then all the way up the wheel train to the mainspring. I
always think of the lowly hairspring as the "heartbeat" of a
watch or clock. Similarly, when the hairspring gets
magnetized, it is so small that the wildly changing N-S poles
of the magnetic charge cause the poor thing to wind /
unwind out of control, resulting in erratic timekeeping. Your
fix, however, sounds much more elegant than mine.
Finally, whenever I have a watch / clock question, I
always reach for the "bible:" Handbook for Watch & Clock
Repair by H.G. Harris, 1961; Emerson Books. It's long been
out of print, but this book is a valuable reference and worth
looking for. The assembly illustrations alone are worth it.
Excellent explanation — and reference suggestion. My
latest adventure is rebuilding ATMOS clocks. Much simpler
than rebuilding watches, but not necessarily easier. I've
discovered there's a practical reason for the glass case. The
slightest disturbance and it stops. So, no bookshelf clock. I
don't have a fireplace, but I found a nice stable countertop.
Works great there.
The Magic of Magnetism
Your November editorial on magnetism really stuck
(pun intended). It reminded me that we don't think as much
about magnetism today than we did years ago. We may
even overlook that without magnetism, there would be no
useful electricity. Wasn't magnetism one of the magic things
that inspired us as kids? Who didn't wind a coil of wire
around a nail and connect a battery? Who didn't play with
iron filings and a magnet? Who didn't ponder why our nail
electromagnet was eating up our batteries?
We find magnetism in motors and generators. They are
in speakers, microphones, phonograph pick-ups, tape heads,
Then, there are the moments when your experience
with magnetism saves the day. In the early 1990s, my friend
bought an expensive Sony Trinitron CRT display for his
computer. It was supposed to be the best of its day. He
called me complaining that there was a problem with the
screen image at the top right of the screen. It was wiggling
ever so slightly. I asked him if he had any florescent lights
near the monitor. No. Any other electronic device nearby?
No. Just the old analog electric alarm clock on the shelf
above the monitor. He moved the clock and the display was
fine. Those old shaded pole clock motors were notorious for
belting out a strong magnetic field!
Years later, I was in a "dollar store" checkout line. The
cash register had a small green monochrome CRT screen
and the display image was shaking wildly. It was
summertime and the clerk had a personal fan near the
register. I told him if he moved his fan the display would
stop shaking. Another shaded-pole motor. He thought I was
No story-telling would be complete without mentioning
demagnetism. A friend's child applied a powerful magnet to
the front of their new computer CRT monitor. Of course, we
know that creates severe color purity problems. Even the
built-in degaussing was not helpful. The store told them they
needed a new monitor. I went to their house with one of
those big bulk tape demagnetizers. I started rotating the
energized demagnetizer in the center of the screen and
gradually worked my way away from the screen before
turning off the power. Good as
new! Just like high voltage is
useful but undesired when it
is in the wrong place at the
wrong time, magnetism can
be a good friend and a
frustrating enemy. Oh, and
be careful of those powerful
magnets used in hard drives.
They are so strong they can
pinch your skin and draw
Wow, you've had quite
an experience with incidental
magnetism. My latest "gripe"
or perhaps annoyance is an
expensive watch winder that I
picked up online. The
specification didn't mention
that the door was secured by
magnets! Who in their right
mind would put super
magnets within inches of a
mechanical watch for days at
a time? Thanks for sharing.
READER FEEDBACK Continued from page 6
64 March 2016
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