I just had to post this. While ago the original hard drive went out in
my pc. I replaced it & all went well, and since I'd never looked inside
one of these, I took it apart. The beautiful, nearly "industrial art
sculpture" of the mirror platter assembly/aluminum motor, casting, all
held with cool fasteners was impressive enough, but then I started
playing with the magnets from the pickup assembly. My god, they're
strong! Neodymium, I think. So strong that I actually gave myself a
small blood blister when the 2 snapped together as I played with them.
About this same time, the door catch broke on my faithful 20 year old
clothes dryer. Not a chance of getting a replacement catch, so for the
past 2 weeks I've been propping the unused base from my drill press
against the door to hold it shut. Then it dawned on me: "I bet those
magnets from the HDD are more than strong enough to hold this thing shut
against the seal & force of the door switch". Works like a charm, in
fact I only need ONE of them! Judging from the pull now required to
open the door, it's actually tighter than it was with the original
catch! Further justification for my "never throw ANYTHING out" policy ;-)

Dan

On Mon, 02 May 2005 20:39:31 -0400, Dan
wrote:

:I just had to post this. While ago the original hard drive went out in
:my pc. I replaced it & all went well, and since I'd never looked inside
ne of these, I took it apart. The beautiful, nearly "industrial art
:sculpture" of the mirror platter assembly/aluminum motor, casting, all
:held with cool fasteners was impressive enough, but then I started
laying with the magnets from the pickup assembly. My god, they're
:strong! Neodymium, I think. So strong that I actually gave myself a
:small blood blister when the 2 snapped together as I played with them.
:About this same time, the door catch broke on my faithful 20 year old
:clothes dryer. Not a chance of getting a replacement catch, so for the
ast 2 weeks I've been propping the unused base from my drill press
:against the door to hold it shut. Then it dawned on me: "I bet those
:magnets from the HDD are more than strong enough to hold this thing shut
:against the seal & force of the door switch". Works like a charm, in
:fact I only need ONE of them! Judging from the pull now required to
pen the door, it's actually tighter than it was with the original
:catch! Further justification for my "never throw ANYTHING out" policy ;-)
:
an

The only reason my stove's oven shuts reasonably tight is that I screwed
a large ring magnet at the top between the stove and the hinged door.
Did this probably around 10 years ago - works great.

I took apart my oldest HD around 6 months ago, a 220 MB Maxtor. Pretty
things in there, but be careful with those shiny disks. I'm informed
that some of them are made of glass, not the metal you might suppose and
some people have been cut badly playing with them. In my case, I think
they ARE metal, and they are not only very pretty, they make a very nice
sound when they clang against each other. They'd make a very nice
mobile, is my thinking, when I get around to it.

I have several other retired HDDs, and plan to similarly pillage them.
The magnets are indeed powerful, and what I did was saw them in half
with a hacksaw and glue them to wooden "handles" with 5 minute epoxy.
They are hard to deal with if you don't do something like that. As such,
they make fantastic refrigerator magnets. If you have a Sonicare
toothbrush, BTW, don't just throw out the brushes (you are supposed to
change them every 6 months). You will notice two tiny magnets on the end
of those brushes, and they come right off if you pull on them with a
pliers. They are extremely powerful, and glued to a small piece of wood,
they make fantastic refrigerator magnets.

Dan (as well!)

BTW, I do not subscribe to the policy of never throwing anything away.
If it's potentially (there's the value judgement) useful, keep it. If
not, you really better get rid of it.

On Mon, 02 May 2005 20:39:31 -0400, Dan
wrote:

I started
playing with the magnets from the pickup assembly. My god, they're
strong! Neodymium, I think. So strong that I actually gave myself a
small blood blister when the 2 snapped together as I played with them.

That's a good tip. I never thought of the magnets when I took apart
the drives. Now that I want them I don't have dead drives anymore.

Do look up http://groups.yahoo.com/group/lrk-torquemax/ on making your
own brushless motors. That's what I want super magnets for.

