Split-flap displays work by printing letters or numbers ... and uses an Arduino as the control board. A 3D printer and CNC machine keep the tolerances tight enough for the display to work smoothly ...

That seems to be what’s going on with this beautiful split-flap clock build by [Erich Styger ... The four displays are controlled by a single controller board, which houses an NXP K22FN512 ...

Also known as the Solari board, the split-flap board used to be found in thousands of airports and train stations across the world displaying travel information. But in recent years, they have ...