[time-nuts] Casio Watches 13 Year Drift in Seattle

Chuck Harris cfharris at erols.com
Mon Jun 29 15:16:05 EDT 2015

Back in the day when mechanical escapement pocket watches, and wrist
watches were state of the art, the jeweler would adjust the watch to
run at a normal rate, and give them a daily wind.  Everything looked
nice in the display case.

When a customer bought a watch, the jeweler would set the watch to
his shop clock, and instruct the customer to wear, and wind the watch
normally for two weeks, but do not set it.  At the end of the two
weeks, bring the watch back to the shop for a check up...

When the watch came back, the jeweler would calculate the number of days
the watch had been worn, note the difference from his shop clock, and
calculate the daily rate of the watch.  He would then set his timing
machine for the the inverse of that rate, and set the watch to match.

Now, when the customer wore his watch, the watch would seem to always
be right on because it was adjusted for a rate that compensated for
the customer's patterns of wearing the watch...his "personal error".

This trick had an added advantage because the customer got to see
how so-so his brand new watch behaved during those two weeks, and
got to be dazzled by his jeweler's rare ability to make the new
watch perform so much better than the factory could!

If this was normal back at the turn of the 20th century, why wouldn't
Casio, and others at least do as well?  Especially now that all
electronic watches have a microprocessor built in... complete with
temperature sensing diodes, battery monitors, and other nifty gadgets.

-Chuck Harris

Bryan _ wrote:
> But wouldn't normal watch wear just balance itself over time, one wears their
> watch for say 12 hours and the rest it sits on a counter at a much colder
> temperature. So wonder if Casio would actually go to such lengths to compensate.
> Maybe, interesting though.
> -=Bryan=-

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