Dan writes:

I just had to post this. While ago the original hard drive went out
in my pc. I replaced it & all went well, and since I'd never looked
inside one of these, I took it apart. The beautiful, nearly
"industrial art sculpture" of the mirror platter assembly/aluminum
motor, casting, all held with cool fasteners was impressive enough,
but then I started playing with the magnets from the pickup assembly.
My god, they're strong! Neodymium, I think. So strong that I
actually gave myself a small blood blister when the 2 snapped together
as I played with them. About this same time, the door catch broke on
my faithful 20 year old clothes dryer. Not a chance of getting a
replacement catch, so for the past 2 weeks I've been propping the
unused base from my drill press against the door to hold it shut.
Then it dawned on me: "I bet those magnets from the HDD are more than
strong enough to hold this thing shut against the seal & force of the
door switch". Works like a charm, in fact I only need ONE of them!
Judging from the pull now required to open the door, it's actually
tighter than it was with the original catch! Further justification
for my "never throw ANYTHING out" policy ;-)

If you think those are impressive, you should see the magnets on early
'90s 5-1/4" full height high performance disk drives! (Or even earlier
8" drives.) Sometime before that, they didn't have neodymium rare earth
magnets, so not as impressive.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

"PaPaPeng" wrote in message
...
On Mon, 02 May 2005 20:39:31 -0400, Dan
wrote:

I started
playing with the magnets from the pickup assembly. My god, they're
strong! Neodymium, I think. So strong that I actually gave myself a
small blood blister when the 2 snapped together as I played with them.

That's a good tip. I never thought of the magnets when I took apart
the drives. Now that I want them I don't have dead drives anymore.


I always pull the magnets from dead hard drives, those from ancient 5.25"
SCSI server/AV drives are particularly potent, be careful!

Dan wrote:
I just had to post this. While ago the original hard drive went out in
my pc. I replaced it & all went well, and since I'd never looked inside
one of these, I took it apart. The beautiful, nearly "industrial art
sculpture" of the mirror platter assembly/aluminum motor, casting, all
held with cool fasteners was impressive enough, but then I started
playing with the magnets from the pickup assembly. My god, they're
strong! Neodymium, I think. So strong that I actually gave myself a
small blood blister when the 2 snapped together as I played with them.
About this same time, the door catch broke on my faithful 20 year old
clothes dryer. Not a chance of getting a replacement catch, so for the
past 2 weeks I've been propping the unused base from my drill press
against the door to hold it shut. Then it dawned on me: "I bet those
magnets from the HDD are more than strong enough to hold this thing shut
against the seal & force of the door switch". Works like a charm, in
fact I only need ONE of them! Judging from the pull now required to
open the door, it's actually tighter than it was with the original
catch! Further justification for my "never throw ANYTHING out" policy ;-)

Dan

A couple of years ago I built a diamagnetic levitation demonstrator
using of those high strength magnets and some bismuth I bought on eBay.

I just HAD to try it to see it work. Seeing is believing!

http://home.comcast.net/%7Ejwisnia18/jeff/diamag.html

Jeff
--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"As long as there are final exams, there will be prayer in public
schools"

On Mon, 02 May 2005 20:39:31 -0400, Dan
wrote:

I just had to post this. While ago the original hard drive went out in

snip

catch! Further justification for my "never throw ANYTHING out" policy ;-)



Ahah, me too. My barn is full of good treasures. The magnets off
ex-Microwave magnetrons are also pretty good, not that powerful, but
they are large. Ideal for many things around the workshop, holding
things while welding, holding the chuck key on the side of the
drill-press, etc ,etc.

One of the best things to strip down are old photocopiers, motors,
switches, LV and HV PSUs, LEDs, gears, lamps and lots of other stuff.

The stupid EU does not need their WEEE directive, I'm doing my best !!


Barry Lennox

"Dan" wrote in message
...
I just had to post this. While ago the original hard drive went out in
my pc. I replaced it & all went well, and since I'd never looked inside
one of these, I took it apart. The beautiful, nearly "industrial art
sculpture" of the mirror platter assembly/aluminum motor, casting, all
held with cool fasteners was impressive enough, but then I started
playing with the magnets from the pickup assembly. My god, they're
strong! Neodymium, I think. So strong that I actually gave myself a
small blood blister when the 2 snapped together as I played with them.
About this same time, the door catch broke on my faithful 20 year old
clothes dryer. Not a chance of getting a replacement catch, so for the
past 2 weeks I've been propping the unused base from my drill press
against the door to hold it shut. Then it dawned on me: "I bet those
magnets from the HDD are more than strong enough to hold this thing shut
against the seal & force of the door switch". Works like a charm, in
fact I only need ONE of them! Judging from the pull now required to
open the door, it's actually tighter than it was with the original
catch! Further justification for my "never throw ANYTHING out" policy ;-)

Dan

A near neighbour managed to drop his car keys down a drain in the street
just as he was to drive to an airport. I tied an ex-5 1/4 magnet to a piece
of string vertically and he went fishing. It came up with his keys on first
attempt.

Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse

On 02 May 2005 23:07:44 -0400, Sam Goldwasser
put finger to keyboard and composed:

Dan writes:

I just had to post this. While ago the original hard drive went out
in my pc. I replaced it & all went well, and since I'd never looked
inside one of these, I took it apart. The beautiful, nearly
"industrial art sculpture" of the mirror platter assembly/aluminum
motor, casting, all held with cool fasteners was impressive enough,
but then I started playing with the magnets from the pickup assembly.
My god, they're strong! Neodymium, I think. So strong that I
actually gave myself a small blood blister when the 2 snapped together
as I played with them. About this same time, the door catch broke on
my faithful 20 year old clothes dryer. Not a chance of getting a
replacement catch, so for the past 2 weeks I've been propping the
unused base from my drill press against the door to hold it shut.
Then it dawned on me: "I bet those magnets from the HDD are more than
strong enough to hold this thing shut against the seal & force of the
door switch". Works like a charm, in fact I only need ONE of them!
Judging from the pull now required to open the door, it's actually
tighter than it was with the original catch! Further justification
for my "never throw ANYTHING out" policy ;-)

If you think those are impressive, you should see the magnets on early
'90s 5-1/4" full height high performance disk drives! (Or even earlier
8" drives.) Sometime before that, they didn't have neodymium rare earth
magnets, so not as impressive.

The voice coil magnet in the Control Data drives of the early 80s was
about 15 x 15 x 15 cm. It was a back breaker. I still have one
somewhere.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.

Another good source of powerful magnets is the field
magnets from some motors. I believe that they are
becoming common in automobile starters.

Gideon

Franc Zabkar wrote
The voice coil magnet in the Control Data drives of the early 80s was
about 15 x 15 x 15 cm. It was a back breaker. I still have one
somewhere.

==============

Those magnets were 6" x 6" x 6" ? Impressive.

["Followup-To:" header set to sci.electronics.repair.]
On Tue, 03 May 2005 18:04:05 GMT, Gideon wrote:

Franc Zabkar wrote
The voice coil magnet in the Control Data drives of the early 80s was
about 15 x 15 x 15 cm. It was a back breaker. I still have one
somewhere.

==============

Those magnets were 6" x 6" x 6" ? Impressive.

Yep. Easily. I have the voice coil magnets off an old, "small"
DEC 5MB disk drive from the mid-70's.
They are 5x5x2" ( 13x13x6 cm approx.)

Serious magnets, those.

Jonesy
--
| Marvin L Jones | jonz | W3DHJ | linux
| Gunnison, Colorado | @ | Jonesy | OS/2 __
| 7,703' -- 2,345m | config.com | DM68mn SK

In article , Dan wrote:
I just had to post this.

The last time I replaced a disk drive, I couldn't find a means of opening
it to grab the magnets. It wasn't Torx, security Torx, allen, or anything
else I had in my reasonably well-equipped set of wrenches. Finally conceded
defeat and discarded it.

Did I have an oddball (don't remember the brand) or was it simply a matter of
me being an idiot and not having a common tool?

Art

Dan wrote:
Then it dawned on me: "I bet those magnets from the HDD are
more than strong enough to hold this thing shut against the seal &
force of the door switch". Works like a charm, in fact I only need
ONE of them! Judging from the pull now required to
open the door, it's actually tighter than it was with the original
catch! Further justification for my "never throw ANYTHING out"
policy ;-)

Yeah, they're pretty amazing. I sometimes carry a pair around in to play
with. Don't get them anywhere near magnetic media, of course, and don't let
small children handle them unless they're firmly stuck together. I've seen
people injure themselves, as well....

jak

Dan

James Sweet wrote:
"PaPaPeng" wrote in message
...
On Mon, 02 May 2005 20:39:31 -0400, Dan
wrote:

I started
playing with the magnets from the pickup assembly. My god, they're
strong! Neodymium, I think. So strong that I actually gave myself
a small blood blister when the 2 snapped together as I played with
them.

That's a good tip. I never thought of the magnets when I took apart
the drives. Now that I want them I don't have dead drives anymore.


