One can never have too many LEDs…but we won’t let that stop us from trying. This project brings together nearly 25,000 full-color LEDs in a mesmerizing, self-contained interactive cube, with the small-and-mighty Raspberry Pi 4 — the Altoids of computers — running the show. Possibly the most ostentatious project we’ve attempted!
The flowing pixel sand demo uses an accelerometer for a mesmerizing motion effect.
The grains of sand trickle down and move across all six panels making this physics toy unlike anything else.
IMPORTANT: We’ve assigned this guide a rare “Advanced” skill level recommendation. Not that it’s especially deep or technical, but we must admit it’s expensive. Most any day we would celebrate learning through rookie mistakes…but here, one mis-step like connecting the wrong power supply could ruin hundreds in parts. It’s best for folks who’ve cultivated patience and thoroughness through experience.
This build is also unusual in that it’s non-linear, with several steps cycling between 3D printing, soldering and wiring, and installing and testing code…it’s not simply one after the other. This is to allow testing and troubleshooting at the earliest opportunity, while everything’s out in the open, to help avoid lengthy setbacks later (see “patience and thoroughness through experience,” above). And starting with the 3D printing allows multitasking…you can get started while electronics are in transit, and do some initial board and code testing as printing gradually proceeds.
Before committing, skim through the guide to see what it all entails.
This is one of our most ambitious DIY projects, with a lot of big-ticket parts and fine tolerances, and you’ll want to take good care of it. The LED matrices are designed for digital signs and not really for handheld use. With rough handling, individual LEDs may get sheared off along the edges and corners. The rest of the matrix will still work, there will just be blank spots and you’ll be a little sad.
- Lift the cube with both hands flat against the faces, not along the edges. Gently pass it from flat palm to flat palm.
- Use something like a plastic spudger tool to carefully open the cube, do not claw at it with your fingers. A guitar pick or old credit or transit card can work just fine!
- Resist the overwhelming urge to spin the cube with fingers on opposite corners.
- Soldering iron and related paraphernalia. There’s very little soldering required, but non-zero.
- Basic maker tools like pliers and small screwdrivers (for DC power screw terminals).
- A plastic “spudger” tool for prying open the assembled cube, or a makeshift equivalent (guitar pick, old credit card), perhaps sanding one edge to better feed into narrow slots.