This enclosure is designed for the Arduino UNO R4 WiFi Thermal PID Controller, a fully web‑based temperature‑control system that drives a heater through an SSR and reads temperature from either a DS18B20 or a MAX31856 thermocouple amplifier. The case brings all the electronics together into a clean, safe, and professional‑looking unit while keeping wiring organized and easy to service.

Inside the enclosure, you’ll find dedicated mounting points for the Arduino R4, the MAX31856 thermocouple board, and a solid‑state relay. Each cable path—power input, thermocouple lead, and heater wiring—has its own routed channel or harness point to keep everything tidy and reduce strain on connectors. A side USB access port with a removable cover lets you update firmware or upload new code without opening the case.

This project is aimed at makers who want more flexibility than off‑the‑shelf temperature controllers, which often cost around US $150 and offer limited customization. This system is intentionally bare‑bones in hardware, with the entire user interface delivered through a modern web dashboard. That approach keeps the build economical while giving you full control over the software. If you want physical buttons, screens, or indicators, you can add them—this enclosure and firmware are designed to grow with your ideas.

The controller can be accessed through its built‑in WiFi access point or by joining your home network. Thanks to multicast DNS (mDNS), you don’t need to know the IP address—just connect using its hostname. More technical details, firmware, and the full prompt‑driven development workflow are available on the GitHub project page:
https://github.com/zwitterion/R4-Thermal-Controller

All source files are included here:

• Fusion 360 model for easy modification

• STL files ready to print

• PrusaSlicer project files with tuned settings

This enclosure is ideal for DIY reflow ovens, chemistry labs, hot‑plate controllers, or any thermal process project powered by the Arduino R4 PID controller. It keeps your electronics protected, your wiring neat, and your build looking like a finished product rather than a prototype.

Parts Required

Screws

Main Components