Tom, If you would like some known good disks to test with, I'd be glad to format a few 8 inch disks for you to use as test disks. Just email me and we can figure it out. Chuck sent me a few disks when I was first setting up my 8 inch drives a few years back and that was invaluable. I'd be glad to pass along the favor.
Travis On Wed, Oct 9, 2024 at 1:38 PM Wayne S via cctalk <cctalk@classiccmp.org> wrote: > Tom, make sure to clean the heads of the floppy drive and check the heads > to see if they don’t have any sharp edges, from excessive wear, that could > damage the disk. Also spin it up with a scratch disk to see if it spins > okay. > Check the source disk for mold and dirt and see if it spins smoothly in > the jacket w/o hangup. > > Sent from my iPhone > > > On Oct 9, 2024, at 12:05, Tom Stepleton via cctalk < > cctalk@classiccmp.org> wrote: > > > > Hi folks, > > > > I have a floppy disk data archiving project to undertake, and although > I'm > > aware that this can sometimes lead to spirited discussion (and hope to > > avoid that!), I'm interested in current good practices for pulling data > off > > of hard-to-replace disks. > > > > In this situation, the disks are 8" floppies likely in ordinary IBM > > 26-sector, 77-track, 128-bytes/sector, double-sided FM format. I have a > > flux reader and will have a pair of Shugart 851 drives for the job; these > > likely haven't been used for a while, though. At this stage I'll consider > > the job done if I manage to get good low-level recordings from the disks: > > assuming the FM data decodes well and sector CRCs look good, further > > analysis can come later. > > > > The main risk I'm worried about is physical damage to the media. While > > reportedly the disks don't show visible defects (nb: they belong to > someone > > else so I can't inspect them myself right now), I'm still anxious about > any > > chance I might find the binder that secures the magnetic material to the > > cookie degraded to the point of allowing the oxide to come free. Most > other > > situations I think I can deal with, but I'd like to have a more concrete > > plan if I start to find oxide building up on the heads. > > > > I'd be interested to know what precautions people might take for common > > data recovery problems. One option is cyclomethicone for cleaning and > > lubrication if necessary, but other than "you could use this", I'd be > > interested to know details of how people put it to use if they are > worried > > about media failure. Meanwhile, I'm disinclined to use isopropanol or > other > > more aggressive solvents given received wisdom, although I know opinions > > differ here. > > > > The disks are boot media and other materials relating to the RSRE Flex > > operating system <https://en.wikipedia.org/wiki/Flex_machine> as > developed > > for PERQ workstations. I'm not aware of other copies of this OS being > > available, though it would relieve some of the pressure to learn that > these > > weren't the only ones. The disks themselves are primarily ICL-branded > > although a few indicate manufacture or resale by Maxell, DEC, Inmac, > among > > other brands. > > > > Is there anything else that people would advise me to look out for? > > > > I did find this thread > > <https://classiccmp.org/pipermail/cctalk/2018-July/040673.html>, but > > practices may have advanced in the past six years. I know the whiteboard > > cleaner that folks seem to have liked is difficult to find these days, > > particularly here in Britain. I've also had a hard time finding Photo Flo > > or similar photographic wetting agents and have used deionised water > with a > > drop of dish soap instead. > > > > Thanks for any advice, > > --T >
