“A man who dares to waste one hour of life has not discovered the value of life.”
~ Charles Darwin

IWC has long been a widely respected, top-tier, watch firm for over 100 years. Although they have single handedly set the standard for pilot watches, the IWC “Da Vinci” Perpetual Calendar Chronograph (Ref. 3750) was an epic statement of IWC’s arrival as one of the premier watchmakers of our generation.

IWC introduced the Da Vinci at the 1985 Basel Fair. Kurt Klaus, one of the most respected Master Watchmakers at IWV, and a former apprentice of watchmaking wonder Albert Pellaton (of Pellaton winding fame), designed a synchronized caliber, using only a single crown for time, moonphase AND perpetual calendar adjustments.

At the time, the retail price was half of the next lowest priced perpetual calendar (much less a perpetual chrono). And, unlike so many perpetual calendars, the Da Vinci allows setting of the many calendar indications from the crown, versus the much more common system of push buttons set into the case sides of other perpetual calendars. The caliber itself is also very robust, and has gone on to be the best selling perpetual calendar caliber of all time. Unbundled from the chronograph, this same calendar mechanism appears in the Jaeger LeCoultre Odysseus, the Jaeger LeCoultre Master Perpetual (Ref. 140.240.802B), the IWC Novecento perpetual (Ref. 3546), the IWC split-second version of the DaVinci (Ref. 3751); and later, the IWC hand-wound Portofino Perpetual (Ref. 2050), with a movement thickness of 3.15mm, the slimmest perpetual calendar every produced.

    • First perpetual Calendar ever displaying years via aperture
    • First perpetual Calendar ever with all adjustments via crown only (no pushers on case)
    • First perpetual Calendar ever with Perpetual moon phase having accuracy of only 1 day deviation in 122 years !

The genius of the one crown day, date, month, year, time adjustment proved unequivocally that IWC was now part of an elite haute horlogerie fraternity. Crown aside, such a complication is an exercise in engineering intellect, taking into account years that can be divided equally by 4 and centuries that can be divided equally by 400 and the perpetual calendar accounts for leap years by that calculation. Accurate to one day per 144 years, the IWC “Da Vinci” Perpetual Calendar Chronograph was also the first to display full four digit years.

This watch encompasses one of the most extreme reduction gear ratios in the history of watchmaking: 1:6,315,840,000. 
This means that in the course of 100 years, the balance completes no fewer than 252,450,000,000 oscillations before moving the century slide just 1.2mm upwards !!

Typically so long as you keep a perpetual calendar watch wound and running, they stay synchronized. However, let the mainspring run down and you have resetting problems. Having to set all the displays individually can be awkward. Cleverly, all the displays on the da Vinci stay synchronized and can be easily set using just the crown, something which was revolutionary and one of the reasons it became so popular.

The dial is black, and before I forget to mention it, the moonphase disc has the prettiest stars of any I have seen. Applied hour markers and straight hands, both with luminous. The dial is very complex:

    • At 12 o’clock is a subdial for chronograph 30 minute totalizer and moonphase
    • At 3 o’clock is the date indicator
    • At 6 o’clock is the month and 12 hour chronograph indicator
    • At 9 o’clock is the constant seconds and day indicator
    • Between 7 and 8 o’clock is a 4 digit year indicator, showing not only year but also century!

The Da Vinci model (Ref. 3750) went on to become the most widely sold perpetual calendar watch in history. It not only had a number of unique features but also retailed for half the price of its nearest competitor.

Maintenance:
    • Except for the regular maintenance, the perpetual calendar does not need any adjustment.
    • 1st adjustment: March 1, 2100 – Since the leap year will be skipped that year, adju
    • 2nd and final adjustment: January 2, 2200 – New century slide (shown above, in small glass capsule) will need to be installed.

Specifications:

Calibre & Movement:

  • Calibre: 79261
  • Movement Ref.: 3750-28
  • Mechanical chronograph to 1/8th second
  • Self-winding
  • Perpetual calendar
  • Movement diameter : 30 mm (13¼ Paris Lignes
)
  • Movement height: 8.80 mm
  • Power reserve: 44 hours
  • Copper-colored, fausses cotes decoration
  • Jewels: 39
  • Straight-line lever escapement
  • Monometallic balance
  • Shock absorber
  • Self-compensating flat balance spring
  • Impulse angle : 52 degrees
  • Oscillating frequency : 4.00 Hertz
  • Halfbeats per hour : 28,800

Case:

  • Material: Polished stainless steel
  • Dial, case and movement signed
  • Two body, polished, stepped bezel, hooded mobile lugs
  • Crown: Screw-down
  • Case back: Screw-down
  • Glass: Acrylic, convex, anti-reflective coating
  • Water Resistant: 30 meters (3 bar)
  • Case diameter: 39 mm
  • Case Thickness: 14.3 mm

Dial:

  • Black
  • Applied steel baton indexes and luminous dots
  • Subsidiary dials for seconds, 12-hour and 30-minute registers
  • Subsidiary dials for days of the month, of the week and the months
  • Aperture for 4-digit year
  • Aperture for moon phases
  • Luminous steel baton hands