That’s the ticket! He’s using a DS3231 RTC chip, which at +/- 2ppm 32.768kHz is more than precise enough. Some math, programming, and soldering later and the display is complete!

Using an Arduino Mega, DS3231 Real Time Clock Module, Eight stepper motors 28BYJ-48 with ULN2003 Driver, 82 cm Wooden strip 19x19mm, Steel Wire 1m, 46 Washer head screw 4.2 x 14 mm, 16 Button head ...

A square IPS LCD display is used to display an analog-style watch face, and time is kept by a DS3231 real-time clock. A pair of small vibration sensors are used to wake the watch when the user ...