I always pull the magnets from dead hard drives, those from ancient
5.25" SCSI server/AV drives are particularly potent, be careful!

I've got several of those awaiting the screwdriver....g

jak

Dan_Musicant wrote:
On Mon, 02 May 2005 20:39:31 -0400, Dan
wrote:

I just had to post this. While ago the original hard drive went out
in my pc. I replaced it & all went well, and since I'd never looked
inside one of these, I took it apart. The beautiful, nearly
"industrial art sculpture" of the mirror platter assembly/aluminum
motor, casting, all held with cool fasteners was impressive enough,
but then I started playing with the magnets from the pickup
assembly. My god, they're strong! Neodymium, I think. So strong
that I actually gave myself a small blood blister when the 2 snapped
together as I played with them. About this same time, the door catch
broke on my faithful 20 year old clothes dryer. Not a chance of
getting a replacement catch, so for the past 2 weeks I've been
propping the unused base from my drill press against the door to
hold it shut. Then it dawned on me: "I bet those magnets from the
HDD are more than strong enough to hold this thing shut against the
seal & force of the door switch". Works like a charm, in fact I
only need ONE of them! Judging from the pull now required to
open the door, it's actually tighter than it was with the original
catch! Further justification for my "never throw ANYTHING out"
policy ;-)

Dan

The only reason my stove's oven shuts reasonably tight is that I
screwed a large ring magnet at the top between the stove and the
hinged door. Did this probably around 10 years ago - works great.

I took apart my oldest HD around 6 months ago, a 220 MB Maxtor. Pretty
things in there, but be careful with those shiny disks. I'm informed
that some of them are made of glass, not the metal you might suppose
and some people have been cut badly playing with them. In my case, I
think they ARE metal, and they are not only very pretty, they make a
very nice sound when they clang against each other. They'd make a
very nice mobile, is my thinking, when I get around to it.

Wind Chimes...I'm collecting a several platters in different sizes: 5 1/4",
3 1/2", (whatever" size they use in laptops). I've been surprised to find
that despite the age/capacity of the original (3 1/2") drive, the platters
themselves appear almost physically identical...they even sound the same
note when struck. I'm trying to decide: which piece of a drive would make
an artistically aesthetic 'clapper' for the piece? So far I'm leaning
toward the actual head assembly from one unit. Once I pull the others
apart, I might find something more attractive. Of course, I could use one
of the smaller platters, as well. Also, I need to choose an appropriate
piece to suspend the chimes from...shell from one of the 5 1/4" full-height
units?

I have several other retired HDDs, and plan to similarly pillage them.
The magnets are indeed powerful, and what I did was saw them in half
with a hacksaw and glue them to wooden "handles" with 5 minute epoxy.
They are hard to deal with if you don't do something like that. As
such, they make fantastic refrigerator magnets. If you have a Sonicare
toothbrush, BTW, don't just throw out the brushes (you are supposed to
change them every 6 months). You will notice two tiny magnets on the
end of those brushes, and they come right off if you pull on them
with a pliers. They are extremely powerful, and glued to a small
piece of wood, they make fantastic refrigerator magnets.

Dan (as well!)

BTW, I do not subscribe to the policy of never throwing anything away.
If it's potentially (there's the value judgement) useful, keep it. If
not, you really better get rid of it.

Yeah, but how to decide if something will ever be 'useful'...(regretting
those H.H. Scott tube receivers I discarded in the 70's).

jak

(Arthur Shapiro) writes:

In article , Dan wrote:
I just had to post this.

The last time I replaced a disk drive, I couldn't find a means of opening
it to grab the magnets. It wasn't Torx, security Torx, allen, or anything
else I had in my reasonably well-equipped set of wrenches. Finally conceded
defeat and discarded it.

Did I have an oddball (don't remember the brand) or was it simply a matter of
me being an idiot and not having a common tool?

You'd have to describe the screw heads or whatever. I've yet to come up
against a dead harddrive I couldn't get open reasonably non-destructively.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

Allodoxaphobia ) writes:
["Followup-To:" header set to sci.electronics.repair.]
On Tue, 03 May 2005 18:04:05 GMT, Gideon wrote:

Franc Zabkar wrote
The voice coil magnet in the Control Data drives of the early 80s was
about 15 x 15 x 15 cm. It was a back breaker. I still have one
somewhere.

