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View Full Version : I hate 3.5" HD floppies



geoffm3
February 28th, 2011, 06:17 AM
Who else is with me? In the process of getting my newly acquired IIci running I've run through about half of my old stock of HD floppies (which admittedly isn't many anymore) that had bad sectors on them. I don't recall near this much trouble with DD media as with HD media (and I have a LOT more 3.5" DD stuff than HD). And it's not like they are all that bad a brands for the most part, and some are reformatted distribution media (from the likes of Compaq or Microsoft).

I guess maybe some of the equipment is showing its age, or by the time HD media had come along it was such a widely used and cheap format that quality took a dive.

mark66j
February 28th, 2011, 06:22 AM
I think distribution media is often poorer quality, since to do its original job it only has to be written once. I've found a lot of those disks that won't take a reformatting.

geoffm3
February 28th, 2011, 06:27 AM
I think distribution media is often poorer quality, since to do its original job it only has to be written once. I've found a lot of those disks that won't take a reformatting.

That's a good point. I've got a small stack of floppies at work that I'll take home and try with it. I haven't had a machine here that's needed them for the past 8 years. :)

Chuckster_in_Jax
February 28th, 2011, 06:39 AM
I've had "some" problems with the 3.5" HD diskettes. They're certainly less likely to get damaged than their 5.25 counterparts. At least the 3.5" HD are still readily available and recently manufactured. Almost all of the 5.25 media is 20 years old now.

glitch
February 28th, 2011, 06:39 AM
I hit used media with my TV degaussing ring before formatting them. I've found it reduces the bad disks. But yes, in general I have more 3.5" HD floppies with problems than DD media, and I've probably processed (i.e. formatted, checked for bad sectors, and used) 500 of each in the last 5 years.

geoffm3
February 28th, 2011, 07:11 AM
I hit used media with my TV degaussing ring before formatting them. I've found it reduces the bad disks. But yes, in general I have more 3.5" HD floppies with problems than DD media, and I've probably processed (i.e. formatted, checked for bad sectors, and used) 500 of each in the last 5 years.

The degaussing coil's a good idea. I've got one in my toolchest... might have to give them a whack with that and see if that makes them work better.

Chuck(G)
February 28th, 2011, 09:06 AM
I've vented on this subject many times ever since I bought my first box of Fuji DSHD media for the bargain price of $45--I don't have a single good one left, BTW.

What the DSHD 3.5" media won't withstand, regardless of what you do (including degaussing), is multiple writes. I've still got new boxes of Imation, Sony, Maxell, etc. and they all behave the same way--they'll accept a few write/format passes and then go belly up. On the other hand, I rarely throw out a DS2D 3.5".

My personal opinion is that since the 1.44M media came out after most PCs were sold with hard drives that it was designed as a distribution medium and not a working medium. I'd asked a few folks at the NML when it was in its heyday about this, but never got a satisfactory answer.

geoffm3
February 28th, 2011, 10:34 AM
I've vented on this subject many times ever since I bought my first box of Fuji DSHD media for the bargain price of $45--I don't have a single good one left, BTW.

What the DSHD 3.5" media won't withstand, regardless of what you do (including degaussing), is multiple writes. I've still got new boxes of Imation, Sony, Maxell, etc. and they all behave the same way--they'll accept a few write/format passes and then go belly up. On the other hand, I rarely throw out a DS2D 3.5".

My personal opinion is that since the 1.44M media came out after most PCs were sold with hard drives that it was designed as a distribution medium and not a working medium. I'd asked a few folks at the NML when it was in its heyday about this, but never got a satisfactory answer.

Glad to see I'm not the only one that thinks they're junk. I guess the higher bit rates are a problem for them. You would think that degaussing would take care of the issue if it was stray magnetics. Maybe there's a problem with the binder or what.

Most of the problems I've had with DS2D back in the day were directly attributable to the lameo trackdisk.device and/or OFS on the Amiga I think. They would occasionally give read/write errors on the Amiga, but they were always okay after a reformat. I rarely had problems with them on other machines.

Chuck(G)
February 28th, 2011, 11:23 AM
If it's any comfort, I've found the DSED (2.88M) floppies to be just as unreliable.

gerrydoire
February 28th, 2011, 04:30 PM
Sticking my nose in here,

when i went through boxes of old 3.5 1.44 meg floppies that were over 15 years old, 99.99% of them were dead, that is, one's written to by me, that being said, when I went through old 360k and some 1.2 meg floppies, the number of them dead written by me, was substainly less.

I had fewer errors reading commercial 1.44 meg floppies.

Cheers!

k2x4b524[
April 5th, 2011, 01:43 PM
If it's any comfort, I've found the DSED (2.88M) floppies to be just as unreliable.

great, i've got 40 of those and 2 mitsubishi 2.88mb drives.. too bad the controller chips, though they support them are anal about it..

NeXT
April 5th, 2011, 05:53 PM
They seem to have a shelf life for me.
I generally keep a large quantity of preformatted floppies I preocessed three years ago and rooted out any of the bad ones.
I had to make some disk images the other day suing a few of these disks and reformatted them again and to make eight imaged disks, I had to chew through twelve disks.

Tor
April 5th, 2011, 10:57 PM
I'm in the process of reading old media and so far (I'm still collecting statistics) the 3.5" media is by far the worst. I had suprisingly little trouble with 1.2MB 5 1/4" floppy disks, some at least 24 years old. Out of a collection of dozens there was one or two which needed a second read before reading OK, and two which I can't read at all. Those two are very strange and part of the same set so there may be something else going on. Everything else read perfectly.

