3D Printed Analog Clock

This is an analog watch for my desk. The brain of this clock is an Arduino Nano. Using 3 stepper motors we can rotate the hour, minute and second hand accordingly. All the movable parts are 3D Printed. The 3D files are linked below.

1. Arduino Nano
2. 28byj-48 unipolar stepper motor (3 pieces)
3. A4988 stepper motor driver (3 pieces)
4. Buzzer
5. Buttons (3 pieces)
6. 3D Printed Parts
7. Acrylic sheet

As I am using 28byj-48 stepper motors, which are unipolar, so you need to modify it to make it a bipolar stepper motor.

For that we need to open the plastic cover near the wiring and scratch the middle connection in the PCB. In this way we need to modify all the three motors.

All the transmission gears and the clock hands are 3D Printed. The 3D Files are attached below.

To simplify all the connections and to give a clean look to the project, I made a PCB.

Then solder all the components to the PCB. The connection diagram can be found below.

Here I am using an Arduino Nano as the brain of the project. In combination with three 28byj-48 stepper motor the clock works perfectly.

Attach the PCB to the acrylic sheet with some nuts and bolts. Then assemble the acrylic stand along with the 3D Printed part on both sides.

Using a 6 inch long screw, assemble the second, minute and hour gears to the rod. Then place the second, minute and hour hands onto the gear.

After the clock assembly is ready, the we need to calibrate the clock.

By adjusting the delay time, we can do that very easily. In my case, I set the second hand delay for 6 milliseconds, similarly for the minute hand 60 milliseconds and for the hour hand 600 milliseconds.

And BOOM, our clock is ready.