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Chuck(G)
September 5th, 2011, 06:48 PM
I've got boxes of old 3.5" and 5.25" floppies, mostly returns and old stock from the days when we were shipping a lot of stuff on floppy. I will probably never buy another floppy as long as I live.

At any rate, I thought I'd see how the stuff survived, so I picked up a box that was filled between 1996 and 1998, right about when we quit using 720K floppies and moved to 1.44M. All were written and verified to be perfectly good when they were first written.

I decided to use the same machine that wrote them (an old 16MHz 386 tower with 6, count 'em 5, floppy drives on three controllers, so I could process 3 disks simultaneously and have all 6 drives loaded with media ready to go.

I cleaned the drive heads and degaussed a bunch of old floppies, wiped the labels with pain thinner and removed them. My test for 720K and 1.44M media was to keep going on each type until I got 10 disks that verified 100%. The results were interesting.

For the 1.44M floppies, a batch of 10 good ones required formatting 17 old ones.
For the 720K floppies, a batch of 10 good ones required formatting 14 old ones.

Only 2 (combined) exhibited errors on the first cylinder; most of the failed 720Ks were in the last 5 cylinders or so; the 1.44M ones started picking up errors about 2/3rds of the way toward the center.

For the bulk of the media,the brand was Sony, purchased as bulk "duplicator grade" boxes of 500. I think there are some KAO 720Ks from an earlier purchase.

What sets these apart from media purchased within the last 5 years is that the newer stuff after a couple of passes, never gets past cylinder 0 on a format.

Take from this what you will, but maybe recycling old stock isn't such a bad idea.

Unknown_K
September 5th, 2011, 07:15 PM
Newer stuff was never made to "duplicator grade" standards since companies had moved on to CDROM by then. Some of the bulk disks I have purchased were from duplicators dumping old stocks, they all seem to hold up well (bulk packed 3.5" DD and 5.25" DD disks). The retail 10 pack boxes do have a few bad ones here and there (3.5" HD).

Years ago I got a box of Amiga floppies in and some blanks, one of the 10 packs of 720K blanks had each disk inside sealed individually with cellophane which I figured was kind of overkill, hate to use them.

3.5" DD disks are getting hard to find, so you may not have an alternative other then reusing old disks.

What software is on those bulk disks you have out of curiosity?

Great Hierophant
September 5th, 2011, 07:35 PM
The first thing I take from this post is that some disks are so damaged that they are beyond recovery. Even though the disk may seem okay from a visual inspection, show no obvious signs of damage and get passed through a degaussing which should reset it, some portion of the surface may not be able to hold the flux transitions reliably.

For verification, did you perform a full write test or just a complete format with no bad sectors or errors reported?

I would guess that I should not reformat those IBM preformatted Imation 1.44MB floppies I bought new this year too often.

I thought "track" was the proper nomenclature for floppies and "cylinder" for hard drives, although the two terms are synonymous when discussing disk geometry.

Chuck(G)
September 5th, 2011, 08:35 PM
"Track"and "cylinder" are synonymous only if the drive (hard or floppy) is single-sided or if you're talking about the physical position of the head assembly..

A 1.44M floppy is compose of 160 tracks, but 80 cylinders. You can talk about a track as being the physical position of the head assembly, but when you talk about the data accessible at that position, it's a cylinder. At least, that's the way I've been using the terms since my first 1311.

No chance at a full multi-pattern read/write test; just a single pass of format, write and read-verify with no retries.

As far as what was on the disks, let's just say forensics software.

DOS lives on!!
September 6th, 2011, 03:28 AM
What sets these apart from media purchased within the last 5 years is that the newer stuff after a couple of passes, never gets past cylinder 0 on a format.

Take from this what you will, but maybe recycling old stock isn't such a bad idea.
Everything's being made much cheaper these days. They just don't make anything with sturdy metal anymore, just hunks of cheapo plastic.