What are the shiny CDROM-sized platters in an old desktop disk drive made
out of?

I glued two of them together so that the offset covered the center hole to
use as an indestructable traveling shaving mirror.

A friend said they won't pass TSA security but they're not sharp. They are
just really shiny and really flat.

What are they made out of anyway?

Elmo wrote

What are the shiny CDROM-sized platters in an old desktop disk drive made out of?

They are usually glass or aluminium.

I glued two of them together so that the offset covered the
center hole to use as an indestructable traveling shaving mirror.

A friend said they won't pass TSA security but they're not sharp.
They are just really shiny and really flat.

What are they made out of anyway?

They are usually glass or aluminium.

Elmo wrote:
What are the shiny CDROM-sized platters in an old desktop disk drive made
out of?

I glued two of them together so that the offset covered the center hole to
use as an indestructable traveling shaving mirror.

A friend said they won't pass TSA security but they're not sharp. They are
just really shiny and really flat.

What are they made out of anyway?
Hi,
They are metal platter.

On Tue, 22 Jun 2010 04:48:56 +0000 (UTC), Elmo
wrote:

What are the shiny CDROM-sized platters in an old desktop disk drive made
out of?

I glued two of them together so that the offset covered the center hole to
use as an indestructable traveling shaving mirror.

A friend said they won't pass TSA security but they're not sharp. They are
just really shiny and really flat.

What are they made out of anyway?

I've taken them apart but I didnt' try bending them. If you really
think the tsa will complain, bring another one you can bend for them.
Maybe that will help, if they really do complain. Or bend the double
one you're bringing and use the bent part as a stand.

On Leno tonight, Headlines. someone was photographing a pedestrian,
but he turned his head away and put a file folder between his head and
the camera. Unfortunately the glass window behind him gave a perfect
reflection. Something he might not have known from his vantage
point!

On Jun 22, 2:12*am, mm wrote:
On Tue, 22 Jun 2010 04:48:56 +0000 (UTC), Elmo

wrote:
What are the shiny CDROM-sized platters in an old desktop disk drive made
out of?

I glued two of them together so that the offset covered the center hole to
use as an indestructable traveling shaving mirror.

A friend said they won't pass TSA security but they're not sharp. They are
just really shiny and really flat.

What are they made out of anyway?

I've taken them apart but I didnt' try bending them. *If you really
think the tsa will complain, bring another one you can bend for them.
Maybe that will help, if they really do complain. *Or bend the double
one you're bringing and use the bent part as a stand.

On Leno tonight, Headlines. someone was photographing a pedestrian,
but he turned his head away and put a file folder between his head and
the camera. *Unfortunately the glass window behind him gave a perfect
reflection. * Something he might not have known from his vantage
point!

Any HDD I've taken apart I'd be concerned about from a safety
standpoint... the platters don't "bend" at all, and if you try too
forcefully they will explode into a whole mess of tiny, sharp shards.
Good if you're trying to destroy one that you're decommissioning; not
so good if you've packed it with your underwear.

nate

On Tue, 22 Jun 2010 08:48:40 -0700 (PDT), N8N
wrote:

On Jun 22, 2:12*am, mm wrote:
On Tue, 22 Jun 2010 04:48:56 +0000 (UTC), Elmo

wrote:
What are the shiny CDROM-sized platters in an old desktop disk drive made
out of?

I glued two of them together so that the offset covered the center hole to
use as an indestructable traveling shaving mirror.

A friend said they won't pass TSA security but they're not sharp. They are
just really shiny and really flat.

What are they made out of anyway?

I've taken them apart but I didnt' try bending them. *If you really
think the tsa will complain, bring another one you can bend for them.
Maybe that will help, if they really do complain. *Or bend the double
one you're bringing and use the bent part as a stand.

On Leno tonight, Headlines. someone was photographing a pedestrian,
but he turned his head away and put a file folder between his head and
the camera. *Unfortunately the glass window behind him gave a perfect
reflection. * Something he might not have known from his vantage
point!

Any HDD I've taken apart I'd be concerned about from a safety
standpoint... the platters don't "bend" at all, and if you try too
forcefully they will explode into a whole mess of tiny, sharp shards.

I retract my suggestion.

Did they teach you the word potsherd in high school, or did you read
the word in museums, regarding broken things found at excavations of
ancient man?

For decades my brother and I both pronounced the word pots herd,
until one day I looked at it and realized it was pot sherd.


Good if you're trying to destroy one that you're decommissioning; not
so good if you've packed it with your underwear.

nate

On Tue, 22 Jun 2010 14:47:23 +0000, DA wrote:
A bit of a strange choice of material for *traveling* shaving mirror

We must be talking about different things because these two CDROM-sized
mirrors are extremely light - you can barley feel them in your hands. No
mirror I've ever seen in my life is this light. Or as indestructible.

As for traveling, the two platters glued together are really shiny and
extremely light and they don't break when I drop them and they're exactly
the right oblong size (when glued together offset) for a face ... so it's a
PERFECT traveling shaving mirror IMHO.

I've had glass mirrors (which obviously shatter); I've had plastic mirrors
(which scratch too easily and aren't all that reflective; and I've had even
used nicely handled old round concave (or are they convex?)
Japanese-motorcycle mirrors (which eventually broke due to the glass).

Most store-bought mirrors have more "frame" in them than mirror, whereas
these mirrors are 100% mirror without any frame or handle to have to carry.
Many store-bought mirrors come apart after repeated use in the shower (I
always shave in the shower).

So far, I can't think of a more perfect traveling shower-shaving mirror ...
as long as the TSA will let it through.

Based on the responsese so far, I'm guessing, since the material is non
magnetic, and it's certainly not glass, that it must be extremely highly
polished aluminum.

