We had a hard disk die in our home network server. Fortunately, it was
mirrored & nothing was lost.

Partly out of curiosity and partly to make sure the personal files were
permanently inaccessible, I've taken it apart. Most of the innerds are
recognizable from previous fits of such surgery, but there's something
new in this one.

It's a retangular capsule, approximately 7/8" long, and about 3/8"
square, made of clear plastic, with a soft white concave seal on top.
Inside, it is filled with tiny (~1/32" diameter or smaller) black beads.

I figure it's either desicant (never seen black desicant before), or
vibration damping material (like lead shot), only I can't imagine that
they allow that much lead in anything commercial these days. I pried it
out, and it appears to be vented to the outside world through a tiny
hole (and an eqaully tiny labyrinth of small passages), and it's quite
light, so lead is out. Venting desicant to the outside world doesn't
make much sense either, unless the white stuff is some sort of
semi-permeable membrane.

Any ideas?

Thanks!

Doug White

Doug White wrote:

We had a hard disk die in our home network server. Fortunately, it was
mirrored & nothing was lost.

Partly out of curiosity and partly to make sure the personal files were
permanently inaccessible, I've taken it apart. Most of the innerds are
recognizable from previous fits of such surgery, but there's something
new in this one.

It's a retangular capsule, approximately 7/8" long, and about 3/8"
square, made of clear plastic, with a soft white concave seal on top.
Inside, it is filled with tiny (~1/32" diameter or smaller) black beads.

I figure it's either desicant (never seen black desicant before), or
vibration damping material (like lead shot), only I can't imagine that
they allow that much lead in anything commercial these days. I pried it
out, and it appears to be vented to the outside world through a tiny
hole (and an eqaully tiny labyrinth of small passages), and it's quite
light, so lead is out. Venting desicant to the outside world doesn't
make much sense either, unless the white stuff is some sort of
semi-permeable membrane.

Any ideas?

Could it be an air filter? The disk compartment in a hard drive isn't sealed
but is open to the atmosphere through a very fine filter, fine enough to take
out the particles of cigarette smoke.

Tove

"Doug White" wrote

I figure it's either desicant (never seen black desicant before), or ...


Possibly an activated-carbon filter, possibly for chlorine or ammonia.

How old was this drive?

-- TP

"Doug White" wrote in message
...
I figure it's either desicant (never seen black desicant before), or
vibration damping material (like lead shot), only I can't imagine that
they allow that much lead in anything commercial these days. I pried it
out, and it appears to be vented to the outside world through a tiny
hole (and an eqaully tiny labyrinth of small passages), and it's quite
light, so lead is out. Venting desicant to the outside world doesn't
make much sense either, unless the white stuff is some sort of
semi-permeable membrane.

Any ideas?

Bit of a long shot, perhaps. You mentioned a labyrinth.
I guess it was some sort of breathing arrangement which filters out
humidity. Back in the 60s (working in military avionics) we used fine
coiled up tubes to allow sealed equipment containers to vent to atmospheric
pressure, without the insides getting damp. Remember thinking it must be
magic, but I even have vague memories of reading some academic paper on the
subject.

--
M Stewart
Milton Keynes, UK
http://www.megalith.freeserve.co.uk/oddimage.htm

In article ,
"Malcolm Stewart" wrote:

"Doug White" wrote in message
...
I figure it's either desicant (never seen black desicant before), or
vibration damping material (like lead shot), only I can't imagine that
they allow that much lead in anything commercial these days. I pried it
out, and it appears to be vented to the outside world through a tiny
hole (and an eqaully tiny labyrinth of small passages), and it's quite
light, so lead is out. Venting desicant to the outside world doesn't
make much sense either, unless the white stuff is some sort of
semi-permeable membrane.

Any ideas?

Bit of a long shot, perhaps. You mentioned a labyrinth.
I guess it was some sort of breathing arrangement which filters out
humidity. Back in the 60s (working in military avionics) we used fine
coiled up tubes to allow sealed equipment containers to vent to atmospheric
pressure, without the insides getting damp. Remember thinking it must be
magic, but I even have vague memories of reading some academic paper on the
subject.

May be called a swan tube? I recall that Pasteur used this trick to
keep germs from entering his flasks.

If the tube volume is more than 10% of the volume of the container, then
the natural variation in barometric pressure will not be able to cause
"breathing" (and exchange with the atmosphere).

Joe Gwinn

Keywords:
In article , "tonyp" wrote:

"Doug White" wrote

I figure it's either desicant (never seen black desicant before), or ...


Possibly an activated-carbon filter, possibly for chlorine or ammonia.

How old was this drive?

I like the activated charcoal idea. There's lots of surface area with
all the little beads. Probably to keep air polutants from eating the
drive.

The drive was only about two years old. The network server it was in
primarily gets used for backups, and didn't have particularly hard use.
I've never had much use for Maxtor drives, but it's what came with the
server. It's been replaced with a Seagate, which is what the mirror
drive is.

Doug White

snip
The drive was only about two years old. The network server it was in
primarily gets used for backups, and didn't have particularly hard use.
I've never had much use for Maxtor drives, but it's what came with the
server. It's been replaced with a Seagate, which is what the mirror
drive is.
Doug White
========================
I've had good results with the large capacity western digitals,
and what ever iomega uses for the usb hard drives also seems to
stand up, altho I use these mainly for back-up and data tranfer.

Anyone care to give feedback on their personal experiences with
the various brand/model hard drives?

Uncle George

On Tue, 10 Jan 2006 01:54:59 GMT, Doug White wrote:

It's a retangular capsule, approximately 7/8" long, and about 3/8"
square, made of clear plastic, with a soft white concave seal on top.
Inside, it is filled with tiny (~1/32" diameter or smaller) black beads.

I figure it's either desicant (never seen black desicant before),

I've seen dissicant in hard drives, but as you say, never black. A
google search for "black dessicant media" is...unenlightening...

Doug White wrote:
We had a hard disk die in our home network server. Fortunately, it was
mirrored & nothing was lost.

Partly out of curiosity and partly to make sure the personal files were
permanently inaccessible, I've taken it apart. Most of the innerds are
recognizable from previous fits of such surgery, but there's something
new in this one.

It's a retangular capsule, approximately 7/8" long, and about 3/8"
square, made of clear plastic, with a soft white concave seal on top.
Inside, it is filled with tiny (~1/32" diameter or smaller) black beads.

I figure it's either desicant (never seen black desicant before), or
vibration damping material (like lead shot), only I can't imagine that
they allow that much lead in anything commercial these days. I pried it
out, and it appears to be vented to the outside world through a tiny
hole (and an eqaully tiny labyrinth of small passages), and it's quite
light, so lead is out. Venting desicant to the outside world doesn't
make much sense either, unless the white stuff is some sort of
semi-permeable membrane.

Any ideas?

Thanks!

Doug White
The white stuff could be a semi-permeable membrane. Gore-Tex markets it
as such for instrumentation breathers.

F. George McDuffee wrote:

Anyone care to give feedback on their personal experiences with
the various brand/model hard drives?

go to the oracle
http://www.storagereview.com/

It's the cure all virus medicine.

Greg