16 Jan
2023
16 Jan
'23
4:47 p.m.
On 1/16/23 02:14, p.gebhardt--- via cctalk wrote:
Hello list,
Yesterday, I was wondering, if there are any multiplatter disk pack production tools
known to exist?
There are disk pack inspection and cleaning tools in the wild (also one on eBay for a
ridiculously high price) and occasionally, I also saw unused and originally packed disk
platters for sale, but these are, to my limited knowledge, worthless if the production and
platter alignment tools are missing.
I remember vaguely somebody writing on this list years ago that some last systems were
tossed by some company in California. But disk packs were also produced on the European
continent and in for instance in Bulgaria(ISOT) for computer disk drives in the federal
republic of Germany and the Soviet Union.
I was just wondering about this since it is getting more and more difficult to come
across disk packs provided that spare unused platters arw available. The (9)877 for the
CDC SMD 80MB drives 9762 and OEMs seemed to have been fairly wide-spread and these still
show up from time to time for offer. But the 300MB packs for the CDC 9766 are rare now.
Older drives are close to unobtainium. I never came across a five-platter pack for my CDC
854 drive and i have never seen packs for my MMD 844 or my CDC BC3xx disk drive for 200MB
disk packs.
The question will rise what I wanna do with these. I have a working 9762 drive and some
day, I would like to try to restore the other ones I have. For the SMD drives, I have
spare heads and alignment tools and a disk pack cleaner. I don't intend to run them
for hours because I don't have a clean room environment that is appropriate to the
specs of these drives. I just love these pieces of storage technology and it would be
great to at least have one pack for the drives that are missing one.
Any thoughts from the disk experts would be greatly appreciated :)
The 844 drives date from the early 70s. I worked for CDC on a military
project where these were brought in to replace the 821s that were bid
(yes, I know there's no information on those--they're essentially a
high-capacity unit build on an 808 chassis and unreliable as hell). A
typical installation might have used over 100 of the units on a 4-CPU
Cyber cluster. They worked well, unless one got a bad pack, which would
clobber the heads on a drive; using the drive on a new pack would result
in creating another head-clobbering pack. I recall an overnight report
issued by an operator where he succeeded in trashing several packs and
multiple drives in his attempt to get something to work. It was a
blow-by-blow report somewhat akin to the Gerard Hoffnung bricklayer story.
Can't tell you more about the mechanics of the things--I haven't seen
one of these in many many years. They were the workhorse drive for CDC
large systems for quite some time. We used them on the STAR-100, for
example.
All the best,
Chuck