[vcf-midatlantic] Workshop after-action report (IBM 029)
Mike Loewen
mloewen at cpumagic.scol.pa.us
Mon Feb 29 19:23:49 EST 2016
For the 2/27 - 2/28 workshop, I did some more work on the museum's IBM
model 29 keypunch. When I first powered it up, it didn't do much of
anything except run the motor. It gradually "warmed up" and started
punching, but was obviously in need of lubrication. I cleaned and
lubricated many maintenance points, which quieted down the machine and
made its operation much smoother. I used Tech Rubber Roller Restorer to
clean up the rubber feed rollers.
I replaced my home-made arc suppression board with a spare from the
warehouse. I also replaced the punch clutch pulley belt, which was ready
to fall apart, and substituted a much better looking program drum. I
adjusted the two pressure rail microswitches in the card bed, and cleaned
and lubed the keyboard to fix some sticking keys.
During the process, the machine developed another fault: each time a
card would "register" at the punch station, it would automatically be
"released" and sent to the read station. After several hours of
troubleshooting, I discovered a broken wire leading to the escapement
magnet assembly. It had been hanging on by a thread, causing erratic
operation, and eventually completely broke away from the spade lug. I
soldered it back on, and the machine was again punching.
The very last thing I checked was the function of the sensing pins in
the read station, by trying to duplicate a card. Not all card rows were
consistently read, but improved with repetition. Unfortunately, I ran out
of time at that point. I had lubed the sensing pins, but they need
another round of cleaning/lubrication.
At this point, the keypunch is useable for demonstrations in the
museum room. The print mechanism still needs work, and doesn't print
all of the characters correctly. Cleaning and aligning the print
unit will be a major project.
I multi-punched a VCF EAST 2016 card and left it on the punch.
Oh yeah: I also pushed an IBM printer for a 1/4 mile. :-)
Mike Loewen mloewen at cpumagic.scol.pa.us
Old Technology http://q7.neurotica.com/Oldtech/
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