==============

Those magnets were 6" x 6" x 6" ? Impressive.

Yep. Easily. I have the voice coil magnets off an old, "small"
DEC 5MB disk drive from the mid-70's.
They are 5x5x2" ( 13x13x6 cm approx.)

Serious magnets, those.

But don't forget the punchline, that the hard drives were massive
back then.


Michael

Arthur Shapiro ) writes:
In article , Dan wrote:
I just had to post this.

The last time I replaced a disk drive, I couldn't find a means of opening
it to grab the magnets. It wasn't Torx, security Torx, allen, or anything
else I had in my reasonably well-equipped set of wrenches. Finally conceded
defeat and discarded it.

Did I have an oddball (don't remember the brand) or was it simply a matter of
me being an idiot and not having a common tool?

Art

I've come across that, though I don't know whether they are odd or
just sized I don't have.

If you're just scrapping the drives, drill out the screws.

Another thing I've found useful, if the heads aren't recessed, is
to use a cutting wheel on my "Dremel tool" to put a slot on it
so I can use a regular screwdriver.

Michael

"Arthur Shapiro" wrote in message
...
In article , Dan
wrote:
I just had to post this.

The last time I replaced a disk drive, I couldn't find a means of opening
it to grab the magnets. It wasn't Torx, security Torx, allen, or anything
else I had in my reasonably well-equipped set of wrenches. Finally
conceded
defeat and discarded it.

Did I have an oddball (don't remember the brand) or was it simply a matter
of
me being an idiot and not having a common tool?



A lot of them are metric torx.

In article ,
"Gideon" wrote:

Another good source of powerful magnets is the field
magnets from some motors. I believe that they are
becoming common in automobile starters.

I've never seen one that was anywhere near as strong as a hard drive
magnet.

Isaac

In article ,
"jakdedert" wrote:

Dan wrote:
Then it dawned on me: "I bet those magnets from the HDD are
more than strong enough to hold this thing shut against the seal &
force of the door switch". Works like a charm, in fact I only need
ONE of them! Judging from the pull now required to
open the door, it's actually tighter than it was with the original
catch! Further justification for my "never throw ANYTHING out"
policy ;-)

Yeah, they're pretty amazing. I sometimes carry a pair around in to play
with. Don't get them anywhere near magnetic media, of course, and don't let
small children handle them unless they're firmly stuck together. I've seen
people injure themselves, as well....

Be careful with those. They're very brittle, and can shatter when they
snap together. You might think that the magnetic field would control the
shards, but it doesn't.

When the magnets crash together and shatter, the strength goes way down,
and the shards come out *really fast*.

Isaac

I once used a motor from an old dryer to fix a hard drive.

No, Really!

On Wed, 04 May 2005 03:28:28 GMT, "James Sweet"
wrote:

Did I have an oddball (don't remember the brand) or was it simply a matter
of me being an idiot and not having a common tool?



A lot of them are metric torx.

Is there such a thing as a SAE vs metric torx? I see only a tool ID
number but no dimensions specified.

One item one should check though is if there is a centre pin in the
screw fastener's recess. If so it will require a driver tool bit with
a hole in the center to accept this pin. I think the tools are
described as security bit sets. When these security fasteners first
came out there were no tools available but I was able to get around it
by drilling the hole with a dental burr (drill bit) in the torx
driver.

"Matt" wrote in message
oups.com...
I once used a motor from an old dryer to fix a hard drive.

No, Really!


One of those huge cabinet drives that held about 5mb and had a good sized
induction motor driving the spindle?

On Wed, 04 May 2005 04:33:00 GMT, "James Sweet"
wrote:


"Matt" wrote in message
roups.com...
I once used a motor from an old dryer to fix a hard drive.

No, Really!


One of those huge cabinet drives that held about 5mb and had a good sized
induction motor driving the spindle?

My memory is fading since I last serviced those 20MB HDs some 20 years
ago. They weighed at least 100 lbs and took two guys to lift it
because there's no way to put one's arms around one to do any lifting.
It would also have hurt many backbones. The drive's mass was a
design decision to provide inertia to dampen out any outside
vibrations such as someone slamming a door or a heavy guy walking
nearby. Plus that voice coil's seek operations shook the whole drive
like a rat caught by a terrier. The RW head was the size of a stick
of gum and it provided us service guys a good paying job because they
crashed often enough for the computer customer to pay big bucks to be
on a service contract. I think the platters were 14 inch diameter
and when the RW head touched the surface it gouged out a deep groove
into the aluminium.

