Working with Old Tapes

Jeffrey S. Worley technoid6502 at gmail.com
Wed Oct 17 12:51:42 CDT 2018


Probably preaching to the choir, but if you are going to be mounting an
old tape, there are some issues to be aware of.

Tape is really stable over time and your data is likely still there.

As tapes age, the surface of the gluey oxide coating degrades.  The
symptoms will be very discernable with a nine-track drive as you can
see the head/tape interface easily.  The surface of the tape in contact
with the drive's head will ablate, leaving gunk on the head.  The tape
will make a squeaking noise while running and may eventually stop
moving due to sticktion at the head.

Cleaning the head from time to time may get you through a read of a
tape for backup purposes, but there is a machine called a 'tape
cleaner' which is a drive which leads the tape through a path seeded
with knife-edges.  As the tape travels through the machine, the knife
edges scrape a layer of oxide coating from the tape and smooths and
polishes the surface exposed.  This will restore a tape to full
usability and should not affect data stored on the tape.

Pinch rollers can also collect oxide and need cleaning.  Pinch rollers
on old drives may be so degraded as to make the drive unusable.  I had
a Data General cart drive using Qic 300? tapes.  The drive roller was
wrecked.  I found in my junkpile a roller from an Epson Actionprinter
3250, removed it from the printer's output roller and after cleaning
the drive axle in the qic drive, used some windex to lubricate a
ballpoint pen barrel, stretched the roller onto the pen body, held the
body to the face of the drive axel and pushed the roller on.  It worked
beautifully from then on.  Stone knives and bearskins.

You can carefully make a set of knife edges on a board, thread the tape
through the edges, and use the drive you have to move the tape through
your homemade cleaner.

Best,

Jeff 



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