Clock Time Regulation for iPhone

ClockMaster is an app dedicated to the measurement and regulation of mechanical pendulum clocks. The app uses a compatible vibration pick-up or microphone to capture the audible ticks of the clocks escapement and pendulum, and then determines the beats per minute and the rate of error in seconds per day fast or slow.

This app has been created specifically in mind for both the clock owner who just wants to know how fast or slow their clock is per day to adjust it, and also for the professional horologist for in depth testing of movements or field work.

For the clock owner it is a simple process of mic calibration, putting the clock in beat with apps help and then the measurement takes place. An error rate will be shown and you can adjust the clocks pendulum accordingly.

For the professional horologist or interested amateur, you can now test and regulate in the field accurately - put the clock in exact beat, regulate the clock accurately with only a few minutes of testing. On the bench you can test for long periods for increased rate accuracy and stability. The rate is a running average so the longer the test, the more accurate the rate. Accuracy of BPM's to the 4th decimal place and rates accurate down to +/- 1 second a week (in-app upgrade). You can add external sensors to also aid in accuracy. There is an added feature for saving the raw tick times in a data file that can be imported to your favourite spreadsheet for graphing and in depth study of escapements and wheels (in-app upgrade).

The app works on any pendulum clock - a longcase, mantel, wall, bracket, dial or carriage clock, et cetera. Also works with quartz clocks or anything that produces an audible tick that you would want to measure or regulate.

Sensor Update Feb 2017

For best results we now recommend the use of the Peterson Vibration pick-up.

It is a piezo-acoustic contact sensor, with clip mount and requires no additional adapters to connect to the iPhone! It provides the best vibration pick-up and is not affected by room noise.

> Peterson PitchGrabber on Amazon <

Note that similar products such as Peterson TP-3 do not work with iPhone.

It is imperative to mention that the longer your test sample is, the more stable and more accurate the Error Rate will be. A test of at least ten minutes or more should be conducted for a Rate of any value. 30 minutes or more will allow for more complete analyzation of the data should you wish to go more in depth for troubleshooting purposes.

Putting The Clock In Beat

You will not be able to achieve perfect zero due to the inherent errors of the clocks escapement teeth. Adjust as close as possible. For example, on a mantel clock you can level the clock by raising one side or the other of the clock by small amounts and listen for even ticks. Watch the Δ for finer adjustment. If the clock is on the wall, then move the bottom of the case left or right by a small amount and listen for evenness in the ticks. Again use the Δ for finer adjustment. For gross adjustments, the pendulum crutch needs to be adjusted. This should only be attempted by a qualified clockmaker.

Clock Time Regulation

After a stable Error Rate has been determined, the weight on the pendulum needs to be raised or lowered by turned the nut or screw holding it onto the pendulum. Small amounts are all that are necessary. Half a turn is a good starting point for a minute of error. This of course will vary greatly depending on the type of clock and length of the pendulum. Let the pendulum settle its swing before retesting. Some mantel or bracket clocks are adjusted from the front of the dial with a key. This adjusts the length of the pendulum and has the same effect. Again small adjustments.

Data File Saving & Use

The raw data measured time between ticks is saved in a .txt file. These times are measured to the 15th decimal place. An example of the data file is below:

These times can then simply be imported to your favourite spreadsheet for further use. For example, the times can then be charted or used to figure the BPM for each tick, or the running error average at each tick and then charted. Each chart would then have its own information to give. A specific pattern can be found, an instability figured or a bad tooth on a wheel can be found.

60 BPM Single Pallet Tooth Eccentricity

60 BPM 10 Minute Error Rate Chart

60 BPM 30 Minute Error Rate Chart

Should the need arise, a full range of conservation and restoration services of your antique clock can be provided by: