Riven is a motor driven wooden clock aimed at tearing apart traditional horological reduction methods. It is the first clock to use a system of dual stage hypocycloid reducers on a single shared rotation axis. With a design aesthetic inspired by tourbillons, Riven’s name applies also to its forms. For a brief moment at both noon and midnight, every gear, support, hand, and frame will align. An instant later, the forms split apart as each follows its own unique eccentric motion.


Suspended Hand

Through the use of ultra high pull neodymium magnets, Riven's minute hand appears to defy gravity as it slowly glides along the clock's perimeter. It circles 360 degrees without ever touching the parts that drive its movement.

Hypocycloid Reducers

Riven's reduction mechanisms are a unique and perplexing sort. They produce a complex and enthralling visual effect while at the same time allowing all of Riven's moving parts to share the same single axis of rotation. The reduction ratios of each of Riven's three dual stage hypocycloid reducers were calculated with dsHypoGen, a software tool created specifically to aid in developing Riven.

Automatic Clutch Fuse

To help protect the motor from being mechanically overloaded, a magnetic mechanical combination clutch and fuse is utilized. If any parts bind, or if the clock demands too much torque, two magnets split apart from each other, decoupling the motor from the rest of the drive train. A few seconds after separating, the mechanism automatically attempts to reconnect and reengage.

Set Seamlessly

Hypocycloid reducers are not back-drivable, which created a challenging design problem in being able to set Riven's time. The solution to this problem lied in enabling the clock's final reduction stage to tightly grab (but not lock) onto its input shaft. This non-locking feature allows the clock's time to be set simply by turning the part magnetizing the minute hand. Riven's hand positions can be set at any time, even while the motor is running.

Run Time
Continuous (motor driven)

Woodworking Plans
42 pages 8.5" x 11"
6 pages
11" x 17"
48 pages

24 DXF files

Free Downloads



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