Why are HDD platters harder than the floppy/ZIP discs?

Hi:

I have a question just out of curiosity.

I notice with ZIP discs and floppies, the disc is a soft dark-brown
round film-like material that can easily be shredded -- with paper-
shredder -- to remove confidential information.

However, the magnetic platters in HDDs are much harder and metallic.

Why don't they make the hard-disc-drive platters soft like the discs
of floppies and ZIPs? It would be so much easier to remove unwanted
confidential information then. Simply unscrew the HDD, remove the soft
platters and dump them into a paper-shreder.

To remove personal info from an HDD requires that the platters be
heated beyond Curie point to eliminate all magnetic data. This is
extremely inconvenient and dangerous because of the high temperatures
required.


Thanks a bunch,

Green

 

Posted to 24hshd only

GreenXenon recklessly crossposted to:
Newsgroups: alt.computer, 24hoursupport.helpdesk, alt.computer.security,
alt.privacy, comp.sys.ibm.pc.hardware.storage

Don't crosspost your message to as many different groups as you can
imagine that it might possibly pertain.

Don't crosspost your message to any groups which you don't subscribe and
read regularly and are thus familiar with.

If you are reading all or any of those groups above and are familiar with
their discussion content, then you should be familiar with which *one* of
them would be the best one to post your questions. Post your question to
that one group, not 5 different disparate groups.

It is highly likely that someone who answers your question/s will not be
regularly reading those 5 groups and also should not crosspost in the
manner that you did. People should not be crossposting messages into
groups they don't read, because some or many respondents to a message are
likely to trim the crossposted groups they don't read.

Floppy and zip media are a very different technology for a very different
purpose than a modern hdd or even a not-so-modern hdd. I'm very glad
that my hdd/s work as they do and not as floppies or zips.

 

Several reasons: 1. Rotation speed. Hard drives spin at several thousand
RPM (7,000-10,000), Floppies at under 500. You can actually tell by their
sound when a revolution is finished - less than a second, but definitely
discernable. 2. Head gap. Floppy disk heads sit on the order of 1 mm from
the surface of the disk and frequently make contact with it. Hard drive
heads float less than 10 millionths of an inch over the surface and due to
the speed involved will destroy the surface if they contact it. However if
you have to do more than a full format, that's only the start of your
security concerns IMHO.

 

In "Mike Easter"

Judging from this character's posting history, he just wanders from
group to group asking strange questions.

 

Because if they made "hard" drives floppy like you want they couldn't
call them HARD drives dimwit!

 

Is it possible to hermetically-seal the soft disc of a floppy/zip? Of
course the spin speed would still have to be slow to prevent the soft
material from being injured. Right?

Is it also true that in order to have the same amount of storage
space, that the soft floppy material would need to be bigger in
diameter than the hard platter of an HDD?

IOW, is it possible for a soft floppy disc to have the same data
density as a hard HDD platter?

 

Meaning?

 

Yes, it's possible, but why do it?



Of

Yes. The reason for speed is that the area of a data cluster can be smaller.

NO, because the floppy spins at a fraction of the speed.

 

Meaning?

 

When you format a disk you make it pretty well impossible for anyone but
LEA to justify or even be able to recover information from them. A DoD
spec overwrite will negate this as well. Anyone who actually worries about
destroying the physical platters or their media directly is spending effort
in misdirected efforts that gains little if anything.

 

Oh my... Wow.. That's incredibly funny, chucktard.

 

GreenXenon wrote

Dont forget what curiosity did to the cat.

Because you get much higher bit densitys with rigid platters
and its completely trivial to wipe them magnetically and you
can reuse the platters when you do that.

Much easier to use a decent security wipe like dban.

Wrong. All you need is a decent security wipe like dban.

Nothing dangerous about a properly designed furnace.

And shredded floppys have actually been recovered.

 

No they arent. They always have a filtered vent that allows pressure equalisation.

It isnt the spin rate that allows the much higher bit density.

In fact hard drive heads fly. Floppy drives heads dont.

Nope, modern hard drives have embedded servo info that handles that
fine as the platter expand and contract due to changing temperatue.

They arent all glass.

In fact the real reason is just the much higher bit densitys possible with rigid platters.

 

In fact they always make contact and dont fly like a hard drive head does.

 

Yes, and hard drives arent in fact hermetically sealed anyway.

Nope. It would be possible to make flexible
material that could be spun at those speeds.

Thats true in the sense that the bit densitys are much higher with rigid platters.

Nope.

And its all completely pointless anyway when its so completely trivial to
use a decent security wipe like dban that completely wipes rigid platters.

The only thing it cant wipe is spared sectors.

 

Hey, GreenGlow, did you ever get answers to these questions yet?
What is Sphygmo-thermic dissociation?
When a neuron is stimulated, it depolarizes. When relaxed, it
hyperpolarizes?
They chased you from comp.dsp, sci.physics & sci.med.cardiology for
being a troll.
Grow up.....if you are ALLOWED, that is????

 

The head in a floppy drive rubs along the surface - like a cassette tape.
HDD has no contact - so no wear and can turn much faster. ( You ever try
installing a big app from floppy ? 25mb would take 20 minutes to load 23
floppies. on a HDD it takes - a second.) From tech school 25+ years ago , I
remember the teacher explaining the relationship between the heads and the
platters on a HDD as a "727 flying at 500 mph 12 inches off the ground " -
so no room for error. At high RPM's , if those "platters" were 'like a
floppy ' they would be flapping in the wind. In a HDD the heads "fly"
above the "air pressure surface" created by the high speed. They are spring
loaded so that - at a given speed they are x microinches from the platter -
at the range were the data can be read. Too far away and magnetic field is
unreadable. Too close = surface contact . A floppy WILL wear out if used
over and over ( wear) BUT, since there is no actual contact , ideally there
is no surface wear on HDD.
In a real secure/secret environment, (To remove personal info from an HDD
requires that the platters be heated beyond Curie point) the way to "be sure
that the data is removed" from HDD: open case , remove platters and put them
through a shredder. There is a log to fill out by those involved. Companies
that need that level of security have that equipment - and the output is
like talcum powder.

 

I have a gas stove at home. If I heat the platters directly over the
flame, will that be hot enough to be beyond the Curie point of the
platters?

 

I can't imagine many people use " The Curie point " to reuse the HDD
"The Curie point of a ferromagnetic material is the temperature above which
it loses its characteristic ferromagnetic ability (768°C or 1414 °F for
iron)"

 

True. The platters become unusable after beyond-Curie heating.
However, is the gas stove flame hot enough to do this? I'm thinking of
heating the platters of my old HDD over the gas stove flames to
completely eliminate all the confidential info in it. Will it work?