Precision Horology
Precision Horology


There were a number of ideas I had which I wanted to incorporate in this clock. It should be seconds beating utilizing a pendulum and bobs that were of a material that had a minimum coefficient of expansion so as to minimize temperature related problems. The pendulum must be as free as possible to minimize the effect of pendulum “work”. It should run in a vacuum to eliminate barometric effects and to increase Q. I wanted to minimize the effects of  suspension wear (in the case of knife edges). I felt impulsing the pendulum in both directions was important and  utilizing magnetic

impulsing and sensing seemed like a practical method to use in the design because I could more easily control them. Apart from the practical considerations, I wanted the clock to have an attractive, functional look.

How the clock was to be mounted was also an important consideration. I wanted to keep the clock in my workshop. It was important to isolate the clock mounting as much as possible so that walking around the shop or running a machine would only have a minimal effect. When I had the concrete foundation/floor poured for the shop, I had two large 4 cubic foot "wells" built into the floor into which I fitted 2 blocks of specially reinforced concrete. Each block weighed about 1 1/2 tons and rested (or floated) on a set of isolating dampers so the block was physically isolated from vibrations in the room - and every else for that matter. Then I had two stanchions fabricated, one for each block. The stanchions were mounted to the concrete blocks and the bracket for Q1 was affixed to one of the stanchions. Having run this clock for quite a few years now, I can see that although the isolation blocks work fine with

Clock Q1 with its associated electronics

regard to the usual vibrations from the road and my shop, it does not isolate the clocks from very slow wave vibrations(2 or 3 hertz) from distant strong earthquakes. The effects from certain earthquakes can be seen in the clock record.

It took me about a year and a half to complete the clock in my spare time.


Finished clock Q1

Clock Q1 in the test stand

Q1 shown mounted on its stanchion with its electronics and the computer used to measure rate with a MicroSet Timer

Q1 experimental dial movement↓

Q1 in the test stand with an experimental invar top bob.→

Click here to see a video of Q1