It’s Familiar – But Never Seen Before
A patented time display that looks so familiar you think you have seen it before. Yet, a precise time display with a single hand, so new it needs explaining.
This reads like a Koan for a Zen student. But it has become our big challenge in communicating the essence of SNGLRTY. Neither Steve nor I anticipated this problem. Our focus was on the physical realization of the SNGLRTY time display. Our concept had to be rendered into engineers’ drawings, resulting in our One Hand Indication (OHI) complication plate. Despite, or perhaps because of, the originality of the time presentation, we wanted to maintain a familiarity with the classic two-hand display. Classic watches generally also display the first complication, the date, which we wanted to maintain in SNGLRTY. Our problem right now is that merely describing the functions does not help.
Why Are The Minutes Separated From the Hours?
Steve and I knew that our time display was peerless. We spent a lot of time verifying this for ourselves and were ultimately rewarded with a patent. But why was this? Could it have been the other way round?
It was not until the end of the 17th century that the gear trains of clocks could be designed and manufactured with enough precision that the display of minutes was possible. At this time, a decision was made to change from a single-hand hour hand on the display to two hands, one for the hour and one for the minutes.
This is the classic two-hand display that is ubiquitous. Each hand indicates the hour or the minutes on a circular dial and using different indexes on the dial. However, even then, it would have been possible to detach the minutes from the circular index and instead synchronize the minutes with the hour hand’s position. If this had been the case, Steve and I would certainly not have received a patent for our ideas. SNGLRTY would have been ubiquitous, and perhaps Steve and I would have invented the two-hand analog display in September 2016 in the bar in old Wan Chai, Hong Kong.
There are many reasons why clock history did not turn out this way. However, the SNGLRTY display could have been the primary display that informed our choices for developing our watch concept. SNGLRTY would be an automatic wristwatch made in Switzerland. The physical design would be based on the classic dress watch but enriched with design twists and incorporating a little bit of our individual personalities. All of this led us to decide that SNGLRTY should be available with the classic date display.
If You Cannot Find It, Make It!
There is no standard movement available on the market for the SNGLRTY display. The minutes rotate backward slower than a regular minute hand travels forward. And at a slower speed. This was a particular challenge for us as we moved from concept to execution in the development process. Our only solution was to develop our own in-house in house movement. This can be a tricky, complicated, time-intensive, and thus expensive process if the movement is developed from the ground up. We decided to follow the tried and tested route of incorporating a complication plate to reduce the risk, time, and expense.
In this implementation, a base movement or tractor movement is selected for the basic watch and timing functions, such as the winding mechanism, the gear train, escapement, and timing wheels. The complication plate is then applied on top of the tractor movement to render the final complication desired. In our case, we wanted the complication plate to be flexible so that it can be combined with different tractor movements, and it should ensure that the calendar complication is available if desired.
The calendar function has a fascinating and intricate story behind it, which I wrote about a few weeks ago. If you are interested in understanding more about the history of the date display, the various calendar functions on clocks and watches, and its significance for SNGLRTY, you can read it HERE.
Of Hands And Discs
Displaying the date using a central sweep hand is easier to manufacture than the now well-established sub-dial disc. A. Hammerly from La-Chaux-de-Fonds was aware of this when he applied for a patent for his date display in 1915. This was despite the fact that he had also applied for a patent for a display that presented the day of the week on a disc below the dial that would be revealed through an opening at the 12 o’clock position. Where the date is displayed using a hand, the 31 days are often displayed around the full circumference of the watch face.
The hand often has a graduated circle at the furthest radius that indicates and visually emphasizes the date number. The date numerals can be printed larger or smaller on the dial, depending on the diameter of the dial. However, as the date index should not interfere with reading the time, they are usually discreetly small. The date hand alone does not indicate the date by its position, therefore reading the corresponding number is necessary. For this, however, the numerals are often too small for easy reading.
There were also problems with the implementation of the sub-dial disc date display. Until the invention of the large date, the date display was characterized by small numbers, squeezed into a small opening at the three, six, or sometimes 4:30 position. Both types of date display, either with a hand or with a disc, had their limitations.
Seconds Indication or A Compass?
The DNA of SNGLRTY has always been accuracy for a single-handed watch. Logically a date display using a hand was out of the question for us. Even before this, we had to compromise by including a second hand. But was it a compromise?
We do not think so. SNGLRTY, unlike conventional one-hand watches, is committed to accuracy, so it should be possible to set your watch to the second. This was the first reason for including a second hand. In addition to this, we wanted to ensure the wearer can confirm the watch is operating easily. This confirmation can be done quickly by observing the rotating second hand.
