A special challenge here was that both the original balance and hairspring of the Piguet movement should be used in the tourbillon. These constraints necessitated the "flying" mounting of the tourbillon cage. To place the regulator
as close as possible to the balance axis, Gerber made a new hair-spring with Breguet over coil and Phillips terminal curve (no. 57.5 according to the Phillips classification). He also implemented a new escapement with lateral pallet. That this (http://www.watchreplicahome.com/rolex-watches-daydate-watches-c-53_351.html) construction is also more sophisticated, more difficult to assemble and a more visually appealing construction are merely welcome side effects.
To place the tourbillon in the movement, the cocks for the balance and escape wheel and the bridge for the pallet lever had to be removed and extra space for the tourbillon cage and its intermediate wheels had to be milled into the movement's base plate. It bears repeating that the (http://www.watchreplicahome.com/breitling-watches-bentley-watches-c-17_146.html) pressure on Gerber at this stage, where ir- reversible alterations are made to the main plate of the movement, was immense. To account for the increased need of power for the tourbillon, two further modifications had to be applied: a stronger mainspring (which is shorter and has a thicker blade strength to optimally use the barrel space— 1/3 barrel, 1/3 barrel core, 1/3 free); and two additional jewel bearings had to be inserted with the help of an additional tourbillon bridge on the dial side of the movement that also supports the mainspring barrel.
The tourbillon itself is of classic flying construction. In the first implementation, it was fitted with ruby bearings for the (http://www.watchreplicahome.com/breitling-watches-navitimer-watches-c-17_141.html) balance axle. Ever the perfectionist, Gerber decided to change to a diamond cap jewel: A simple modification one might think, but that was not the case. The tourbillon top bridge had to be made a second time completely from scratch to take into account the now increased diameter of the diamond end stone: 1mm instead of 0.7mm of the ruby stone. Consequence: the two screws that fix the cap jewel plate had to move outward. That means the cap jewel plate as well as the entire top tourbillon bridge had to be redone. The construction of a new chronograph mechanism is quite a technical feat that very few manu-factures undertake. The broad use of the handful of commonly available chronograph calibers is ample evidence of this. A split-seconds chronograph is particularly challenging, many times more difficult than a simple chronograph even, because of the incredible tolerances that must be realized to keep from putting a critical strain on the (http://www.watchreplicahome.com/hublot-watches-big-bang-watches-c-36_251.html) movement when the chronograph is engaged and especially when the split-seconds mechanism is activated. The fine adjustment necessary and infinitesimal loads that must be balanced against each other make a rattrapante possibly the most challenging complication to properly
setup and adjust.
In this special case, the mountain of difficulties was two or three times higher than usual: An incredibly complicated movement, a unique piece, should be upgraded with a split-seconds flyback chrongraph, operated by a column wheel, of course. Challenging even more so because the gongs of the sonnerie and repeater were in the way of the (http://www.watchreplicahome.com/panerai-watches-luminor-watches-c-45_300.html) chronograph pushers. The existing beautiful dial should be used, which fixes the placement of the chronograph hands. Last but not least the movement should not gain much height, since that would make the use of the platinum case impossible. Is it any wonder this challenge kept a master watchmaker working for eight years?
Since the movement was not intended to be fitted with a time-counting mechanism, there was of course no space reserved for it. Forced to use every bit of space that could hold a wheel or a lever, Paul Gerber invented one of the most technically demanding chronograph mechanisms ever seen. In the end, a classical but uniquely implemented column wheel chronograph was the (http://www.watchreplicahome.com/cartier-watches-santos-watches-c-22_182.html) result of years of construction, testing, modification, further testing and finally approval. Several characteristics of this astounding mechanism should be covered more in detail.