 AM. Reason: merged posts
Flynnstone is offline   0 Reply With Quote

Reply
MacRumors Forums > Apple Systems and Services > Mac Basics and Help

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Similar Threads
thread Thread Starter Forum Replies Last Post
Disk Utility secure erase "7 pass secure erase" Appletise OS X Mavericks (10.9) 12 May 7, 2014 02:54 PM
Cannot erase HDD with mountain lion disk utility? error PavelT iMac 31 Apr 15, 2014 11:55 PM
Time machine "can't erase disk" woodslanding Windows, Linux & Others on the Mac 0 Dec 11, 2013 11:08 PM
"This Disk is Locked" on a new HDD? Fergie80 Mac Basics and Help 1 Nov 12, 2012 05:23 AM
How to erase Lacie HDD with magnet? NovemberWhiskey Mac Peripherals 6 Aug 15, 2012 12:00 PM

Forum Jump

All times are GMT -5. The time now is 04:54 AM.

Mac Rumors | Mac | iPhone | iPhone Game Reviews | iPhone Apps

Mobile Version | Fixed | Fluid | Fluid HD
Copyright 2002-2013, MacRumors.com, LLC