REMIX - Extruder Nozzle Cleaning System

thingiverse

This is a detailed guide on how to integrate a servo-controlled brush into a 3D printing setup using an Octoprint and a Raspberry Pi. The goal is to home the brush out of the way during prints and deploy it in front of the extruder for cleaning. ### Servo Trigger Setup 1. **Identify the Servo Trigger Version:** Before setting up the programming, test which version of servo trigger you have: * One responds to switch state changes (open or closed). * The other requires a cycle of the switch (off/on/off) to move the servo. 2. **Deploy the Brush:** Move the brush to its cleaning position over the print bed to determine the correct Z-axis height for the cleaning cycle, then home the brush back out of the way. ### LED Strip Control Plugin Setup 1. Install the LED Strip Control plugin on your Octoprint. 2. Configure it so that it only knows about the red pin (set it to physical pin 12 on the GPIO header). ### Startup Scripts Configuration In your slicer's startup scripts, add the following sequence of commands: - **For Servo Trigger Requiring a Cycle:** ```bash G28; # Home all axes G1 Z32 F1200; # Lift Z by 32mm for cleaning M150 R0; # Start brush deploy sequence G4 P500 M150 R255; G4 P500 M150 R0; G4 P500 # Cleaning passes G1 X335 F1200; # First scrub pass G1 X300 F1200; # Second scrub pass G1 X335 F1200; # Third scrub pass G1 X165 F1200; # Fourth scrub pass and move extruder back to center M150 R0; # Start brush home sequence G4 P500 M150 R255; G4 P500 M150 R0; G4 P500 M150 R0; G4 P500 M150 R255; G4 P500 M150 R0; G4 P500; # Complete brush home sequence ``` - **For Servo Trigger Requiring a State Change:** ```bash G28; # Home all axes G1 Z32 F1200; # Lift Z by 32mm for cleaning # Deploy the brush for cleaning M150 R0; # Set brush state to home G4 P500 M150 R255; G4 P500 # Cleaning passes # Add your scrubbing commands here, e.g., G1 X335 F1200; # Home the brush M150 R0; G4 P500 M150 R0; ``` ### Important Notes: - **Temperature Requirement:** The sequence MUST run after your extruder heats to printing temperature. - **Pause Commands (G4):** These commands are necessary for the servo trigger to read the switch states and should not be removed. They cause a 500 millisecond pause between each command, allowing time for the servo trigger to execute its actions. - **Responsibility:** This guide was developed after experiencing several extruder crashes into the brush. It is essential to stand by the printer during initial use and be prepared to stop it immediately if anything seems amiss to avoid damage. This setup allows for a controlled deployment of a brush for cleaning purposes, ensuring safety and preventing damage to your 3D printing equipment.