100 webcam tubes
I'm wondering about energy harvesting from the bell flies to charge up a battery..., When I tap it I tap the shaft horizontally back and forth the 0.5mm a couple of times. When I first put it in about a year ago (look at diary comments April to June 2015) it seemed to make a difference. A contact area of 20mm^2 leads to stress of 50MPa so the "knife edges" would be quite thick.
I suspect the 19c clock makers would have done it this way if it was a better solution.
Watch the clock strike twelve or hear it strike twelve at Singing from the Towers . Today's and yesterday's weather in Cambridge, including wind.
Here is a graph for the last 30 days of drift A barometric compensator was installed at clock change - midnight 28 March 2010.
This is why I'm thinking that a gradual rate of change of temperature (over days) can cause tower tilt.
The clock itself is an engineering marvel, accurate to better than 1 second per month.
Had to do a hard (push the button for 5 seconds) reboot.
Then up came a nasty black windo saying "file system errors" ...
In fact from this it is possible to decuce direction of tower tilt, and it's consistent with warming on the sunny side. Thermal diffusivity is a useful parameter to describe heat flow through the stone walls. This means that a step change in temperature will take 1 second to reach a depth of 1mm, and 3 days to penetrate half a metre.And there's not much point in going to the trouble (and it would be a lot of work) if there's no intention of using it.The barometric compensator is fine because it can be removed in under 5 minutes and the clock is back to its original state. The only thing I don't like about the vibrator idea is that it needs a battery power supply. And for mods like knife edges, etc, they'd have to support the 100kg weight of pendulum.One theory is that the minute and hour hands interfere with each other as they pass, but these photos [link] [link] taken at 8.44am a few weeks later seem to show that it's OK tapping rather more vigorously. Maybe dislodged a sticking zinc tube in the pendulum, after all my insistence that it wasn't sticking. It's zoomed into 2 hours 5-7pm GMT Note a tapping at about caused a step drop in amplitude but a step rise in drift. Then a more vigorous tapping at caused a drop in amplitude but a step change in going. Then a few minutes later, I don't think I did anything...!changing the suspension would count, in my view, as irreversible, because if it works then who would want to put back the old one?