So, the second hand is not another hand on the watch face for our way of thinking. We made it short and also drew it with a congruent counterweight. Our idea was that it should be more of a decorative element. The two halves of the second hand are different colors (red and metallic), and for the wearer, it does not matter which end is used to set the time.
Yes, the second hand is reminiscent of a compass. Many people have pointed this out to us, but I can assure you that we did not overlook this design similarity. Our goal was to align it with a power reserve indicator rather than a second hand used for accuracy. To do this, we went for a twist to the classic watch.
To achieve our goal of the date on SNGLRTY, the date driver from the tractor movement had to be transferred onto the top of the complication plate. If this were not done, the date would appear to lie lost in the depths of a well in the watch face. For us, though, moving the date to the top of the complication plate opened up the opportunity to display the calendar numbers on a larger diameter. The diameter of the SNGLRTY movement, with the complication plate attached, is 7.6 mm larger than the diameter of the tractor movement. This increases the circumference of the date disc by 36% and the width of the date aperture by 20%. The effect of our date complication is to create a Big Date that lies directly under the dial and has improved readability.
The Graphical Crime Of Every Date Disc
It is a little-known fact that printed date discs look terrible when fully visible. This is especially the case where the date aperture is at the “six” positions. The reason for this ugliness is quite simple. All the numbers are aligned with their radius so that when they reach the six location, they are vertical. Each number is adapted to the date aperture to achieve the greatest possible legibility to make it as large as possible. The “1” must appear as bold as possible, while the “22” runs out of space because the lower, horizontal lines require more space. For example, the numeral 2 of “21” is larger than that of “22”. All watch designers try to manage this within the spirit of the chosen typeface, but the graphical tolerances are already materially stretched here. Thankfully, nobody notices the graphical crime when only a single number is displayed, and there is no easy comparison.
Direct Pass To The Complication Plate
The SNGLRTY complication plate has been designed to be as flexible as possible. It fits both the SW200 and SW300 movements from Sellita and is available in a version without the date display (OHI2) and with the date display (OHI4). The complication plate without the date display is assembled from 23 unique pieces manufactured exclusively for SNGLRTY. If the date indication is included, then there are 40 parts in the complication plate.
In constructing the minute display, we aimed to change the tractor movement as little as possible. This means that it should maintain all its accuracy and robustness, as there are no changes.
The date display is generally driven by the minute pinion in the middle of the movement. For the date to change, the rotational velocity of the minute pinion is transferred from a component with a small diameter, the minute pinion, to a component with a much larger diameter, the date disc at the edge of the movement. This is more complex than initially presented, as it is necessary to remove angular errors during the date change.
To move the date display onto the SNGLRTY complication plate, the date driver from the tractor movement is passed directly to the complication plate. For this, we replace the date disc of the tractor movement with our own unprinted one onto which we directly mount the internal date wheel using 4 pins. The internal date wheel is a large wheel of 22.597 mm with external teeth. This adapted date disc with its internal wheel rotates clockwise with a 360° rotation every 31 days.
The rotation of the internal date wheel is transferred onto the complication plate by the small date wheel (route date 3 below) and transferred vertically up to the slightly larger wheel above it (route date 2 below). Both date wheels are firmly connected and consequently turn counterclockwise together.
Technology meets Philosophy
Wheel 2 now directly meshes with the large date wheel (route date 1 above), that is firmly attached to the new SNGLRTY printed date disc. An alternative explanation is that the roue date 1 is a counterpart to the internal date wheel that rotates as the date disc on the tractor movement. This internal date wheel transfers its rotation through the gear train of roue date 3 and roue date 2 vertically up through the complication plate to the roue date 1. Roue date 1 drives the new calendar disc located on the top of the complication plate.
The roue date 1, because of its geometry, has teeth on its internal circumference. This may not seem startling, but because of the small working diameter, it was a challenge to mill these teeth. There is a very limited number of workshops in Switzerland equipped with the appropriate machines to make this component. This was just another small obstacle we faced on the journey to create the SNGLRTY complication plate.
Another interesting quirk is that the SNGLRTY date disc rotates with the roue date 1 with internal teeth, this drives roue date 2 counterclockwise. Therefore, with SNGLRTY, not only do the minutes rotate counterclockwise, but the date too.
With the counter-clockwise rotating date, the technical concept symbolizes the philosophy behind the SNGLRTY time display, “Be aware of each moment. Pay attention to what you spend your time on.”