the magnets inside a hard drive are dangerously strong

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YOyoYOhowsDAjello

Moderator<br>A/V & Home Theater<br>Elite member
Aug 6, 2001
31,204
45
91
Originally posted by: Modelworks
yep, they are very strong.
Not as strong as ones you can buy, like the 35lb variety. meaning it takes 35lbs of force to pull them apart.

If the magnet was oriented towards the platter it would wreck havoc on the data.
Instead it makes the actuator function, that moves the arm back and forth, and also serves as an auto head parking mechanism.


Fun thing to do with these I did last week.
Take a eraser, the big ones that are kind of flat.
Hollow it out enough to pllace the magnet in the bottom.
Glue it in place.

Two things you can do now.
Attach it to metal objects and watch as peopled try to pick it up.

Or my favorite.
Amaze the kids.
Place the eraser on a table top and place the other magnet below the table surface.
Use your 'mind power' to make the eraser move :)


Oh, and make sure you keep it far away from your wallet.
It can corrupt credit cards in a single pass.

35 pounds? pffft :p

http://www.unitednuclear.com/magnetfull7.jpg (800 pounds)
http://www.unitednuclear.com/magnets.htm
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Originally posted by: BlahBlahYouToo
Originally posted by: Superself
can you elaborate on the "dangerously strong" remark?

given its small size, you would never expect it to have such a strong magnetic pull.
put it near any metal objects and it will pull it towards the magnet at a high rate of speed.
put the 2 magnets together (comes in 2s) and it would be a struggle to pull them apart, possibly injuring yourself in the process.

No offense, but you have to be a serious moron to get hurt by a hard drive magnet. Unless you stuck them on your balls or something...but that brings us right back to "serious moron".

Yeah, they are surprisingly strong. But not dangerously so.
 

Baked

Lifer
Dec 28, 2004
36,052
17
81
I have a couple of them from a failed HD I took apart. Handle with caution.
 

Modelworks

Lifer
Feb 22, 2007
16,240
7
76
Originally posted by: BlahBlahYouToo
Originally posted by: Modelworks


Oh, and make sure you keep it far away from your wallet.
It can corrupt credit cards in a single pass.

oh crap, it was kinda on my thigh near my wallet when i was messing around with it.
didn't even think about it.


uhoh :)
 

middlehead

Diamond Member
Jul 11, 2004
4,573
2
81
Originally posted by: BlahBlahYouToo
oh crap, it was kinda on my thigh near my wallet when i was messing around with it.
didn't even think about it.
I hope you weren't planning to have children.
 

Analog

Lifer
Jan 7, 2002
12,755
3
0
Originally posted by: BlahBlahYouToo
seriously, i had no idea.
if u need a strong magnet and have a dead hard drive laying around, take it apart.

Check out the massive magnet I took out of my '82 vintage 10 Megabyte (yes megabyte) Hard drive:

Text

BEAT THAT!
 

slag

Lifer
Dec 14, 2000
10,473
81
101
Originally posted by: BlahBlahYouToo
Originally posted by: Superself
can you elaborate on the "dangerously strong" remark?

given its small size, you would never expect it to have such a strong magnetic pull.
put it near any metal objects and it will pull it towards the magnet at a high rate of speed.
put the 2 magnets together (comes in 2s) and it would be a struggle to pull them apart, possibly injuring yourself in the process.

Sure you would.. they are rare earth magnets.

This is all pretty much common knowledge to most people.
 

Fritzo

Lifer
Jan 3, 2001
41,920
2,161
126
How to kill yourself using two of those magnets:

Step 1: Swallow one.
Step 2: Wait about 10 minutes, then swallow the second one

The two magnets will eventually attract themselves together through the walls of the small intestine, causing necrosis, and eventually death.

Get to it and post your progress!
 
S

SlitheryDee

Upon reading this thread I disassembled an old HD...and immediately pinched the shit out of my left index finger with the magnets inside it. Still hurts like hell. :(


Edit: Ugh It's turning purple.
 

