DIY split-flap display by Scott Bezek


This is a work in progress split-flap display. Each module can flip between 40 unique characters: letters, numbers, and a few symbols. Multiple modules fit perfectly alongside each other to build bigger displays.

The primary design goal was to make something that's possible to fabricate at home in small or single quantities and can be customized and built by an intermediate hobbyist at a reasonable price. This meant using widely available materials and avoiding any tooling with a high upfront cost.

Following that philosophy, the design uses store-bought vinyl stickers for the letters, is driven by an ubiquitous and cheap 28BYJ-48 stepper motor, and uses common PVC ID badge cards cut to shape for the flaps (though custom die-cut flaps are also available). Even the enclosure, spool, and gears, which are all made from laser-cut MDF, can be easily ordered online.

This design is currently nearly stable. The source code in the git repo has been used to produce several working prototypes, and the v0.5 design is stable enough to have fairly comprehensive Ordering Instructions and an Assembly Guide. Of course, as this is an open source side-project, you may still come across minor issues or missing documentation.

Open source, up to date

All of the designs are open source. The 3d model is built using OpenSCAD, the driver electronics board is designed in KiCad, and the driver firmware is written using Arduino.

Most of the supporting materials, like the schematic, bill of materials, PCB gerbers, and even the interactive 3D rendering seen above are generated automatically as the design changes, using Github Actions. This way you can always see the latest designs, even without having to check out the git repo or install any software yourself.

I'd love to hear your thoughts and questions about this project, and happy to incorporate any feedback you might have into these designs! Please feel free (and encouraged) to open GitHub issues, email me directly, reach out on Twitter, and get involved in the open source development and let's keep chatting and building together!


This project is licensed under Apache v2 (see LICENSE.txt for full details).

Copyright 2015-2021 Scott Bezek and the splitflap contributors

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at


Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
See the License for the specific language governing permissions and
limitations under the License.