On Jan 16, 2023, at 11:54 AM, Jon Elson via cctalk
<cctalk(a)classiccmp.org> wrote:
On 1/16/23 04:14, 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.
Washington University had a magnetic media lab at one time, and got several semi loads of
gear from an IBM lab. There were air bearing spindle tables and many racks of IBM
circuitry based on MST chip technology. I assume some of this could have been used as
servo track writers. Any system that doesn't have a dedicated servo surface or
embedded servo info doesn't need a servo track writer, it can just format the pack by
itself (with proper diagnostic programs, of course.)
There are a few other odd cases. Fixed head drives might have a timing track; the DEC
RS64 and RF11 do. For those, if you replace the platter you have to rewrite the timing
track, which requires a specialized device. I've seen it done on an RF11 that was
pretty much rebuilt from the base plate upward. The special tools needed -- alignment
disk and timing writer -- had to be sent over from Maynard, they were not standard field
service equipment. The documentation was pretty minimal, but our FS tech was really good
and had no trouble figuring it out. I think it was the first time he did one of these
jobs.
paul