peter@aucs.UUCP (10/21/87)
Here's a simple question: I teach an Intro to Mac course, and one
thing that I demonstrate is how to format a new disk. After the class
I end up with 15 formatted disks that I want to use again for the same
purpose the next time I teach the class. So, I have to "uninitialize"
them. The only way I've found to do this quickly is by starting to
reformat them and then boot the machine while the formatting is going
on. Pretty crude, and in particular slow, but it does the trick--I end
up with a disk that the Mac want to initialize when I insert it in a
drive. Does anyone know of a quick and dirty way to do this? I.e., does
anyone know of a way to "unformat" a disk quickly (or a portion of a disk).
Any ideas would be appreciated.
Peter Steele Acadia Univ. Wolfville NS Canada B0P1X0 (902)542-2201x121
UUCP:{uunet|watmath|utai|garfield}dalcs!aucs!Peter BITNET:Peter@Acadiapsych@watdcsu.UUCP (10/23/87)
If you have a bulk tape eraser for audio/vidio tapes use it. Its very fast and does a good jumble job. Richard Crispin Dept. of Psychology University of Waterloo Waterloo, Ont. Canada N2L 3G1 (519)885-1211 ext 2879
kwallich@hpsmtc1.HP.COM (Ken Wallich) (10/23/87)
/ peter@aucs.UUCP (Peter Steele) / 7:35 am Oct 21, 1987 / >Does anyone know of a quick and dirty way to do this? I.e., does >anyone know of a way to "unformat" a disk quickly (or a portion of a disk). >Any ideas would be appreciated. Well, I have a method that works. I don't think it has any adverse affects, but if anyone knows otherwise, feel free to correct me. The method I use is to take a moderatley powerful magnet, and run it across the disc (yes, magnatism passes through the plastic). The theory behind this is that a Floppy disc is just like a cassette tape, but different. The information as to what is "formatted" and what isn't is just a series of ordered electrons on the surface of the disc. Using a magnet scrambles the electrons and it now is "unformatted". I have been doing this since my CP/M days and haven't lost a floppy yet.
wmartin@ut-emx.UUCP (Wiley) (10/23/87)
Get a fairly powerful magnet and rub it briskly on the outside of the plastic case of the disk. This will scramble the magnetic stuff just enough that the Mac won't recognize the disk as readable. I was able to do this once using the magnets in my Walkman headphones. -w
jspear@afit-ab.arpa (Jon L. Spear) (10/23/87)
The "best" way to make a formatted disk uninitialized is to degauss it. This can be done in a few seconds with a fairly inexpensive handheld device intended for erasing cassette tapes, and can be bought at your neighborhood Radio Shack. Of course, all information on the disk (and any other disks within a few inches of the device) will be erased. So be careful. In a pinch, a small (but bigger than the average stick-paper-on- refrigerator magnet) permanent magnet passed over the diskette shell will erase enough of a disk to make it unreadable such that the Mac will think it uninitialized. However, too powerful a magnet could (has never happened to me) damage the disk. Also, a determined person will probably be able to read some information from these disks. -Jon (jspear@afit-ab.arpa - return address above may be wrong)
seiffert@silver.bacs.indiana.edu (10/23/87)
To do the job especially quick and dirty, purchase a fairly strong
magnet at some hardware or toy store, and then you can zap disks
at your liesure. All fifteen at once most likely.
Of course, I wouldn't have my $300 dollar word processing program
anywhere nearby if I were you. Not even in the same building, but
that's just paranoid me.
In fact, I recall some company marketed an electromagnet for just
this purpose. Unfortunately I couldn't tell you the name or where
to get it, but perhaps a local computer store might have such
information.
__________________________________________________________________
"May the forces of evil become confused on the way to your house."
