A. Lange & Söhne Datograph

Introduced in 2005, the A. Lange & Söhne DATOGRAPH is equipped with modern day chronograph functions such as precision “jumping” minute counter, flyback mechanism, column-wheel gearing, 18,000 semi-oscillations, and outsize date.

The DATOGRAPH has set new chronograph-making standards by combining the finest aspects of tradition and innovation while prudently maintaining the highest technical and artistic values, as do the other well-known watches from Lange.

Comprising 390 individual parts, newly developed hand-wound chronograph movement features traditional yet highly advanced mechanical solutions such as a column ratchet wheel, a precision “jumping” minute counter, a flyback function and a transparent design that shows off the typical architecture of Lange movements with its three-quarter plate and elegant escapement around the hand-engraved balance cock. The DATOGRAPH also includes the patented outsize date.

The DATOGRAPH has an unconventional, very fresh new look with unique characteristics such as offset subsidiary dials for the small seconds hand and the classic 30-minute counter. The balanced arrangement of the dials leaves room for the outsize date mechanism and makes up the visually striking equilateral triangle that gives the DATOGRAPH such an inimitable face.

The tachometer scale and the luminous gold hour and minute hands add a complementary dynamic that is heightened by the split levels of the precious two-part dial in solid silver. The two subtly rounded chronograph buttons with the traditional square cross section correspond with the push-piece for correcting the outsize date. The design of the solid, three-part platinum case with the anti-reflection-coated sapphire-crystal glass bears the unpretentious signature that became one of the hallmarks of Lange watches following the company’s revival in 1994.

A glance through the sapphire-crystal caseback – secured by six screws, incidentally –at the calibre L951.1 movement is not only an aesthetic epiphany for fanciers of the finest in watchmaking: It also answers the questions raised on the front side. How does a top-class chronograph movement work? What about the ratchet-wheel assembly? What are the mechanisms of the precision “jumping” minute counter and the flyback gearing? 

The design of the movement aims for the greatest possible transparency, precision engineering in miniature, and holds numerous intriguing details for the connoisseur. Foremost among them is the precision “jumping” minute counter, which springs forward one notch at the precise moment when the centre stop hand of the chronograph passes 60 seconds.

This intricate mechanism, controlled by a stepped pinion, was once used only in very expensive pocket watches and in very few top-flight wristwatch chronographs until the 1940s, but in recent decades it has been sacrificed to cost-consciousness. The “precisely jumping” minute counter simplifies the doubt-free measurement of lap times. Lange not only accepted the challenge of truly accurate counting but also integrated it into the DATOGRAPH and even advanced its development one step further.

An adjustable switching lever is provided to very precisely set the jump point of the minute counter at the zero crossing point of the central stop hand without requiring the disassembly of the movement. A patent was pending for this ingenious invention. The flyback mechanism, used not only in aviation and sports, makes it possible during an ongoing time measurement to reset the chronograph hands to zero with a single push of a button and to restart them instantly by releasing the button.

This feature saves time because the flyback mechanism simply skips the stop, reset and restart manipulations for which two buttons are normally needed. This extra function is rarely implemented today. A look inside the movement reveals how it works.

Numerous other details of design and craftsmanship in this newly developed movement show that Lange was intent on raising the much-talked-about subject of chronographs to a new level of quality.

Apart from the remarkable functional elements described above, the DATOGRAPH has an unprecedented range of additional features:-

• A separate and independent fourth-wheel bridge
• A chronograph switching lever with a sturdy shaft secured by calliper bearings
• An adjustable chrono coupling lever in the centre of the fourth wheel
• A minute-counter switching lever held and guided between jewel bearings like a wheel
• A stepped pinion for the precise release of the minute-counter switching lever with its ruby sliding head
• A four-jewelled bearing for the escape wheel
• An independent escape wheel bridge
• A shock-proofed, oversized screw balance with a Nivarox 1 hairspring and a shaped overcoil beating at the tried-and-true 18,000 semi-oscillations like the classic Lange pocket chronographs.

And of course the DATOGRAPH, despite having a movement only 30 mm in diameter and 7.5 mm high, includes all the hallmarks of Lange’s watchmaking artistry: Plates and bridges in damascened silver elegantly filigreed with circular graining and Glashütte ribbing. The edges are chamfered and polished in visual contrast to the faceted blued screws. And in the DATOGRAPH too, the masterful lines of the hand-engraved balance cock make every movement unique.

The whiplash precision regulator and all steel chronograph levers, but also the imposing column wheel and the numerous springs, are all precision-ground and, where their function permits, additionally chamfered and polished. The polished, black cover plate adds a beautiful accent to the escape-wheel bridge.

As aesthetic finishing touches to this movement, the gold chatons held by blued screws are sumptuous highlights of contemporary chronograph-making. These are features found only in Lange timepieces.

Technical details

A. Lange & Söhne DATOGRAPH Platinum, Ref. 403.035

• Case: Ø 39.0 mm, platinum.
• Dial: Solid silver, black/ argenté. Hours markers at 3,9 and 12 o’clock luminous.
• Hands: Rhodiumed gold and blued steel. Hour and minute hands luminous.
• Glas and Caseback: Sapphire crystal glass.
• Strap: Hand-stitched crocodile strap buckle in platinum.

A. Lange & Söhne DATOGRAPH Pink Gold, Ref. 403.032

• Case: Ø 39.0 mm, pink gold.
• Dial: Solid silver, argenté/ rhodié. Hours markers at 3,9 and 12 o’clock luminous.
• Hands: Pink gold and blued steel. Hour and minute hands luminous.
• Glas and Caseback: Sapphire crystal glass.
• Strap: Hand-stitched crocodile strap buckle in pink gold.

Movement
Lange manufacture calibre L951.1, manually wound, 36 hours power reserve.
Precision-adjusted in five positions. Chronograph mechanism, flyback mechanism with precisely jumping minute counters, patented twin-disc mechanism for the display of the outsize date, stop seconds feature.
Plates and bridges made of untreated cross-laminated German silver, balance cock engraved by hand.
Diameter: 30.6 mm. Height: 7.5 mm.

Functions
Hours and minutes indication, small seconds hand with stop seconds.
Chronograph with flyback and precisely jumping minute counter. Patented outsize date.

• Find More Details about A. Lange & Söhne Watch Brand.

• A. LANGE & SÖHNE New Watch Models.

• A. LANGE & SÖHNE Archives (from 1994 to 2013).

Image Credit: Lange Uhren GmbH