Use an ESP32 to Add Wi-Fi to Any 3D Printer
This mod will let you use an ESP32 to transfer G-code to your 3D printer via Wi-Fi.
Like CNC mills, plasma cutters, water jets, and many other machine tools, FFF (fused filament fabrication) 3D printers operate by following a set of instructions called G-code. Slicing software, like Cura, creates that G-code based on a 3D model and printer-specific parameters. A 3D printing G-code file describes each move the printer will make and many moves come together to form toolpaths that result in a 3D part. Most entry-level 3D printers require that the user copy the G-code file to a USB thumb drive or SD card, but this mod will let you use an ESP32 to transfer G-code to your 3D printer via Wi-Fi.
This mod should work on most 3D printer models that have control boards with accessible UART (Universal Asynchronous Receiver/Transmitter) ports. Almost all control boards have a UART port, but the printer will also need to run compatible firmware: Repetier, Marlin, Smoothieware, GRBL, or Reprap. If your printer doesn’t have a UART or runs proprietary firmware, this mod may not be possible. Jason Winfield demonstrated the mod on a Creality Ender 3 V2, which is one of the most popular models on the market today. It should also work with models from Prusa, Anycubic, ELEGOO, and many others. If you aren’t sure if your printer is compatible, you can find some more information on the ESP3D GitHub page.
Your computer will “drip feed” G-code commands to your 3D printer’s control board through an ESP32 development board, like the popular Wemos D1 Mini. The computer will see the ESP32 (connected via Wi-Fi) as a virtual COM port, which most slicers and G-code senders work with. After receiving a G-code command, the ESP32 will pass it to the 3D printer through the UART port on the control board. This will only require 3 wires: one for power, one for transmitting data, and one for receiving data. Your control board may have a UART serial connection header, or you might need to solder wires directly to the chip as Winfield did.
Winfield provides all of the instructions for configuring your ESP32 and your computer for this mod. After following those steps, you’ll be able to send G-code directly to your 3D printer over your Wi-Fi network.