Subject: Re: Fun With Scrap Hard drives

From: [email-masked] (Tim Nye)
Date: Fri, 26 Jan 1996 16:09:42 GMT

In article <[email-masked]> Randolph Lee <[email-masked]> writes:

>the 4 magnets used to move the heads are amazingly strong for their 
>size... I would guess they are some sort of rare earth sintered 
>type... lots of use for these in the shop.... but the chrome plating 
>is comeing off 2 of them and one shatered when it was dropped... 
>they seem a bit brittle.

A drive I dismantled once had four of these voice-coil magnets (probably 1/
2" x 1/2" x 1/16" each), each pair glued steel backing plate.  One pair 
was able to pick up a 40 pound lathe chuck.  Pretty amazing.

Tim

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From: [email-masked] (W. Kaiser)
Date: 26 Jan 1996 18:49:03 GMT

Randolph Lee ([email-masked]) wrote:
> My local ISP Tech brought a vintage 1991 1 gig 5" seagate Hard drive 
> into the shop and we had fun tearing it apart...

> the Disk platers themselves  (8 of them) were very unifoum in 
> thickness at 0.0746 + or - about .0002.... 4 of the 8 were .07450... 
> to the limits of my metrology equipment... = or - .00005 there use 
> as packing seems obvious... (they would aslo make a nice set of wind 
> chimes I think)

> the spacer rings at 0.1704 were also within those above limits

Sounds like a Tesla turbine waiting to happen.

--
Bill Kaiser
[email-masked]

There are three ways to do a job: good, cheap, and quick.
You can have any two.
A good, cheap job won't be quick.
A good, quick job won't be cheap.
A cheap, quick job won't be good.

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From: Randolph Lee <[email-masked]>
Date: Thu, 25 Jan 1996 12:25:36 +0000

many of the bits a chunks will be found to be of use in the  HSM 
shop...

the wires to the heads were about 0.0013 in dia and most of the 
other parts seemed to be of a very high standard... it was fun to 
see the guts of the thing and gain a better understanding of how it 
works but asside from the case and the nice torix SS hardware I 
don't know what I will do with the misc parts... I may use the main 
board as the striker for a wind chime made from some of the disks... 
and the head carrier arms look like I might use them for'something' 

the bottom motor bearing was shot (it was amazingly badly worn) but 
the top one seemed to be fine there was evidence of a head crash on 
3 of the platters as well...

if the chance to scrap onew of these units comes your way don't pass 
it up... I think you will find it as fun as I did...

~R

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From: [email-masked] (Jonathan M. Elson)
Date: 26 Jan 1996 06:32:34 GMT

Randolph Lee ([email-masked]) wrote:
: My local ISP Tech brought a vintage 1991 1 gig 5" seagate Hard drive 
: into the shop and we had fun tearing it apart...

Yes, I always grab a hard disk of any size I find being thrown out.  There
are bearings, lots of small aluminum parts, hardware, magnets, a brushless
DC 3600 RPM motor (most of the newest drives have the motor control 
integrated with the microprocessor that runs the whole drive; too bad) and
just a whole lot of interesting parts that can wait in the junk box until
you need a part 'just like that one'.

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From: [email-masked] (Ray Spinhirne)
Date: 27 Jan 1996 22:58:58 GMT

Jonathan M. Elson ([email-masked]) wrote:
: Randolph Lee ([email-masked]) wrote:
: : My local ISP Tech brought a vintage 1991 1 gig 5" seagate Hard drive 
: : into the shop and we had fun tearing it apart...

: Yes, I always grab a hard disk of any size I find being thrown out.  There
: are bearings, lots of small aluminum parts, hardware, magnets, a brushless
: DC 3600 RPM motor (most of the newest drives have the motor control 
: integrated with the microprocessor that runs the whole drive; too bad) and
: just a whole lot of interesting parts that can wait in the junk box until
: you need a part 'just like that one'.

If you want really big magnets try to find some of the old "washing machine"
type CDC 80 or 300 meg drives.  Lots of AL, stainless screws, little
precision roller bearing, 1/2 HP motor, high precision spring loaded bearing
on the disk shaft and lots of hi amp DC power.  In addition to this usually
a pretty heafty welded steel cabinet with casters.  Pretty amazing to compare
those 1970 model 80 meg drives with the current 4 gig drives which are 
smaller than most hardcover books.

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From: [email-masked] (Jim Naylor)
Date: Sun, 28 Jan 1996 21:02:25 -0600

> smaller than most hardcover books.

I've had one of these lying around for a long time (of course) always
intending to see if the 12 inch platter could be used as a lap. But what
to do with the slurry? :>)  Seems a little ironic when you consider the
lengths required to keep out the tiniest dust particle, not to mention
abrasives...

-- 
Jim Naylor                             [email-masked]