• LCrawford (unregistered)

    I've never seen a floppy disk used so much that it wears out.

  • MrBadger (unregistered)

    Nor me. I will file this story under the 'bollocks' category.

  • Derp (unregistered)

    Gern fantasy, didn't read.

  • martijntje (unregistered)

    TRWTF is this story, it's so ridiculous nobody will believe it.

  • Link8312 (google)

    Plus, the directory/FAT/whatever is read on every file opening.

    Addendum 2017-07-10 07:24: An individual file is peanuts next to that.

  • Whoever (unregistered)

    I never had think much about this story.

  • Ferdinand (unregistered) in reply to LCrawford

    Been there - done that. As a student project I tried (and eventuelly succeeded) to modify standard "Shugart" 3,5" drives to behave like classical Apple Disk ][ 140KB drives. 10 years ago, this was a fun project and 100% useless. After writing test patterns and reading them back over and over, building a custom read amp in the process (the original 1,44MB read amp was unable to read the low-rate data reliably) I noticed the error rate going up and the signal level going down... Since there was no head stepper motor driver yet, all tests were run on track 0. After (manually) moving the head to a different track things went back to normal. The detoriation was clearly visible as a brighter circle. With the final design, that disk could still be read on track 0, but I decided to discard it anyway. I expect that running the drive until no data could be read and beyond (trying to recover the data) could render a track "blank", but it should take a lot of time. Maybe 8" disks wear out faster. The time reading the directory is very short <1sec, it would need a very high number of accesses to kill it - 20 hours of directory access gets you in the range of 100000 accesses.

  • Wank (unregistered)

    Well since Rubbing Off is a nice Euphemism for Wank, which this story is a load of, I think the title is apt.

  • Bill (unregistered)

    Unless the school held on to the Altairs longer than most, it is a bit after the time of this story, but one of the first double sided 8 inch drives on the market had a head alignment problem that would wear through the coating in a very short time. Double sided drives have a head on each side where single sided had a felt pad on the side opposite the head. It tool a while to get this right. I don't remember the make of the drives, but they were half high 8 inch and used by Cromemco in their CPM systems sold around 1980.

  • Borf (unregistered)

    So, am I reading that sentence wrong, or did Micah write his philosophy thesis in BASIC?

  • Jerepp (unregistered) in reply to Borf

    Possibly he wrote his own word processor first with an early version of autosave... after each key stroke the program writes the file to disk and then reloads the file again to confirm it saved correctly.

  • Goober (unregistered) in reply to LCrawford

    If there's physical contact between the head and the medium, the hardware is defective or broken. Not the user's fault, except to the extent of not learning from the first thousand times they get a read error.

  • Albert (unregistered)

    I saw a 8" boot floppy for a DEC PDP-11with a transparent ring.

    The machine in question was in a forestry research station at the end of some long power lines across Ontario's Algonquin park. Algonquin is a wilderness[1] park with only a few power line cuttings across it, and this particular one seemed to have a lot of trees lying in wait for strong winds to topple them onto the power lines.

    That particular transparent ring was supposedly caused by one branch on a tree that did not fall completely; it made intermittent contact for a few hours. So the PDP would attempt to restart from the floppy again and again and again and....

    When I worked there in 1989 they had much better power conditioning and enough experience to shut everything down at the first power bump. UPS's for that size of a data centre were not a thing that the Canadian National Forestry Service was doing at that point.

    That research centre is now strictly a lot of trees and research plots operation now. There are no offices or data centres or biology labs on the property anymore.

  • operagost (unregistered) in reply to Goober

    Goober, floppy disk drives actually make physical contact with the medium, like magnetic tape, and unlike hard disks.

  • Albert (unregistered) in reply to Goober

    I agree that hard discs with head contact are broken.

    Floppy disks are a different story.

    The flexible disc material and the low-ish rotation speeds it can tolerate (remember that the 8" and 5 1/4" discs had the stationary sleeve constantly in contact with the rotating magnetic disc material) meant that the flooding sled heads of hard discs could not be used. Direct low speed contact was the only way to assure the close offset needed for the magnetic operations.

    Floppy discs are consumables, and folks who obsessively save and re-read from them (maybe for protection from power outages :) ) should work out a schedule to rotate them. Now only this who deal with tape backups have to deal with this regularly.

  • t0pC0der (unregistered) in reply to Derp

    Why do we have these fantasy novellas here? First it's that samurai nonsense, now fluff like this. It's not funny, it's not entertaining, just a waste of bandwidth

  • Klimax (unregistered) in reply to t0pC0der

    You could go as an example and stop wasting bandwidth by wrong posts...

