DynaPoise

Setting Up the Geartrain

First, you must configure the geartrain in DynaPoise Geartain Analyzer to precisely match the geartrain in the watch.

To do this, you will need to do the following:

Disassemble the main geartrain from the watch movement. The main geartrain consists of the mainspring barrel, center wheel, third wheel, fourth wheel, and escape wheel. Almost all watches have five gears in the train, but you can optionally select four or six if needed.
Count the number of teeth on the mainspring barrel, and input the count into the Wheel 1 section in the Wheel Details section of the configuration panel.
For the second wheel (or center wheel), third wheel, fourth wheel, and escape wheel, count both the number of teeth on the wheel and leaves on the pinions, and input them into their respective fields in the Wheel Details section of the configuration panel.
As you enter the wheel details, a representative graphic is dynamically built to show the wheels, pinions, and their interactions.
To complete the geartrain analysis, you must enter the known rotational period of one wheel. In most watches, the fourth wheel completes one revolution per hour, or 3600 seconds.

Calculation Results

The right side of the page is divided into two panels, the Geartrain Rendering panel which shows a visual representation of the geartrain and its attributes, and the Geartrain Details panel, which shows the calculated values for each mesh point in the geartrain, as well as some other attributes such as beats per hour (BPH) and total gear ratio.

Rotational Period for each wheel in the geartrain. This is how long it takes each wheel to complete one full revolution.
Gear Ratio for each mesh (where a wheel and pinion interface) in the geartrain. The gear ratio is represented as a ratio of teeth on the wheel to leaves on the pinion. It can also be read as how many turns of the pinion will result in one turn of the wheel.
Calculation: (wheel tooth count / pinion tooth count) : 1.
Tooth Passage Interval for each mesh in the geartrain. This is the interval, measured in seconds, between successive teeth passing a fixed point in space. Said another way, this is how long it takes the wheel or pinion to turn one tooth's angular width.
Calculation: (360° / number of wheel teeth) * (wheel rotational period / 360°).
Hunting Tooth Interval for each mesh in the geartrain. This is the interval, measured in seconds, that it takes for a specific wheel tooth to meet up with the a specific pinion leaf twice. Calculation: ((n1 * n2) / (GCD(n1,n2))) * (wheel arbor period / wheel teeth), where n1 = number of pinion leaves and n2 = number of wheel teeth.
Total Gear Ratio for the geartrain. This is the ratio of the rotational period of the escape wheel to the rotational period of the mainspring barrel. Calculation: (mainspring barrel arbor period / escape wheel arbor period) : 1.
Beats per Hour (BPH) of the escapement. How many times the escape wheel tooth interacts with the impulse jewel in one hour, assuming a traditional swiss lever escapement. Calculation: (escape wheel teeth * 2) * (3600 / escape wheel rotational period).

Saving & Loading Configurations

Once you have your geartrain configured, you can save it by click the Save Config button on in the configuration panel. You will need to provide a name for the configuration, and you can optionally input a description.

To load a previously saved configuration, click the Load Config button, and select the configuration you wish to load.

Because the configuration is stored locally on your browser and never transmitted to the server, you can optionally back up your configurations to you computer's hard drive for safe keeping in the event your browser needs to be reset. To do this, click the Load Config button. In the bottom left of the load dialog, click the Export (up arrow) button to download a backup of your saved configurations.

To re-import your saved configurations, click the Load Config button, and then click the Import (down arrow) button in the bottom left of the dialog to select your backup file. The import function will merge your backed up configurations with any configurations that may already be present on your system.

Save Geartrain Configuration

Load Geartrain Configuration

Setting Up the Geartrain

Calculation Results

Saving & Loading Configurations

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DynaPoise

Geartrain Analyzer