[comp.sys.mac] More SE Floppy Problems

strub@sdics.ucsd.EDU (Hank Strub) (11/24/87)

I too have experienced misc. destroyed floppy directories on my
within-warranty dual-floppy SE, although it seems to happen only for
the upper drive.  I had guessed that the problem was due to the drive
being slightly misaligned with the slot, a problem I had remembered
hearing about on Pluses.  I was resolved to get my machine 100% right.

After a week (and the bookstore PROMISED only 2-3 days), I've been
told that both drives passed all diagnostics, and that there is no
way to tell that a drive is slightly misaligned unless it fails
the diagnostics.

Has anyone actually found the source of this very intermittent
problem?  Is there a way to check floppy drive alignment with
the drive's slot?

				Thanks in advance for any suggestions,

				Hank Strub
				UCSD, Institute for Cognitive Science

strub@nprdc.arpa OR strub%sdics@sdcsvax.ucsd.edu OR
. . .!sdcsvax!sdics!strub

cm450s02@uhccux.UUCP (11/25/87)

In article <415@sdics.ucsd.EDU> strub@sdics.ucsd.EDU (Hank Strub) writes:
>
>Has anyone actually found the source of this very intermittent
>problem?  Is there a way to check floppy drive alignment with
>the drive's slot?
>
I assume you're talking about the physical alignment of the floppy
drive opening with the drive itself. If so, the only problem I've
even had with my Mac Plus in this respect was that floppies tended
to get jammed a lot. They'd eject only halfway, so I'd have to either
use the paper clip approach, or else push the disk back in and try 
ejecting it again. A closer look revealed that the floppy disk was
actually scraping the edges of the slot as it was being ejected.
As it turned out, the drive mounting bracket was warped from the time
I dropped the Mac on the floor. The floppy drive's heads had been 
smacked together in the same accident, and the drive began eating 
large numbers of disks. The heads must have either been cracked or
scratched, because a close look at some of the damaged disks
revealed many very fine scratches in the disk surface, which were
not there previously. Generally, these disks could not even be 
reformatted. I've since gone on to a Mac II, and most of these 
problems have gone away, though I consistantly seem to have problems
with Dysan floppies. No matter who's machine I'm using, they seem to
lose sectors from time to time. The only other problems occur with
floppies containing frequently updated files, such as word processor
documents. In these cases, it's mostly a case of the files becoming so
fragmented as to be unreadable.