What are these polished aluminum platters used for anyway (in the HDD)?

Elmo wrote:
On Tue, 22 Jun 2010 14:47:23 +0000, DA wrote:
A bit of a strange choice of material for *traveling* shaving mirror

We must be talking about different things because these two
CDROM-sized mirrors are extremely light - you can barley feel them in
your hands. No mirror I've ever seen in my life is this light. Or as
indestructible.

As for traveling, the two platters glued together are really shiny and
extremely light and they don't break when I drop them and they're
exactly the right oblong size (when glued together offset) for a face
... so it's a PERFECT traveling shaving mirror IMHO.

I've had glass mirrors (which obviously shatter); I've had plastic
mirrors (which scratch too easily and aren't all that reflective; and
I've had even used nicely handled old round concave (or are they
convex?) Japanese-motorcycle mirrors (which eventually broke due to
the glass).

Most store-bought mirrors have more "frame" in them than mirror,
whereas these mirrors are 100% mirror without any frame or handle to
have to carry. Many store-bought mirrors come apart after repeated
use in the shower (I always shave in the shower).

So far, I can't think of a more perfect traveling shower-shaving
mirror ... as long as the TSA will let it through.

Based on the responsese so far, I'm guessing, since the material is
non magnetic, and it's certainly not glass, that it must be extremely
highly polished aluminum.

What are these polished aluminum platters used for anyway (in the HDD)?

They have a very thin oxide coating on them for the magnetic surface.

They are so highly polished because they need to be very smooth since
the heads fly so close to the surface so the magnetic domains are as
small as possible so the bit density is as high as possible.

On Wed, 23 Jun 2010 07:30:51 +1000, Rod Speed wrote:

They are so highly polished because they need to be very smooth since
the heads fly so close to the surface so the magnetic domains are as
small as possible so the bit density is as high as possible.

I thought they were reflective mirrors for the lasers or something.

I didn't realize these were the actual magnetic material. They are soooo
smooth and shiny. I expected concentric circular lines of something or
other like the bottom of a CDROM or DVD once it has been burned.

These platters are so polished that you can't make out a single bit of
"thin oxide" coating. Shinier than any metal or plastic mirror I've ever
seen and more indestructible than glass.

In short, they're the perfect wet-shower traveling mirror if TSA will allow
them through.

In article , dcdraftworks@Use-Author-
Supplied-Address.invalid says...

What are these polished aluminum platters used for
anyway (in the HDD)?


That's where the data is stored. In little magnetic spots.


--
Get Credit Where Credit Is Due
http://www.cardreport.com/
Credit Tools, Reference, and Forum

Elmo wrote:
Rod Speed wrote

They are so highly polished because they need to be very smooth
since the heads fly so close to the surface so the magnetic domains
are as small as possible so the bit density is as high as possible.

I thought they were reflective mirrors for the lasers or something.

Nope, there are no lasers inside those hard drives.

I didn't realize these were the actual magnetic material. They are soooo
smooth and shiny. I expected concentric circular lines of something or
other like the bottom of a CDROM or DVD once it has been burned.

Nope, there are no visible lines unless the drive has had a head crash.

These platters are so polished that you can't make out a single bit of
"thin oxide" coating. Shinier than any metal or plastic mirror I've ever seen

Yes, thats the result of that very perfect surface.

and more indestructible than glass.

Some were in fact made of glass.

In short, they're the perfect wet-shower traveling mirror if TSA will allow them through.

I wouldnt like to predict what some trained ape will make of them.

In article ,
Elmo wrote:

I didn't realize these were the actual magnetic material. They are soooo
smooth and shiny. I expected concentric circular lines of something or
other like the bottom of a CDROM or DVD once it has been burned.

These platters are so polished that you can't make out a single bit of
"thin oxide" coating. Shinier than any metal or plastic mirror I've ever
seen and more indestructible than glass.

Older drives did use an oxide (like "ferric" magnetic tape cassettes).

Newer drives, such as the one which donated its platters for your
mirror, have a more complex magnetic recording layer. It's a complex
coating of alloys, vacuum-deposited on the polished aluminum (or glass
or ceramic) surface using a process known as sputtering. The
resulting magnetic layer has an extremely fine "grain" structure,
which allows for small magnetic domains and thus lots of storage per
area.

You won't be able to see the lines which make up the individual data
tracks... they aren't physically carved or burned into the magnetic
coating, and consist only of varying patterns of magnetism.

Yes, the surface is very smooth and shiny. It needs to be - the disk
drive heads "fly" over the surface, at a height far less than the
diameter of a human hair. Even a particle of cigarette smoke is too
big to fit between the "flying head" and the surface.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

On 22/06/2010 2:48 PM, Elmo wrote:
What are the shiny CDROM-sized platters in an old desktop disk drive made
out of?

I glued two of them together so that the offset covered the center hole to
use as an indestructable traveling shaving mirror.

A friend said they won't pass TSA security

You're suggesting that TSA use any sort of rational criterion when
deciding what to let through?

Sylvia.

On Jun 22, 6:40*pm, "Rod Speed" wrote:
Elmo wrote:



I wouldnt like to predict what some trained ape will make of them.


I wouldn't take a chance.

I'd put them in a protective sleeve. I'd use one of those free AOL
disk sleeves you find in piles everywhere.

On Tue, 22 Jun 2010 21:09:28 +0000 (UTC), Elmo
wrote:


I've had glass mirrors (which obviously shatter); I've had plastic mirrors
(which scratch too easily and aren't all that reflective; and I've had even
used nicely handled old round concave (or are they convex?)

Convex. Easy to remember. The other ones are like caves, and they're
called concave.

Japanese-motorcycle mirrors (which eventually broke due to the glass).