On 3 May 2005 23:39:22 GMT, (Michael Black)
put finger to keyboard and composed:


Allodoxaphobia ) writes:
["Followup-To:" header set to sci.electronics.repair.]
On Tue, 03 May 2005 18:04:05 GMT, Gideon wrote:

Franc Zabkar wrote
The voice coil magnet in the Control Data drives of the early 80s was
about 15 x 15 x 15 cm. It was a back breaker. I still have one
somewhere.

==============

Those magnets were 6" x 6" x 6" ? Impressive.

Yep. Easily. I have the voice coil magnets off an old, "small"
DEC 5MB disk drive from the mid-70's.
They are 5x5x2" ( 13x13x6 cm approx.)

Serious magnets, those.

But don't forget the punchline, that the hard drives were massive
back then.

The 300MB drives weighed ~600lb. Years ago a scrap dealer paid me ~$70
for the aluminium deck, and I'm now using the frame as a tool trolley.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.

Arthur Shapiro wrote:
In article , Dan
wrote:
I just had to post this.

The last time I replaced a disk drive, I couldn't find a means of
opening
it to grab the magnets. It wasn't Torx, security Torx, allen, or
anything
else I had in my reasonably well-equipped set of wrenches. Finally
conceded
defeat and discarded it.

Did I have an oddball (don't remember the brand) or was it simply a
matter of
me being an idiot and not having a common tool?

Art


I had the same problem. Just use some wire cutters to get the screws
broken loose then they can be removed easily with some strategically
placed explosives. The magnets are great for finding tiny springs in
the carpet. Did you know that a magnet stops working when it's heated?
You can stick one to the burner grate and turn on the flame and it will
fall off. (and never really recovers either) Cheers
Davy

On Tue, 3 May 2005 08:22:37 +0100, "N Cook" wrote:


"Dan" wrote in message
...
I just had to post this. While ago the original hard drive went out in
my pc. I replaced it & all went well, and since I'd never looked inside
one of these, I took it apart. The beautiful, nearly "industrial art
sculpture" of the mirror platter assembly/aluminum motor, casting, all
held with cool fasteners was impressive enough, but then I started
playing with the magnets from the pickup assembly. My god, they're
strong! Neodymium, I think. So strong that I actually gave myself a
small blood blister when the 2 snapped together as I played with them.
About this same time, the door catch broke on my faithful 20 year old
clothes dryer. Not a chance of getting a replacement catch, so for the
past 2 weeks I've been propping the unused base from my drill press
against the door to hold it shut. Then it dawned on me: "I bet those
magnets from the HDD are more than strong enough to hold this thing shut
against the seal & force of the door switch". Works like a charm, in
fact I only need ONE of them! Judging from the pull now required to
open the door, it's actually tighter than it was with the original
catch! Further justification for my "never throw ANYTHING out" policy ;-)

Dan

A near neighbour managed to drop his car keys down a drain in the street
just as he was to drive to an airport. I tied an ex-5 1/4 magnet to a piece
of string vertically and he went fishing. It came up with his keys on first
attempt.

Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on

A friend rolled a tin of (expensive) paint off his moored boat into
about 15 feet of water, about 20 mins of fishing with a big magnet
retrieved it, much to his relief.

Isaac Wingfield writes:

In article ,
"Gideon" wrote:

Another good source of powerful magnets is the field
magnets from some motors. I believe that they are
becoming common in automobile starters.

I've never seen one that was anywhere near as strong as a hard drive
magnet.

Nothing you're likely to find in common motors, but very high performance
normal motors, and especially linear motors, use larger version of the
highest strength latest rare earth magnets.

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PaPaPeng writes:

On Wed, 04 May 2005 04:33:00 GMT, "James Sweet"
wrote:


"Matt" wrote in message
roups.com...
I once used a motor from an old dryer to fix a hard drive.

No, Really!


One of those huge cabinet drives that held about 5mb and had a good sized
induction motor driving the spindle?