-- George Carlin
Sincerely,
Phaedrus
(Bipedal Carbon-based Land Mammal at large)
Indiana University at Bloomington
seiffert@silver.bacs.indiana.edudwb@apple.UUCP (David W. Berry) (10/23/87)
In article <464@aucs.UUCP> peter@aucs.UUCP (Peter Steele) writes: >drive. Does anyone know of a quick and dirty way to do this? I.e., does >anyone know of a way to "unformat" a disk quickly (or a portion of a disk). >Any ideas would be appreciated. Go down to Radio Shack and get a bulk tape eraser. That's worked fine for me. -- David W. Berry dwb@well.uucp dwb@Delphi dwb@apple.com 973-5168@408.MaBell Disclaimer: Apple doesn't even know I have an opinion and certainly wouldn't want if they did.
sebruun@ihlpa.ATT.COM (Bruun) (10/23/87)
In article <464@aucs.UUCP>, peter@aucs.UUCP (Peter Steele) writes: > Here's a simple question: I teach an Intro to Mac course, and one > thing that I demonstrate is how to format a new disk. After the class > I end up with 15 formatted disks that I want to use again for the same > purpose the next time I teach the class. So, I have to "uninitialize" > them. The only way I've found to do this quickly is by starting to > reformat them and then boot the machine while the formatting is going > on. Pretty crude, and in particular slow, but it does the trick--I end > up with a disk that the Mac want to initialize when I insert it in a > drive. Does anyone know of a quick and dirty way to do this? I.e., does > anyone know of a way to "unformat" a disk quickly (or a portion of a disk). Piece of the proverbial cake, Peter. Get yourself a bulk tape eraser. (Try Radio Shack or some such.) Run the disks over for a couple of seconds. Voila!! Unformatted disks, which the Mac will report to be "unreadable" just like when you stick 'em in brand new out of the box. (Any strong magnet will do the job, of course. I just happen to have one of these gizmos, so that's what I use. By the way, should you have a disk you're having trouble initializing, this will often render it useable again, at some risk of course!) Steve Bruun AT&T Bell Labs Naperville, IL ihnp4!ihlpa!sebruun
dmw3@ur-tut.UUCP (David Walsh) (10/24/87)
I know that everyone has their favorite method for making an unformated
disk, but you should know that their are different ways of doing it and
that your Mac will respond differently to each way.
The easiest method is to get a magnet/bulk eraser and mess up the alignment
of the particles on the disk. Easily done by waving the magnet/eraser over
the disk. When you insert the disk again it will say "This disk is unformatted,
do you want to initialize?"
Another method is to destroy the boot block & directory blocks so that the
Mac will not recognize that it is a Mac disk. All you have to do is take
your favorite block editor and zero those blocks. This time inserting the disk
will get you the dialog but with the message "This is not a Macintosh disk, do
you want to initialize?"
While you still get the same dialog this could confuse some beginning Mac
students, and I reccomend the first method. However, the second box is a
message that they should be told about, as they might see it when their disks
decide to crash. If they don't initialize it (i.e. the hit the <eject> button)
the disk might still be repairable.
I realize that I answered more than was asked, but it might be useful to
some people out their who are just starting out. Hope you can make use of
this info.
Happy hacking,
Dave Walsh @ rochester!ur-tut!dmw3 (or something like that)isle@dartvax.UUCP (Ken Hancock) (10/24/87)
In article <464@aucs.UUCP> peter@aucs.UUCP (Peter Steele) writes: >...I have to "uninitialize" Have you tried : Sticking them in a strong magnetic field? An electro magnet for instance? That'll do the trick. If you don't have access to one of those, try sticking it under a telephone. That also usually destroys them. Ken -- Ken Hancock UUCP: isle@dartvax BITNET: isle@u2.dartmouth.edu DISCLAIMER: If people weren't so sue-happy, I wouldn't need one!
langford@reed.UUCP (Chris Langford) (10/27/87)
To the person who wanted to reformat disks quickly, I have found that either a big magnet or a bulk audio tape eraser does quite well. Just don't use it too near your oter disks. tektronix!reed!langford
bill@upba.UUCP (11/03/87)
Why don't you try one of the commands that appear under the Special selection on the menu bar. It is called erase disk. Make sure though that the disk you want erase is the newly formatted one. To do so, just make sure that the disk is selected before you select erase disk. Bill Wisell "Works Great. Less Space."