The race towards nothingness in ultra-thin watches has picked up in the last years, with brands like Bulgari and Richard Mille outdoing each other in the thinnest-watch stakes. Now Konstantin Chaykin wins the race with his ThinKing, a prototype that comes in at a staggering 1.65 mm in back-to-back thickness — making it the thinnest mechanical timepiece today.

Currently the ThinKing is a concept watch in its second prototype stage, constructed and executed by the Moscow-based independent watchmaker, with three pending patents linked to its development. 

Initial thoughts

While the technical merits are impressive, the watch seems bland on its face, or at least face-on. It appears to be a large, flat piece of steel with a dull finish, sporting twin eye-like registers for the hours and minutes.

The ThinKing doesn’t have the visual flair of Richard Mille RM UP-01 Ferrari or Bulgari Octo Finissimo Ultra. But it is easily recognisable as a Wristmon, the brand’s signature collection of “rolling eye” watches. Since it is only a prototype and the aesthetics are not yet refined for commercial production, the ThinKing’s appearance can be overlooked.

The brand name engraved in an arc resembling a smile

The ThinKing is absurdly thin at 1.65 mm. This makes it 0.05 mm thinner than the previous record holder for the thinnest mechanical watch, the Bulgari Octo Finissimo Ultra Mark II.

Although imperceptible to the naked eye, the minute reduction is amazing from a technical point of view. It is especially impressive since it was conceived and produce entirely in-house by a small-scale independent watchmaker, as opposed to big brand with resources as well as the help of specialist suppliers (the movement in the Bulgari was developed by Concepto).

A thin and planar movement

In tackling ultra-thin watches, watchmakers have either turned to specialised modern materials that can be machined to extreme tolerances while keeping their structural integrity, or at rethinking core horological concepts and movement architectures.

Being the inventor that he is, Mr Chaykin radically rethought the classic movement layout. He realised that in a conventional movement, the components of the going train, from barrel to oscillator, can built on a bare minimum of two levels: one for the coaxial wheel and a pinion mobile. 

Mr Chaykin worked to reimagine the entire going train on only two levels, which is particularly difficult to do with the balance and mainspring barrel, since their function typically requires a multi-levered construction. The result of his unconventional thinking is the ultra-thin calibre K.23-0, which is spread out and built into the case of the ThinKing. 

One component that Mr Chaykin completely redesigned was the barrel. He dispensed with the classic barrel covers, ratchet and click. He then moved the ratchet inside the barrel arbour, which means the winding works take up the unused space at the barrel’s centre. The barrel is as thick as a conventional pinion-and-wheel mobile, meaning it fits with the “two level” concept of the movement.

This invention brought down the barrel thickness without compromising on reliability. The ThinKing runs for 32 hours on a full wind. 

The second component that was fundamentally redesigned was the balance. Conventionally, a balance has four levels: the impulse pin, security roller and dart, the rim of the balance and lastly the hairspring itself.

For the ThinKing, Chaykin “unfolded” the balance, distributing its various functions over two balance wheels geared to one another. The Swiss lever escapement interacts conventionally with the first balance wheel, which in turn engages the second balance wheel. The hairspring is fixed inside the thickened rim of the second balance wheel and makes the whole assembly oscillate at 2.5 Hz. 

This reinterpretation of the balance wheel allows the escapement geometry to be left intact, with all the suitable angles and security implements — unlike the Richard Mille RM UP-01 Ferrari, where the optimal escapement geometry is compromised by the construction choices. 

The time telling is done by two large wheels geared to the going train, visible through 0.35 mm thick sapphire widows. The watch has no crown, because the time-setting and winding are done through a special carrier case dubbed PalanKing. The PalanKing fits over the case back on the ThinKing and connects to the barrel and time-setting yoke. 

The PalanKing has a crown, through which the user can wind and set the time on the ThinKing and also a micro rotor, which can wind the ultra-thin watch automatically. The ThinKing can be worn on the wrist with the PalanKing carrier on — which might be convenient because of the automatic winding module and the impression of increased rigidity it gives. The mechanics inside the Palanking form a movement of sorts, the K.23-1.  

The 40 mm diameter case of the ThinKing Prototype 2 is made out of an unnamed, proprietary stainless steel alloy. The case is built to also function as a main plate for the movement, a fairly customary practice in the realm of ultra-thin timepieces. Without the strap, the ThinKing weights only 13.3 g.

Because of the inventive movement and gear train architecture, Chaykin was able to use classic jewelled pivots and stayed away from ball bearing fixings, which he considers unreliable. As a result, the K.23-0 runs on a total of 51 jewels. 

The last invention particular to the ThinKing is for the strap. Such a thin watch is admittedly more susceptible to shock-induced damage, so Mr Chaykin came up with a dedicated strap with titanium fixings and elastic inserts which take any torsional stress away from the case and dampen any shocks. 

Key facts and price

Konstantin Chaykin ThinKing 
Ref. K.23-0

Diameter: 40 mm
Height: 1.65 mm
Material: Stainless steel
Crystal: Sapphire
Water resistance: No

Movement: K.23-0
Functions: Regulator-style hours and minutes
Winding: Manual, but self-winding with PalanKing attached
Frequency: 18,000 beats per hour (2.5 Hz)
Power reserve: 32 hours

Strap: Black alligator leather with titanium supports and elastic inserts

Limited edition: One-off prototype
Availability: Serial production of a refined version expected in the future
Price: Not applicable

For more information, visit Chaykin.ru