A very common challenge when working with any kind of networked “headless” project is configuring the network adapter to connect to your WiFi. It’s easy enough to enter your credentials when you first program your development board or setup your single-board computer. The difficulty arises when you change your network name or password, or when you decide to take the device with you somewhere and have to connect to a new network. One of the best solutions is to have the device create its own hotspot when it isn’t connected to a network, so you can enter the credentials remotely. Ivan Miranda’s new gigantic 3D-printed LED clock utilizes that solution and looks great doing it.
Miranda already had a relatively big WiFi-connected clock in his workshop, but found himself frustrated when he ran into router trouble and had to reprogram the clock with new credentials. He decided to address the shortcomings of the old clock and figured he might as well go all-out and build an entirely new clock while he was at it. This new clock is absolutely massive—several times larger than the original design. Other than the electronic components and a few screws, everything is completely 3D-printed. That includes the light diffusers used to keep the LEDs from producing bright spots and the internal frames used to hold the components securely in place.
The numerical digits on the time readout look like the seven-segment displays so common to digital clocks, but each segment is actually lit by several LEDs. Those are WS2812B individually-addressable RGB LEDs, which dramatically simplifies the wiring and makes it easy to change the color or to program animated effects. The LEDs are controlled by an ESP8266 NodeMCU board. That pulls the time from an NIST server via WiFi. The NodeMCU board is programmed to automatically switch to providing its own WiFi hotspot if it loses a network connection, which makes it easy to enter new WiFi credentials when necessary.