Wood Gear Clock

  • January 6, 2013

This clock was my first major woodworking project. I started working on it during my sophomore summer in college when I stuck around Boston to work as a research assistant.

Based off of Clayton Boyer’s original Inclination design, my version uses different materials and incorporates copper inlays on the frame.  The mechanical function of the clock remains unchanged.  What originally attracted me to this clock was the unique weight trolley that rolls down the side of the frame.  Whereas every other mechanical clock of this type has a simple hanging weight, Inclination was different than any other clock I had ever seen.  This peculiar mechanism and the clock’s lack of a face makes most people not realize that it is a clock until they take a second look.

Going through the process of building this clock forced me to think about how a mechanical clock actually worked.  What I learned is that the mechanism that makes this clock tick is fundamentally very simple and elegant.  The weight provides energy and the pendulum provides regulation.  Everything else is just there to transfer the energy and turn it into a recognizable form.

The key mechanism to all mechanical clocks is the escapement which translates the pendulum’s regular back and forth motion to a controlled rotational “tick tock” of the clock.  Inclination uses a very common deadbeat escapement seen at right.  The main wheel train gears down the regular ticking to move the minute hand around the clock precisely at a rate of once per hour.  A secondary train simply divides that movement by 12 to sweep the hour hand.  By adjusting the length of the pendulum, one can change the period of its movement and thus, the speed of the clock.

I chose this clock as my first woodworking project because in its basic form, it was already such a fantastic object.  This way, I wouldn’t feel as obligated to make the construction more difficult by adding my own artistic elements.  I think I still may have gotten carried away with the “complications.”

Making this clock was an incredible learning experience in various woodworking and metalworking skills.  I programmed and operated various CNC equipment made available to me through the shops at MIT.  A CNC lathe was employed to create the copper weights and a CNC laser cut the gears and escapement.  In order to create the copper inlays, I used an Omax waterjet for the positives and a laser cutter to produce router templates with a precise tool offset.  Once the templates were made, a router was used to cut out the negative for the copper to fit into.

Becoming typical of the projects that I find myself doing is a melding of sculptural form with mechanical purpose.  This clock fits perfectly in that mold.  I took the basic shape and function of Clayton’s clock and added my own stylistic elements.  To create the look I was searching for, I used mahogany instead of maple as the base wood and combined that with copper accents.  In each of the frame pieces, a copper starburst was inlayed.  Each of the protruding axles received custom copper cones and the lead weight used in the original design was replaced with CNC cut copper billets riding on copper wheels.  Curly maple hands were used to contrast the dark wood of the frame.