ochs und junior ochs line anno 42mm

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This is the one you’ve all been waiting for, the latest addition to the ochs line, the anno in 42mm. Available in two color options in our exclusive ochs blue, and in one “not-so-basic” black.

Of all of Ludwig Oechslin’s wonderful creations, perhaps the most iconic is the ochs und junior annual calendar or anno. A wrist-bound time machine that provides not only the time, but the date (day and month), and the day of the week.
Unlike a typical date or day-date watch, it will only need to be adjusted on March 1 of each year.

Less is more

An annual calendar, by definition, is complicated. But Ludwig Oechslin has always looked at things a bit differently. Three years of research and development led to a new annual calendar function that is comprised of just 3 additional parts.

Innovation within reach

One of Dr. Oechslin’s biggest goals was to be able to offer his innovative watches at a more accessible price.

The ochs line anno in 42mm is priced at
CHF 5’500 – incl. 7.7% Swiss VAT
CHF 5’077 – Export price.
Available in 12-20 weeks.

1 | anno oj blue and brass
the first of the three non-customizable models of the ochs line anno 42mm

42mm case | Grade 5 titanium | oj blue dial, date disk, month wheel, weekday wheel | Super-LumiNova markers in brass | Super-LumiNova hour and minute hands in brass, oj blue second hand | Super-LumiNova date dot, month dot, weekday dot in brass | Ecopell dark blue “Enzian” leather strap (S/M/L/XL) and leather pouch handmade by Sabina Brägger.

2 | anno in oj blue and orange
the second of the three non-customizable models of the ochs line anno 42mm

42mm case | Grade 5 titanium | oj blue dial, date disk, month wheel, weekday wheel | Super-LumiNova markers in orange | Super-LumiNova hour and minute hands in orange, oj blue second hand | Super-LumiNova date dot, month dot, weekday dot in orange | Ecopell dark blue “Enzian” leather strap (S/M/L/XL) and leather pouch handmade by Sabina Brägger.

3 | anno black and white
the third of the three non-customizable models of the ochs line anno 42mm

the third of the three non-customizable models of the ochs line anno 42mm
42mm case | Grade 5 titanium | Black dial, date dis k, month wheel, weekday wheel | White Super-LumiNova markers | White Super-LumiNova hour and minute hands, black second hand | White Super-LumiNova date dot, month dot, weekday dot | Ecopell black leather strap (S/M/L/XL) and leather pouch handmade by Sabina Brägger.

Summary & overview

An annual calendar watch accounts for months with 30 or 31 days. The date therefore only requires manual adjustment once per year on March 1st. Conventional annual calendar watches display the date, month and weekday using text and numbers. They use levers and springs and comprise many parts.
Oechslin invested 3 years in developing a new annual calendar function comprised of just 3 additional parts (see video), because fewer parts imply fewer interactions between parts and higher reliability. All functions can easily be set using the crown.

Date
The 30 + 1 holes around the perimeter of the dial display the date with 10-minute markers serving as reference points. For example: the marker indicating 30 minutes also shows the 15 th day of the month (30 ÷ 2 = 15). These 5-day markers allow for the date to be read at a glance and intuitively. The date only needs to be adjusted once a year on March 1st.

Weekday
The 7 holes display the weekday (counterclockwise rotation). You can choose which weekday you would like to display at the top. The interactive watch above is set to Sunday.

Month
The 12 holes display the month (counterclockwise rotation).

Day/night
One visible weekday dot indicates daytime (6am to 6pm). Two visible weekday dots indicate night time (6pm to 6am).

Time
The exact minute and second can be read using the date holes, which are spaced at 2 minute intervals.
Holes mark even minutes and gaps odd minutes. The holes and gaps are exactly the same width as the minute hand.

Mechanics
How is Ludwig Oechslin’s annual calendar unique?
Oechslin executes his annual calendar as a gear system using only the following custom-designed parts:
• Dial that serves as a module in the gear system (left)
• Month disk and cog with 5 teeth, double-toothed (center top)
• Collar with two fingers bonded to the hour rod (center)
• Weekday disk (center bottom)
• Date ring (right)

The month, date and weekday indications are actually inscribed directly on the front-side of the functional parts – an annual calendar can’t be reduced further.

How does it work?
Two additional fingers are bonded to the hour rod which drives the weekday disk and, via the 5 longer teeth on the month disk, imparts an extra impulse to the month disk on months with 30 days or less (February). The month disk receives power from the toothed date ring via the 5-tooth cog.

What was Oechslin’s motivation for using gears?
With their turning wheels, gears lend themselves to Oechslin’s goal of displaying the date, month and weekday in analog fashion, like the hands on a watch. An analog display is more readable than a digital display or alphanumeric characters displayed in a window on the dial. Gears also allow the annual calendar function to be executed using very few parts. Fewer parts leads to higher reliability of the functions – and easier servicing. Finally, Oechslin’s gear system enables the date to be adjusted quickly via the crown; there is therefore no need for additional pushers like in conventional annual calendars. He enjoys the intellectual challenge of designing watches in the most technically elegant and functional manner possible.