  • Herby (unregistered)

    Yes, floppies ARE contact magnetic media (reel to reel tape is another). The head on one sides floppies (originals) was contacted with the disk by a rubber pad on the other side of the disk pressing the "floppy" into the head. If designed correctly, the head was lifted after a couple of revolutions of the disk if not in use. On early 8 inch drives (like the ones at the beginning of the story), the head lifter was a strange rail that when the solenoid was activated, it would take the head pusher (on the other side) away from the disk. Some designs of floppy controllers (some of this was before single chip controllers) could do just about anything in weird states (like when reset was activated at a strange time). In addition, the 8 inch drives had AC motors that spun the disk ALL THE TIME. This if not treated correctly (and with user inexperience) is a recipe for disaster. Thankfully few machines have floppies, and those that do, have head lift timeouts that are quite reasonable, as well as motor controls to stop the spinning. Thankfully most media now (flash thumb drives) has a bit more endurance.

  • Lerch 98 (unregistered)

    Not fantasy, but quite possible if the drives and disks are dirty and dusty. Floppy drives needed to be cleaned. there was a special disk that you inserted into the drive and it would clean up the head. I never saw a disk that was worn though to become transparent, I think this is an embellishment, but I have seen rings on the disks. And it is true, the disks do wear out. This is usually prefixed by getting read errors. This is why we always had backup and backups of back up. You would make a copy of the original and use the copied disk, IF and when it got goofy it was time to make a new copy from the original.

  • TheCPUWizard (unregistered)

    "The earliest floppy disks and hard drives used an iron (III) oxide surface coating a plastic film or disk." -- "Hard" disk were metal platters (often aluminum), the usage of flexible plastic was the definition of "Floppy".

  • Laurie R (unregistered) in reply to LCrawford

    I have seen a diskette worn through. Our office had a diskette-based DOS PC do download stats from a PBX (private telephone exchange) to the server because it needed a security dongle that only worked on really ancient kit. It ran for years until eventually failing with "Invalid COMMAND.COM".

    DOS had to reload the transient part of COMMAND.COM whenever it was overwritten in RAM (which was every minute as the collector ran) and eventually that file location on the DOS diskette wore out.

  • Karl Bielefeldt (github)

    I worked in school computer labs through college. I can attest that floppy disks were indeed designed to wear out precisely when term papers are due. Students had 50MB of free cloud storage, and certain majors like CS could get upgraded to 100MB, which was a lot back then, but almost nobody trusted it. They wanted to hold the file in their hands.

  • Steve (unregistered) in reply to LCrawford

    I have, but NOT to where it was transparent! I HAVE known people that CRASHED REAL COMPUTERS with programs that worked in a similar way, loading up a HUGE array, processing one item, and then wiping it out and loading up a HUGE array again. That would be bad enough, but processing 100s of thousands of rows for ONE data record is incredible! And then clearing ALL is also bad.

  • Pawsanias (unregistered) in reply to Borf

    Obviously he should have used an object-oriented language to self->know()

  • castlerobber (unregistered)

    "Micah explained. He had written his code to read the data file, find the lowest value, write it to an entirely new file, then mark the value in the original file as read. Then it would read the original file again, write another new file, and so on."

    Years ago, a former (for good reason) co-worker of mine was given the task of moving blank elements to the end of a 10-element list. He didn't even have to sort the non-blank elements. This was his "brillant" solution, copied verbatim:

    X = 0;
    DOU X = 99;
    X = X + 1;
    IF X < 10;
    IF TmpEndo(X) = ' ' and TmpEndo(X+1) <> ' ';
    TmpEndo(X) = TmpEndo(X+1);
    TmpEndo(X+1) = ' ';
    X = 0;
    EndIf;
    Else;
    X = 99;
    EndIF;
    Enddo;

    tl;dr: Every time he swapped a blank element with a non-blank one, he went back to the beginning of the array and started over.

  • markm (unregistered) in reply to Goober

    That's true for hard drives, although I don't believe application software has much to do with how high the heads ride - that's either set in hardware, or it's in the firmware embedded in the drive. With floppies, the heads do ride in physical contact with the disk. The speed is too low for the Bernoulli effect to maintain a constant head gap, and the surface is flexible, so the only way to get a consistent head gap is to press the disk against the head for zero gap. (There may be a non-magnetic shoe or coating on the head that holds the magnetic coil at the desired distance.)

    Usually there's a felt pad on the back side of the flexible disk to maintain pressure against the head. For two-sided disks, this requires offsetting the heads and the slots in the disk envelope. One of the earlier posters suggested that this 8" drive model had the heads directly opposed, so instead of the felt pad backing, each head was the backing for the other one. The head materials are of course much harder than felt, so I'd think that even though the heads are on springs, the pinching force on the disk will be more variable and reach higher peaks than with the felt backing.

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