Jan Nieber

Overview: Why Modify the Gaggia Classic? Standard home espresso machines like the Gaggia Classic Pro offer solid builds but lack the granular control found in high-end commercial units. The Gaggimate project, developed by Jan Nieber, aims to bridge this gap. By integrating a custom PCB and software, this modification adds PID temperature control, Bluetooth scale connectivity, and automated pre-infusion. It matters because it brings expensive features like brewing by weight and thermal stability to a budget-friendly platform, all while maintaining an open-source spirit under Creative Commons licensing. Prerequisites: Essential Hardware and Concepts Before cracking open your machine, you must understand high-voltage safety and basic circuitry. You are working with 110V/220V mains power; unplugging the machine is non-negotiable. Familiarity with JST connectors and wire crimping is required for the low-voltage logic side. You should also understand the function of a Solid State Relay (SSR), which allows the low-power microcontroller to switch the high-power heating elements. Key Libraries & Tools * **Gaggimate PCB**: The brain of the operation, featuring an ESP32 or similar microcontroller with built-in Wi-Fi and Bluetooth. * **Custom Firmware**: The open-source code managing PID loops and the touch-screen interface. * **SSR Unit**: Handles the heavy lifting of switching the boiler's power. * **Thermocouple Probe**: Replaces the stock thermostat to provide real-time temperature telemetry. * **Crimping Tool**: Necessary for securing wires into the JST and spade connectors. Code Walkthrough: Logical Implementation While the firmware is pre-compiled for most users, the logic follows a specific sequence. First, the system initializes the Wi-Fi stack for OTA (Over-The-Air) updates. ```python Pseudocode for Temperature Management if current_temp < target_temp - threshold: ssr_state(HIGH) # Full power to boiler elif current_temp >= target_temp: ssr_state(LOW) # Cut power to avoid overshoot ``` The UI loop handles the circular touch display, translating touch coordinates into commands for the pump and solenoid. The "Brew by Weight" logic listens for Bluetooth packets from a paired Acaia scale, triggering the solenoid to close the 3-way valve once the target mass is reached. Syntax Notes: Connectivity and UI The modification uses a local web interface accessible via `gaggimate.local`. This allows for "Lego-style" configuration without rewriting core C++ code. The GUI employs a circular design pattern, a refreshing departure from the rectangular displays seen on the Gaggiuino project. Practical Examples: Brewing Scenarios * **The Blooming Shot**: Configure a 3-second fill, a 10-second soak (pre-infusion), and a full pressure ramp. * **Steam Mode Conversion**: One swipe on the display reconfigures the PID target to steam temperatures, bypassing the need for manual thermostat cycling. Tips & Gotchas: Avoiding Common Pitfalls Fatigue and