Pong Ball Display

thingiverse

These are the files used to create a stunning ping-pong ball display! This project is geared towards experienced makers who possess some technical knowledge and access to various tools. It streamlines other designs by using large, 3D printed parts to hold the diffusers, custom PCBs for precise spacing, and a laser-cut back plane for effortless assembly. <h1>Materials Needed:</h1> * 20 PCBs - I sourced mine from JLCPCB, which offered 30 boards for $9.30 * 128 5050 SMD LEDs that use the standard data format; I chose SK6812's for true white and purchased 1000 of them on eBay for $80, utilizing approximately $10 worth for this project; I recommend buying extra * 128 38mm ping (or beer) pong balls made from plastic to prevent flammability; read reviews if users complain about poor bounce quality - they're perfect for this! ($15 on eBay) * 40 M3x4 hex screws (~$5) * Wire * Arduino Uno or preferred µController * RTC Module, if necessary - I repurposed an old Adafruit D1307 (~$8) * 5V 10A power supply (Alitove, Amazon, $20) * Approximately 3Kg of filament (~$60) * 36"x24" Acrylic sheet (~$10) The total cost is approximately $165. <h1>PCB Assembly:</h1> Assemble the PCBs, installing them and wiring them up; consider having JLCPCB assemble them for you. Test each strip of LEDs before installation to ensure proper function. Some build tips: * Inspect each LED strip before assembly to prevent defective connections * The ground pin is the most challenging to solder - a bad connection may cause data errors after an affected LED * Cut the PCBs along the lines to create shorter strips for the shorter diagonals; use a band saw or coping saw * Wire power in 5 groups of four strips to avoid excessive current in a single wire * Double up wires in some holes for added stability * Install PCBs on the backplane before wiring <h1>Diffuser Panel:</h1> Print at any settings - rough is acceptable. Insert balls into diffusers before cutting; this ensures they hold pressure. Each ball has a seam, best kept hidden. Cut a hole at the bottom of each ball using a sharp hobby knife. Once cut, balls will dent easily, so handle with care. <h1>Frame Assembly:</h1> Print the frame in four pieces, mirroring two for added stability. I printed mine in four pieces, but consider replacing with wood for a more visually appealing finish. Be cautious of warping on corners. <h1>Electronics:</h1> I used an Arduino Uno due to availability, but an ESP32 or similar µController would be ideal for this project. The DC power supply comes with a barrel-jack-screw-terminal adapter; create a small PCB that distributes power and holds the RTC module. This setup puts both barrel jacks side by side. The uploaded code is basic and displays time; it's more or less commented. I will upload better code if I ever write it, but feel free to remix this project with improved code. I use VScode + PIO for uploading, but Arduino Studio should also work. <h1>Known Issues:</h1> Please let me know any questions, concerns, or necessary information I may have missed. I'll assist where possible.