My memory is fading since I last serviced those 20MB HDs some 20 years
ago. They weighed at least 100 lbs and took two guys to lift it
because there's no way to put one's arms around one to do any lifting.
It would also have hurt many backbones. The drive's mass was a
design decision to provide inertia to dampen out any outside
vibrations such as someone slamming a door or a heavy guy walking
nearby. Plus that voice coil's seek operations shook the whole drive
like a rat caught by a terrier. The RW head was the size of a stick
of gum and it provided us service guys a good paying job because they
crashed often enough for the computer customer to pay big bucks to be
on a service contract. I think the platters were 14 inch diameter
and when the RW head touched the surface it gouged out a deep groove
into the aluminium.

And don't forget those alignment packs that cost something like $1500
and usually got trashed because someone missed replacing one of the
heads that crashed.

The drives were tough though. Someone gave us a couple of CDC washing
machine type drives but they were several blocks away. So, we wheeled
over city streets just on their casters. Powered right up and wored for
several years without problems.

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If you don't plan to reuse the fasteners as a security measure, you can
usually break the pin off and then use a regular tool to remove them. Use
either needlenose pliers or a hammer and punch.

WT

"PaPaPeng" wrote in message
...
On Wed, 04 May 2005 03:28:28 GMT, "James Sweet"
wrote:

Did I have an oddball (don't remember the brand) or was it simply a
matter
of me being an idiot and not having a common tool?



A lot of them are metric torx.

Is there such a thing as a SAE vs metric torx? I see only a tool ID
number but no dimensions specified.

One item one should check though is if there is a centre pin in the
screw fastener's recess. If so it will require a driver tool bit with
a hole in the center to accept this pin. I think the tools are
described as security bit sets. When these security fasteners first
came out there were no tools available but I was able to get around it
by drilling the hole with a dental burr (drill bit) in the torx
driver.

Barry Lennox ) writes:

A friend rolled a tin of (expensive) paint off his moored boat into
about 15 feet of water, about 20 mins of fishing with a big magnet
retrieved it, much to his relief.

That's the sort of thing you'd see in Edmund Scientific ads and
catalogs years ago. They were one of the obvious places to get really
strong magnets before we had a wealth of items to take apart and
salvage magnets from.

Michael

Arthur Shapiro wrote:

The last time I replaced a disk drive, I couldn't find a means of opening
it to grab the magnets. It wasn't Torx, security Torx, allen, or anything
else I had in my reasonably well-equipped set of wrenches. Finally conceded
defeat and discarded it.

I ran into the same situation, but wasn't willing to simply trash the
drive (security reasons). So I drilled out the screws until I could get
inside. Cute little platters - I hated to bend them all up by jamming a
screwdriver into them ...

Bill Jeffrey

Yeah, we had those on the aircraft carrier I was on. Huge washing
machine size hard drives, with the removable packs. There were about 6
of them installed, as I recall.

One problem: Air ops was not required to tell anyone before beginning
operations, and the occasional pilot doing a fly-by was not required to
call us before performing said procedure.

Every month, at least one pilot would do a fly-by.

BOOOM

Crash Crash Crash Crash Crash

You could hear the heads getting shredded on the drives. I always
thought it was funny, but I wasn't the one that had to fix them or do
the restore.

In article A%7ee.15134$_K.13680@fed1read03,
Bill Jeffrey wrote:

Arthur Shapiro wrote:

The last time I replaced a disk drive, I couldn't find a means of opening
it to grab the magnets. It wasn't Torx, security Torx, allen, or anything
else I had in my reasonably well-equipped set of wrenches. Finally
conceded
defeat and discarded it.

I ran into the same situation, but wasn't willing to simply trash the
drive (security reasons). So I drilled out the screws until I could get
inside. Cute little platters - I hated to bend them all up by jamming a
screwdriver into them ...

Maybe you can use them around your shop. They're probably the flattest
surfaces you've ever touched.

Isaac

On Tue, 03 May 2005 19:10:46 +1200, Barry Lennox
wrote:

:On Mon, 02 May 2005 20:39:31 -0400, Dan
wrote:
:
:I just had to post this. While ago the original hard drive went out in
:
:snip
:
:catch! Further justification for my "never throw ANYTHING out" policy ;-)
:
:
:
:Ahah, me too. My barn is full of good treasures. The magnets off
:ex-Microwave magnetrons are also pretty good, not that powerful, but
:they are large. Ideal for many things around the workshop, holding
:things while welding, holding the chuck key on the side of the
:drill-press, etc ,etc.

