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This project is about building a stepper motor clock around the NXP LPC845-BRK board. The design is using a combination of 3D printed and laser cut parts and costs below $15.

The GitHub repository (see links at the end of the article) includes an Excel file with the Bill-Of-Material (BOM). You need

NXP MUCXpresso IDE (I have used the V11.0.0)
NXP LPC845-BRK board
2 28BYJ-48 5V Stepper Motors with ULN2003 driver
2 Neodymium magnets (e.g. 5x2mm)
Realtime clock with battery (DS3231)
2 Bearings 10x15x4mm
2 hall sensors (AH3572)
Strand wires
12 M3 nuts and bolts
8 small (2×10 mm) wood
Shrink-wrap tubing
Soldering station and a few extra wires for power connection
Plywood or PMMA/Acrylic material and access to a laser cutter
Access to a 3D printer (I used an Ultimaker 2 with white PLA material)
Optional: OpenSCAD to change the gears
Optional: 3D modelling software to change the 3D models (I used 123Design from AutoDesc)
Optional: wireless charging receiver module and charging station (see links at the end of the article for options)
The clock is designed around the very inexpensive 28BYJ-48 stepper motors (you can get 5 of them including the stepper motor driver board for less than $10).

The idea is to use the two stepper motors to driver each clock hand using a simple gear. the motors are placed in reverse to minimize space. The gears with shaft are 3D printed.”

Link to article