4/19/2026 at 11:43:15 AM
In all these nostalgic retrospectives, I never read how the zip drive can achieve 100x or more capacity than the floppy. What is the engineering feat that allowed this? There's one paragraph in Wikipedia that says the heads fly across the disk like a hard drive. OK, how did they manage that while the disk isn't sealed? Is that all it took?Similarly, articles just gloss right over the "click of death" without any technical explanation of what goes wrong. Why were these drives and/or media so prone to failure?
There's nothing new in this article.
by iamtedd
4/19/2026 at 11:57:15 AM
> I never read how the zip drive can achieve 100x or more capacity than the floppy. What is the engineering feat that allowed this?Improvement in production processes and materials (e.g. magnetic coatings) allowing smaller tracks and smaller more precisely positioned heads. The 3 1/2 floppy dates back to 1983, the high-density 1.44MB to 1986, the Zip drive was released in 1994.
A “super high density” 20 MB floppy had already been attempted in 1990, and the LS-120, which had the exact same dimensions as a 3.5” floppy (and could read those), launched in 1996, so it was not really exceptional at 6 doubling in 8 years from the 1.44MB floppy.
Also it was expensive, part of that was the lower scale and lack of competition but the increased production requirements were also a factor, Zip drives and media had tighter tolerances.
The click of death was because when the head got misaligned the drive would return it to the home position, if part of the drive had failed the head would never realign so the drive would keep trying, producing a characteristic clicking sound. HDDs can develop the same, but it’s less common than it was on Zip drives. The tighter tolerance were most likely a factor, it was more likely for a zip to age out of tolerance and develop terminal misalignment.
by masklinn
4/19/2026 at 2:15:24 PM
> Improvement in production processes and materials (e.g. magnetic coatings) allowing smaller tracksImprovements in coatings improve the data per track, but no improvement was needed for increasing the amount of tracks. On a 1.44MB drive there are 100 000 bits per track, but only 80 tracks per side. Or, in other terms, the length of a single bit along the track (on the innermost track) was ~1.2µm, and the width of that same bit, sideways to the track, was ~200µm, for an aspect ratio of 166:1. As far as the media was concerned, roughly 10:1 aspect ratio would have been more than enough, or a normal 1.44MB floppy could have supported more than a 1000 tracks per side.
The limiting factor was that old floppies had no way for the head to follow the track, it was just indexed into a fixed position by the drive mechanism. This meant that the tracks had to be ridiculously wide to support all the possible misalignment on both the reader and the writer. To improve track density, what was needed was some mechanism to make the head locate the tracks and follow them as the disk rotated under them. Iomega solved this by etching shallow concentric circles for the tracks on the surface of the disc. These rings were essentially invisible for the magnetic head, but allowed a separate laser to pick the up and follow them.
by Tuna-Fish
4/19/2026 at 10:30:36 PM
The real click of death was when this was due to a catastrophic failure - say, one of the heads had become completely dislodged and was suddenly hanging loose. Then, every single cartridge you inserted into such a drive would be damaged. If you then took that cartridge and inserted it into a fully working drive, it had a good chance of subsequently destroying that drive.Steve Gibson has a good site with historical information from the time when these drives were still marketed and sold: https://www.grc.com/tip/codfaq1.htm
by LocalH
4/19/2026 at 12:17:24 PM
Zip disks were much less floppy than floppies. They felt more similar to a single magnetic hard disk platen. Presumably the stiffness was what enabled the head to float above the medium, while also allowing tighter read/write timing because it wasn't subject to such variation. Having a single manufacturer of the disks (at least initially) probably also helped.by wzdd
4/19/2026 at 11:59:37 AM
IIRC there's some kind of optical tracking going on.by aggakake
4/19/2026 at 12:37:09 PM
https://en.wikipedia.org/wiki/FlopticalA related technology with a name that already answers your question.
by gugagore
4/19/2026 at 1:18:59 PM
The real question is why were 1.44mb 3 1/2" floppy drives used for so long when they were totally obsolete by 1990. I would love to read a more coherent and unified history; my understanding is that there were tons of competing higher-capacity 3 1/2" drives between ~1985 and 1995, but software developers were stuck releasing on 1.44mb because that was the only format which worked reliably across manufacturers. By the time Zip drive came out, software was distributed on CD and higher-capacity floppies were really only used for (geographically) local data transfer.Wikipedia says there was a serious attempt to standardize a 20mb floppy in 1990 which fell apart: https://en.wikipedia.org/wiki/Floppy_disk#High-capacity It's really not the case that Zip made some great leap forward; 15 years of technology's steady march didn't fully trickle down to consumer hardware because of compatibility issues between competing manufacturers.
by LeCompteSftware
4/19/2026 at 4:22:47 PM
3.5 inch already peaked in 1985, thats when NEC first shipped 1.44MB inside PC-8801 mkII MR. IBM followed two years later switching PS/2 to HD floppies, Apple in 1988. 80 tracks ~50KB/s speed. In 1990 IBM bumped PS/2 to 2.88 ED. Different magnetic material, double the bitrate, ~100KB/s.... But NEC beat IBM by already doing 'five blades' in 1988 selling PC-88 VA3 with 'Triple' or '2TD' format 3.5" floppy sporting 13MB unformatted 9MB formatted capacity. Same perpendicular head as ED, same magnetic medium, same bitrate, 3 times more tracks (240) while still using cheap stepper motor unlike ZIP head actuators, compatible with same standard ED floppy controller chips. Sadly no one in the west adopted it :(((
There was one more avenue for bumping capacity never really explored on PC - zone bit recording invented by Chuck Peddle in 1961 and supported by Floppy controllers in Macintoshes, Commodore (Chuck Peddle designed drives) and Victor 9000 (Chuck Peddle designed whole computer). Free 50% capacity bump. Victor 9000 pulled 1.2MB capacity out of Double Density 80 track 5 1/4 drive.
Combine 2TD wiht ZBR and we could have had cheap 13.5MB formatted capacity floppies since 1988.
by rasz
4/19/2026 at 5:13:05 PM
That's kind of the point of my comment - software developers couldn't release on NEC without excluding IBM customers etc etc. They were stuck with 1.44MB because that was the only thing guaranteed to work. There was a human management problem around agreeing on a specification; drive manufacturers and software companies simply had conflicting incentives, so the market was a mess.In retrospect I think the only reason Zip was able to become the undisputed market leader in high-capacity disks is that CD-ROM fully took over commercial software distribution.
by LeCompteSftware
4/20/2026 at 5:48:57 AM
>software developers couldn't release on NEC without excluding IBM customersOh they could and they did in Japan when those computers were sold. PC-88 is not IBM PC compatible.
by rasz
4/19/2026 at 4:54:22 PM
> There's nothing new in this article.An article about an old and long abandoned technology naturally contains nothing new. What did you expect?
by classified