A great project by Brian Obudho on all3dp.com goes through the build of an analog clock with a 3D printed case and special insides & software.

This DIY clock takes after grandma’s in a number of ways. For example, assuming you follow the instructions to the T, the case should be printed using wood and copper PLA. Apart from that, all of the inner workings are just like those found in grandma’s clock.

The digital insides consist of an Adafruit ESP32 Feather, a stepper motor, driver & battery.

The software is special: the clock corrects itself via software and an Internet connection to a NTP clock server!

At regular intervals, the software will poll the NTP clock server, and the time received – from the NTP server – is recorded in the ESP32 clock. Whenever it’s 12:00 (either noon or midnight) and the clock happens to be off for any reason, the software will fast-forward the hands to the 12 o’clock position, from which point the clock will resume its operation.

You can grab the 3D STL files via GitHub and go through the build on all3dp.com. Great work!