I took the magnets out of two microwaves over the last few weeks. Ring
magnets, reasonably strong.
:
:One of the best things to strip down are old photocopiers, motors,
:switches, LV and HV PSUs, LEDs, gears, lamps and lots of other stuff.

What do you get out of those things?
:
:The stupid EU does not need their WEEE directive, I'm doing my best !!

Could you translate this? Thanks!

Dan

:
:Barry Lennox
:

On Wed, 04 May 2005 23:25:38 +1200, Barry Lennox
wrote:

:On Tue, 3 May 2005 08:22:37 +0100, "N Cook" wrote:
:
:
:"Dan" wrote in message
...
: I just had to post this. While ago the original hard drive went out in
: my pc. I replaced it & all went well, and since I'd never looked inside
: one of these, I took it apart. The beautiful, nearly "industrial art
: sculpture" of the mirror platter assembly/aluminum motor, casting, all
: held with cool fasteners was impressive enough, but then I started
: playing with the magnets from the pickup assembly. My god, they're
: strong! Neodymium, I think. So strong that I actually gave myself a
: small blood blister when the 2 snapped together as I played with them.
: About this same time, the door catch broke on my faithful 20 year old
: clothes dryer. Not a chance of getting a replacement catch, so for the
: past 2 weeks I've been propping the unused base from my drill press
: against the door to hold it shut. Then it dawned on me: "I bet those
: magnets from the HDD are more than strong enough to hold this thing shut
: against the seal & force of the door switch". Works like a charm, in
: fact I only need ONE of them! Judging from the pull now required to
: open the door, it's actually tighter than it was with the original
: catch! Further justification for my "never throw ANYTHING out" policy ;-)
:
: Dan
:
:A near neighbour managed to drop his car keys down a drain in the street
:just as he was to drive to an airport. I tied an ex-5 1/4 magnet to a piece
:of string vertically and he went fishing. It came up with his keys on first
:attempt.
:
:Diverse Devices, Southampton, England
:electronic hints and repair briefs , schematics/manuals list on
:
:A friend rolled a tin of (expensive) paint off his moored boat into
:about 15 feet of water, about 20 mins of fishing with a big magnet
:retrieved it, much to his relief.

Back when I was working on the docks one day something dropped into the
bilge of the boat. I dropped a large magnet from a piece of thin nylon
cord and found a great screwdriver that I have to this day. I have that
horseshoe magnet as well, bought for a pretty penny at the hardware
store.

On 03 May 2005 17:26:29 -0400, Sam Goldwasser
wrote:

(Arthur Shapiro) writes:
:
: In article , Dan wrote:
: I just had to post this.
:
: The last time I replaced a disk drive, I couldn't find a means of opening
: it to grab the magnets. It wasn't Torx, security Torx, allen, or anything
: else I had in my reasonably well-equipped set of wrenches. Finally conceded
: defeat and discarded it.
:
: Did I have an oddball (don't remember the brand) or was it simply a matter of
: me being an idiot and not having a common tool?
:
:You'd have to describe the screw heads or whatever. I've yet to come up
:against a dead harddrive I couldn't get open reasonably non-destructively.
:
I read a post from someone suggesting that some of these drives may have
some toxic chemicals in them. Is this true or false?

On 4 May 2005 04:05:22 -0700, "Ignorant genius"
wrote:

:Arthur Shapiro wrote:
: In article , Dan
wrote:
: I just had to post this.
:
: The last time I replaced a disk drive, I couldn't find a means of
pening
: it to grab the magnets. It wasn't Torx, security Torx, allen, or
:anything
: else I had in my reasonably well-equipped set of wrenches. Finally
:conceded
: defeat and discarded it.
:
: Did I have an oddball (don't remember the brand) or was it simply a
:matter of
: me being an idiot and not having a common tool?
:
: Art
:
:
:I had the same problem. Just use some wire cutters to get the screws
:broken loose then they can be removed easily with some strategically
laced explosives. The magnets are great for finding tiny springs in
:the carpet. Did you know that a magnet stops working when it's heated?
:You can stick one to the burner grate and turn on the flame and it will
:fall off. (and never really recovers either) Cheers
avy

That's probably because the magnetic dipoles whose cumlulative magnetic
field give the magnet its net power are able to rearrange position when
the metal gets hot enough. Once their original orientation is lost, they
never regain it when cooled. Never, that is, unless they cool in a
strong magnetic field (which would cause them all to line up parallel
again before the cooling process)!

Dan