The Reason
An example of a skeletonized flying tourbillon with power reserve and unusual setting mechanism.
The Octo Roma Tourbillon Sapphire watch is manually wound, carries a flying tourbillon turning on a ceramic ball race and has a power reserve indication viewed from the back.
The titanium case is 44mm in diameter and 12.45mm thick with a sapphire central ring allowing light to enter the case easily to view the calibre. Water-resistant to 50m. The movement: BLV206 is 34.00mm in diameter and 5.00mm thick. Power reserve of 64 hours. The balance wheel oscillates at a frequency of 3 hertz, (21,600 vibrations/hour). There are 20 jewels set into the calibre.
Please move the cursor across the image below, (or by finger on a smart phone), to rotate the watch.
Profile image of the case showing the titanium pillars and view of the calibre through the sapphire ring.
The strap removed from the case highlighting the overall architecture of the design.
The sand blasted surface allows the black DLC treatment to be stronger than conventional applications on polished cases.
The titanium case is sand blasted after manufacture to generate the even matt surface then treated with a black DLC (diamond like carbon) treatment.
The setting mechanism is adjusted by pushing the crown (as with a mono pusher chronograph). When the ‘red’ spot is viewed the hands can be adjusted, after pushing the crown a second time the red spot disappears and the watch is in winding mode.
The case is held together by 4 long pentagon headed screws/bolts. Below can be seen the tool used to tighten and loosen the screws. The screws traverse the case back sapphire ring and tighten into the bezel holding the construction together with 11 pillars. Each pillar aligns with the hours on the main-plate. The screws pass through 4 of them, the remaining 7 reinforce the overall construction of the case and compliment the aesthetic of the skeleton design.
The dismantled case
The 4 screws in place illustrating their length which travel through to the bezel.
The inner case showing the circular milled out sections which hold the pillars in place.
The 11 case pillars, The 3 o’clock position is absent of a pillar due to the winding crown.
The bezel with sapphire glass which is branded on the inside and treated with anti-reflective coatings.
The movement in the sapphire ring and one of the large casing rubber seals used to ensure the watch is water resistant to a depth of 50 meters.
Images of the back of the watch showing the power reserve indication. All of the hands, and indexes are sandblasted and plated with a rose gold layer assuring congruency in design, and the main-plate to be cleaned conventionally when the watch is eventually serviced.
The minute and hour hands; the luminescent SLN (Super LumiNova) material is added by hand from the back after the metal has been decorated and plated.
To remove the movement from the case the stem needs to be freed from the calibre. The large screw in the centre which holds in place the pillar/column wheel also acts as a locking device for the stem. To remove the stem, it is unscrewed (as shown) and then the stem can be pulled freely out of the watch.
Once the stem has been removed, the 2 case clamps (one shown below in the centre of the image) are dismantled and the movement is free to leave the sapphire ring.
Recto-verso of the movement free from the case, with the minute and hour hands removed.
Setting and winding positions.
Winding position
Setting position
The upper crown wheel (left), to its right the large ratchet wheel connected to the barrel which houses the mainspring powering the watch.
The flying tourbillon is driven by the last wheel in the going train meshing with an extended pinion fixed, to the tourbillon cage above the ceramic ball race. The three screws forming a triangle around this pinion secure the cage in position onto the main plate.
The flying tourbillon implies a tourbillon which is supported and pivots only on one side allowing a clear visibility of the complete assembly.
The central bridge removed which holds in place the motion work (minute, hour wheels and intermediate pinion), and covers partially the setting mechanism. Creating the window for the red indication of the winding/setting position.
Close up of the setting mechanism and the skeletonised barrel showing the mainspring fully unwound. The watch is in setting mode with the sliding cutch meshing with the motion work to adjust the hands.
The ratchet wheel loosened from the barrel arbour showing the click spring partially hidden underneath.
The main bridge removed which holds in place the going train as well as the power reserve.
The going, and power reserve train partially removed.
Recto-verso of the tourbillon cage. The balance is free sprung, regulated with 4 timing screws set into the rim of the balance wheel.
The synthetic sapphire jewels in the Kiff protection have been made transparent to associate with the calibre’s aesthetics
The large block below the pinion is the ball race upon which the cage rotates and is held by.
The three main assemblies of the tourbillon. The lower bridge with escapement, the balance wheel and upper cage bridge.
The escapement lever below is 4.139mm in length.
The upper pinion drives the cage via the last wheel in the going train. The lower pinion is fixed to the escape wheel and drives the escapement.
Below can be seen the precision ceramic balls upon which the cage rotates.
Summary
The Octo Roma Tourbillon Sapphire watch design inspired by early Italian/Roman architectural influences.
Columns surround the inner sapphire ring of the case. The sapphire allows light to enter the case laterally increasing the visibility of the movement.
Despite the large sapphire ring which creates the majority of the material volume of the case, it remains light in weight. The movement appears simple in construction. There are still 291 components used to build the calibre but once finished the result is clean, uncluttered.
The unusual and technically flamboyant setting mechanism adds an additional technical element to the calibre.
One of the watchmakers tailored movement holders used to support the calibre whilst being assembled.
All manufacturers complications have idiosyncrasies that require specialised tooling and supports. These tools are often then modified by the watchmakers that assemble the watches to facilitate the manipulations that are performed.
A bullet shaped support for assembling and adjusting the tourbillon cage.
Diverse images of the finished watch.
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