Things that come apart
Getting inside a wristwatch
NOTES: Sure, Shinola’s movements use Swiss parts. If you want a good timekeeper, you get the parts from Switzerland. But the folks doing the hard part – assembling the tiny pieces into a watch – are all-american. Even Olivier de Boel, Shinola’s factory manager, who explained to us in exacting detail how the watch works, was in awe of the keen eyesight and steady hands required to build one of the company’s timepieces. And with the exception of dispensing lubricating oil and checking for imperfections, the craftsmen do the work without magnification. Which is more than we can say for the picture at right.
The movement – the parts of the watch that produce its measurements of time – is constructed like a round metal sandwich. The main plate (13) is the bottom piece of bread. The fillings are the power system, the processor and the gear train that turns the watch’s hands. Bridges (18) are like the intermediate piece of bread in a double-decker: metal plates that properly space the parts and provide protection and rigidity. The top piece of bread is the dial support (12), which circumscribes the date rings, the uppermost portion of the movement.
The Runwell has a quartz movement, in which the ticking is regulated by a quartz crystal that is integrated with a microchip in the electronic module (16). Quartz is piezoelectric: electricity causes it to vibrate. When current from the battery (2) is sent through the crystal, it vibrates at 32 768 Hz. From this the microchip derives an electric signal that pulses once every second.
THE CURRENT TIME
The electric pulses are directed towards a coil (3) to generate a magnetic field. The coil is linked to a stator (23) through which a rotor (14) protrudes. The magnetic field causes it to rotate 180 degrees every second. In effect, this creates an electric motor whose engine speed is measured, not in revolutions per minute, but seconds.
The gear that links the motor to the readout on the dial (4) is called the cannon pinion (8); the gears that correspond to specific units of time are called, unsurprisingly, the second wheel (5), minute wheel (22), and hour wheel (27). The watch’s hands (1) mount to the gears with a press-fit system: posts on the underside of the hands seat in cylinders centred on the gears. The system is lubricated with small amounts of oil in little red compartments called jewels (17) because they used to be made of hard precious stones that would resist wear. Today, they’re smooth, synthetic ruby.
The time is set manually by pulling the crown (9) on the end of the setting stem (10) to the second of its two positions. In this position, its setting lever (15) engages the minute wheel, so that as the crown is rotated, the minute and hour hands turn. (The cannon pinion acts as a clutch so the motor doesn’t fight the wearer as they set the time.)
The date function is linked to the timekeeping gear train, and is set by pulling the crown to its first position. Whereas some watches use a single date ring numbered from one to 31, the Runwell uses two rings, the units indicator (19) and the tens indicator (20). The tens indicator is positioned on top and has windows (21) that show the units digit, unless it is the 20th, 30th, or 31st day of the month.
There are three more small electric motors regulated by the quartz’s vibrations, all for the chronograph: one for its tenths-of-a-second hand, located on the six o’clock subdial (25); another for minutes and hours, located on the nine o’clock subdial (26); and one for the large second hand. If the chronograph is not being used, none of these motors receives electricity. But if the wearer presses the top button (6) on the case (24), its spring (7) activates a circuit that delivers power to the motors and the hands turn. When the bottom button (11) is pressed to reset the chronograph, the microchip delivers enough pulses to return all the hands to the 12 o’clock position. – Kevin Dupzyk
A PHOTOGRAPH BY TODD MCLELLAN