I'm also now reading my old 9-track CCT tapes (after finally finding my old CCT drive again), and those tapes are also surprisingly good. There are a small percentage with problems, but most of them are fine. These are also up to 25 years old.

3.5".. so far, that's been a disaster. There's hardly any floppy recoverable at all. Most of them are newer than my 5 1/4" floppies, but that doesn't help - just can't read them. DD is even worse than HD, but that could simply be because they're generally older than HD. So far (I haven't gone through all of them, and not tried too many floppy drives either) it looks like stuff stored on 3.5" is the same as lost data.

The whole collection has been stored under exactly the same conditions all these years.

deathshadow
April 6th, 2011, 07:00 AM
3.5" floppies sucked when they were a new technology, and if real read/write data on hard drives wasn't the norm by the time they were commonplace, I don't think they'd ever have been adopted for widespread use.

20 years ago I had a 50% reject rate on 3.5" disks after 3 to 6 months of use and a 1 in 30 reject rate out of box... That's back when it was a mainstream supported technology. It was laughably pathetic how unreliable they were compared to 5.25", despite the 'more durable casing'. Admittedly that casing came with one of the worst engineernig disasters in computer technology, the metal slide-door... I lost count of how many times I had to take an entire computer apart JUST because the damned door came off INSIDE THE DRIVE. I had a co-worker who got so torqued off about it, he went around and ripped the doors off every single floppy and hand-made their own paper sleeves for them.

It's far worse today, where I open up a "new" box and it's a 2 in 10 reject rate, with 9 out of 10 being dead after two to three months. About 1 in ten of them make a slight grinding noise when inserted into any drive... doesn't matter if it's old stock I've built up here or who I get them from.

While pretty much every 5.25" disk I have dating back to 1978 still works like new. I don't know if it's the denser packed sectors, I don't know if it's an engineering issue relating to the metal spindle and metal door, or if they're just cheaper media...

...but 3.5" disks have ALWAYS sucked, and it's just gotten worse over time.

Chuck(G)
April 6th, 2011, 07:19 AM
Curiously, from my samples, 3" floppies don't appear to have the same problem. Of course, they're recorded at DD, not HD rates.

barythrin
April 6th, 2011, 07:53 AM
Any idea on what actually causes this? Is the magnetic layer on the floppy deteriorating? I've heard of things like disc rot and some bacteria that eats CDs but I'm not sure if that could apply to floppies. I know some times there were calibration issues with floppy drives that could end up writing data sort of off track which the system at fault would read fine but others might not. Same with laser strength.

Was just curious if anyone played much with recovering the data such as the dish soap cleaning method, etc.

Chuck(G)
April 6th, 2011, 09:11 AM
It's an interesting question and one with which I've played around for a time. One of these days, I'll have to write it up.

Like most of you, I've got lots of failed DSHD 3" floppies. Almost always, they began failing after just a couple of uses. What's even more perplexing is that I can take a perfectly readable floppy and attempt to reformat it--and the attempt will fail. Degaussing (and I've got the mother of all degaussers) doesn't help.

If what we were looking at was a simple instability in the coating, then one would expect the innermost cylinders to fail first, as they're most sensitive to failures (recall that the induced energy in the drive read head is proportional to the square of the linear velocity of the media).

But that's not the case.

Take a failed floppy and format it "blind" using Anadisk's FORMAT feature, then go back and take a look at things. If your experiences are like mine, you'll see that the failures tend to be on the outermost (i.e. most reliable, theoretically) and occur in"patches" closest to the index. A look with a diagnostic fluid such as Kyread shows that some areas aren't being magnetized at all.

My own unverified theory is that the coating actually suffers some sort of mechanical damage at the particle level when written. Since outer cylinders are being rewritten more frequently than inner ones, the problems begin to manifest themselves more readily on the outer cylinders.

HD tends to manifest this more readily than 2D, simply because the coating is less heavily "loaded" (i.e. the ratio of binder to particles is greater) and the coating on a HD floppy is only about half as thick as that on a 2D.

Again, this is a lot of back-of-the-envelope speculation, but perhaps there's something to it.

Unknown_K
April 6th, 2011, 02:16 PM
The most unreliable disks are 3.5" HD with the 1.76MB (or whatever MS uses) extended formatting. I have quite a few 3.5" HD disks I wrote on over a decade ago that still work. The most reliable disks seem to be 5.25" of any variety. Commercialy formatted disks seem to be very good, never had a C64 floppy fail on em yet and those are closing in on 25 years old.

Bungo Pony
April 9th, 2011, 04:38 AM
I absolutely dreaded the 3.5" 1.44M floppies. A few writes to a brand new one and it goes bad and straight into the trash. I don't even think about trying to recover the data off them. The only thing I've noticed is differences in the floppy drives. One may not read it, but another might. If there's something absolutely needed off that floppy, try that before tossing it.

Toward the end of my 1.44M floppy usage, I found that if you even dropped the damned thing, the data seemingly jumped off it, shattered all over the floor, and the floppy became unreadable. People in high school thought I was bizarre for being the only one to use a 5.25" floppy in my computer class (back when computers still had the drives) rather than using a 3.5" floppy. I still have that floppy from my computer class, and it's still 100% readable. I'll bet everyone else's floppies from that class have been long since junked.