Throckmorton

Lifer
Aug 23, 2007
16,829
3
0
Originally posted by: slag
Originally posted by: BlahBlahYouToo
Originally posted by: Superself
can you elaborate on the "dangerously strong" remark?

given its small size, you would never expect it to have such a strong magnetic pull.
put it near any metal objects and it will pull it towards the magnet at a high rate of speed.
put the 2 magnets together (comes in 2s) and it would be a struggle to pull them apart, possibly injuring yourself in the process.

Sure you would.. they are rare earth magnets.

This is all pretty much common knowledge to most people.

Are you sure they are rare earth magnets? I thought they were made by magnetizing molten steel, and then cooling it with all the molecules in the aligned position.


I discovered the other day that they are horseshoe magnets. Both the N and S are on the same side. You can feel that if you take a small, normal magnet, and move it back and forth in front of the HD magnet.
That's why the back, where they attach to the metal backing, is not magnetic.
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
Originally posted by: YOyoYOhowsDAjello
35 pounds? pffft :p

http://www.unitednuclear.com/magnetfull7.jpg (800 pounds)
http://www.unitednuclear.com/magnets.htm

Yep, the warnings that go along with those magnets aren't to be taken too lightly. Before entering a room, make sure you've carefully planned out the route you're going to take if you're carrying one of those magnets. Don't walk near scissors or other sharp metal objects! Put one of those magnets in each hand if and only if you're bored of having fingers.
 
Jul 10, 2007
12,041
3
0
Originally posted by: jagec
Originally posted by: BlahBlahYouToo
Originally posted by: Superself
can you elaborate on the "dangerously strong" remark?

given its small size, you would never expect it to have such a strong magnetic pull.
put it near any metal objects and it will pull it towards the magnet at a high rate of speed.
put the 2 magnets together (comes in 2s) and it would be a struggle to pull them apart, possibly injuring yourself in the process.

No offense, but you have to be a serious moron to get hurt by a hard drive magnet. Unless you stuck them on your balls or something...but that brings us right back to "serious moron".

Yeah, they are surprisingly strong. But not dangerously so.

trying to pry the 2 magnets together. they clamp down on your fingers and pinch some skin.
you're hurt.
:roll:
 

Kelemvor

Lifer
May 23, 2002
16,928
8
81
I have a few of them I took apart just to get the magnets. They are freaky strong.
 

Iron Woode

Elite Member
Super Moderator
Oct 10, 1999
31,169
12,700
136
Originally posted by: Superself
can you elaborate on the "dangerously strong" remark?
if you get enough of them you can be a real life Magneto.
 

Eeezee

Diamond Member
Jul 23, 2005
9,922
0
76
Originally posted by: BlahBlahYouToo
Originally posted by: Superself
can you elaborate on the "dangerously strong" remark?

given its small size, you would never expect it to have such a strong magnetic pull.
put it near any metal objects and it will pull it towards the magnet at a high rate of speed.
put the 2 magnets together (comes in 2s) and it would be a struggle to pull them apart, possibly injuring yourself in the process.

If you're dumb enough to pull at something until you HURT YOURSELF then you are a moron.

There's nothing dangerous about the magnet inside a hard drive. Yes, it's strong. Hurting yourself by pulling apart two strong magnets is equivalent to hurting yourself while trying to pull apart a Victorian era dining table without tools.
 

Eeezee

Diamond Member
Jul 23, 2005
9,922
0
76
Originally posted by: Modelworks
yep, they are very strong.
Not as strong as ones you can buy, like the 35lb variety. meaning it takes 35lbs of force to pull them apart.

If the magnet was oriented towards the platter it would wreck havoc on the data.
Instead it makes the actuator function, that moves the arm back and forth, and also serves as an auto head parking mechanism.


Fun thing to do with these I did last week.
Take a eraser, the big ones that are kind of flat.
Hollow it out enough to pllace the magnet in the bottom.
Glue it in place.

Two things you can do now.
Attach it to metal objects and watch as peopled try to pick it up.

