Refinement of remontoire components. Seconds
drive, begin celestial train - April 2009
The remontoire cages were largely finished back in January 2008. However
the pillars, poising weights and their support bars, as well as the remontoire support
structures had yet to be refined and decorated. The final counter-sunk screw designs were
chosen and the remontoire components were machined to accept them. In the two photos below
the left component before countersunk drilling, the one on the right, after.
Here we see the row of countersunk screws. These are necessary in this
assembly since the dual remontoire slide past each other with little clearance between
them. The second photo shows the turned pillars which until now were plain cylindrical
Below an overview of one of the two remontoire. Next the outline drawings
of the remontoire support structures.
The support structures are milled out and the semi-finished articles at
The remontoire poising weights are now milled to shape. This design is
inspired by Jean Wagner as displayed in examples of his work in my collection. Next
are shots of the seconds drive taken from the remontoire output.
The seconds drive is delivered through a set of four wheels to get the
correct ratios. These four relatively large wheels that are up front of the clock will
move quite rapidly being one of many components to attract the attention of the viewer
(see video clip below). Notice the use of jeweled chatons throughout this movement train.
First photo is a close-up of the seconds output wheels against the
remontoire support structure. The next few shots show the completed time train. It is one
of the most complex I've seen for a single train coming in at 650 parts, 54 wheels. There
will be another few added with the minute and hour motion works.
B. now begins the fabrication of the celestial train as it will be between
the main movement plates. He first begins with a series of card board discs representing
the desired wheel diameters to see if they can be planted where they need to be without
spatial conflicts. Notice the mechanical and mathematical notations in red on the
The wheels are now cut and planted on the Plexiglas plates. Next this is
incorporated next to it's neighbor, the time train.
Here is the movement to date. The project is now about 30% finished.
Another front and rear shot of progress to date.
The movement to date compared with the revised movement design mockup.
While it may look like much more is finished than the estimated 30%, there is a myriad of
work left. There is all of the behind-the-dial-work as well as the orrery and the two
dozen complications. Then there is the polishing of all components, bluing of hundreds of
screws and then plating.
In the videos below B. has attached oversized dial hands to the seconds
output. Another hand is attached to the time train clutch which rotates once per hour and
in the rear is a small hand attached to the remontoire reload output. This shows how the
often and how much the chain is drawn up. The chain will be drawn in on each fly fan
release; every 15 seconds. The remontoire chain will released, that is the remontoire will
be tripping the celestial train once per minute. There should be a significant amount of
movement in this system.
The first thing one notices is the large recoil on the seconds hand.
Remember that recoil is a hallmark of the grasshopper escapement, the pendulum is fully
attached to the escapement - the exact opposite of what most escapements try to do in
horology, that is, to make the pendulum as detached from the escapement as possible.
Furthermore, the pendulums are a 2 second period instead of the normal one second; so the
seconds hand travels twice the distance for each tick if the clock thus magnifying the
recoil by two.