Sometimes you need to display a number nice and large, making it easily readable at a good distance. [Lewis] has just the thing for that: a big expandable 7-segment display.
The build is modular, allowing it to be extended from 2 to 10 digits and beyond. The digits themselves are made of 3D-printed parts assembled onto acrylic. These can then be ganged up in a wooden frame for displaying larger numbers with more digits. Individual elements are lit by addressable LEDs, and the project can be built using an Arduino Nano or an ESP8266 for control. The latter opens up possibilities for controlling the screen over WiFi, which could prove useful.
[Lewis] has built his own version for a local swim club, where it will be used as a laptimer. Other applications could be as a scoreboard in various sports, or to confuse your neighbours by displaying random numbers in your front yard.
We’ve seen a similar build from [Ivan Miranda] that served well as a workshop clock, too. Video after the break.