Or my favorite.
Amaze the kids.
Place the eraser on a table top and place the other magnet below the table surface.
Use your 'mind power' to make the eraser move :)


Oh, and make sure you keep it far away from your wallet.
It can corrupt credit cards in a single pass.

That last line, I believe, is a myth. It might wipe the data if they come in contact, but I don't think passing the magnet over your wallet will do anything to the credit cards (it's a strong magnet, but not that strong)
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
Originally posted by: Eeezee
Originally posted by: Modelworks
yep, they are very strong.
Not as strong as ones you can buy, like the 35lb variety. meaning it takes 35lbs of force to pull them apart.

If the magnet was oriented towards the platter it would wreck havoc on the data.
Instead it makes the actuator function, that moves the arm back and forth, and also serves as an auto head parking mechanism.


Fun thing to do with these I did last week.
Take a eraser, the big ones that are kind of flat.
Hollow it out enough to pllace the magnet in the bottom.
Glue it in place.

Two things you can do now.
Attach it to metal objects and watch as peopled try to pick it up.

Or my favorite.
Amaze the kids.
Place the eraser on a table top and place the other magnet below the table surface.
Use your 'mind power' to make the eraser move :)


Oh, and make sure you keep it far away from your wallet.
It can corrupt credit cards in a single pass.

That last line, I believe, is a myth. It might wipe the data if they come in contact, but I don't think passing the magnet over your wallet will do anything to the credit cards (it's a strong magnet, but not that strong)

I use fairly strong neodymium magnets in physics class. When I'm done with a demo, I have this bad habit of putting the smaller things in my pocket so I don't misplace them. I've ruined every credit and debit card I've had.
 

Modelworks

Lifer
Feb 22, 2007
16,240
7
76
Originally posted by: DrPizza
Originally posted by: Eeezee
Originally posted by: Modelworks


Oh, and make sure you keep it far away from your wallet.
It can corrupt credit cards in a single pass.

That last line, I believe, is a myth. It might wipe the data if they come in contact, but I don't think passing the magnet over your wallet will do anything to the credit cards (it's a strong magnet, but not that strong)

I use fairly strong neodymium magnets in physics class. When I'm done with a demo, I have this bad habit of putting the smaller things in my pocket so I don't misplace them. I've ruined every credit and debit card I've had.


I did that to checks.
Checks in case people didn't know are now printed with magnetic ink.
External magnets can screw it up so bad that magnetic readers can't read the check, making processing time longer.
 

Modelworks

Lifer
Feb 22, 2007
16,240
7
76
Originally posted by: Eeezee
Originally posted by: Modelworks

Oh, and make sure you keep it far away from your wallet.
It can corrupt credit cards in a single pass.

That last line, I believe, is a myth. It might wipe the data if they come in contact, but I don't think passing the magnet over your wallet will do anything to the credit cards (it's a strong magnet, but not that strong)

Its no myth.
Have you seen the degaussing pads that stores use to clear the security tags ?
Notice they have a warning not to place credit cards on them ?
Those are about 5 times weaker than the magnets we are talking about.
 

GTaudiophile

Lifer
Oct 24, 2000
29,767
33
81
Any know how to uncrew the scews on a HDD. None of my tools are small enough/right type to get at them.
 

sdifox

No Lifer
Sep 30, 2005
98,851
17,321
126
Originally posted by: GTaudiophile
Any know how to uncrew the scews on a HDD. None of my tools are small enough/right type to get at them.

why bother with the screws? not like you are going to put it back together and boot off it.
 

40Hands

Diamond Member
Jun 29, 2004
5,042
0
71
"A small child recently lost his hand when his father left two # 31 supermagnets unattended. The child picked one up and when he approached the other magnet on a nearby table, it became airborne and obliterated his small hand."

:Q
 

GTaudiophile

Lifer
Oct 24, 2000
29,767
33
81
Originally posted by: sdifox
Originally posted by: GTaudiophile
Any know how to uncrew the scews on a HDD. None of my tools are small enough/right type to get at them.

why bother with the screws? not like you are going to put it back together and boot off it.

You mean pry it open then?