Fan Dial (Sector Dial) Clock – 3D Printed Clock with Geneva Wheel Mechanism

This project is inspired by historical sector (fan) dial clocks, where time is displayed on a curved arc instead of a full 360° dial. The minute indicator sweeps across the fan-shaped scale, offering an alternative and visually engaging way to read time.

At the core of the design is a Geneva wheel mechanism, used to index the motion of the indicator. The Geneva mechanism converts continuous rotation into discrete, step-by-step movement, making the clock especially interesting from a mechanical, educational, and kinematic perspective. This mechanism was a key part of the design process and strongly influenced the final form of the clock.

The construction is optimized for FDM 3D printing, with clearly separated parts and no complex supports. The open layout allows easy observation of how motion is transferred through the mechanism, making the model suitable for learning, experimentation, and display.

The clock can be hanged on the wall as well.

This project is ideal for makers interested in alternative time displays, Geneva mechanisms, and visible mechanical systems.

Take a look on this video to see how it works:
https://youtube.com/watch?v=WOyvPPddY4A&feature=shared

Clock with stand is about 30 cm high.

Design Highlights

• Sector (fan) dial time display

• Geneva wheel indexing mechanism

• Exposed mechanical elements

• Optimized for FDM printers

• Modular design, easy to modify

Printing settings

• Some parts should be printed with supports - it's indicated in file name.

• Part 'minutes' should be glued to 'dial plate' via 'minutes connector".
  

• Detailed assembly instructions coming soon :)

Requirements

• 2 × large bearings 6000zz (26 × 10 × 8 mm)

• 3 × small bearings MR 115zz (11 × 4 × 5 mm)

• High Torque (!) quartz clock mechanism

• Some glue and 2,5-3 mm screws

Important Note

A High Torque quartz mechanism is required to drive the entire project.
The clock is based on mounting the Quartz gear (20) directly onto the minute shaft of the quartz mechanism.

Please note that quartz mechanisms differ in minute shaft length and hand mounting dimensions.
The mechanism used in this project and the exact position of the gear mounting are shown in the reference images.

To make adaptation easier, the Quartz gear (20) is also included as a STEP file and can be edited to fit your specific mechanism.

If you are unable to edit the model, please send me the following measurements at [email protected]:

• minute shaft length

• minute hand mounting dimensions

I will prepare a version of the part adjusted specifically for your quartz mechanism.