Retractable Nozzle Cleaning Brush for Voron 2.4 350

Voron Nozzle Brush – Servo Driven Mechanism

This project is a simple mechanical nozzle cleaning system for Voron printers. It uses a small tray with a brass brush that is moved in and out of the print area using a lever mechanism powered by a micro servo.

Features

- Compact brush holder mounted on standard Voron extrusion

- Lever mechanism keeps the brush level during movement

- Servo-powered deployment and retraction

- Power switching for the servo to prevent jitter and overheating

- Fully compatible with Klipper macros

Hardware Setup

- Servo: 9g micro servo (tested with Goteck GS-D9025MG)

- Power: +5V via step-down converter

- Control board: BTT Octopus (pins must be adjusted for your setup)

Wiring:

- +5V → from PSU via step-down

- GND → switched via MOSFET (fan output)

- Signal → any free GPIO pin

This allows the servo to be powered only when needed .

Printing Settings

- Material: ASA (recommended for enclosed printers)

- Layer height: 0.2 mm

- Infill: 40%

- Perimeters: 4

- Nozzle: 0.4 mm

- Supports: only where necessary

Increase infill for mechanical parts (arms, servo mount).

Assembly Notes

- Install all heat-set inserts before assembly

- Set servo position before mounting arms

- Make sure the brush stays level during motion

- Check all clearances (bed / nozzle collision)

- Trim carbon rods or pins so they don’t protrude

Klipper Macros

Below is a working example of the brush control and cleaning macro:

# --- BRUSH MACROS ---

[gcode_macro _BRUSH_STATE] variable_deployed: 0 variable_saved_temp: 0 gcode:

[gcode_macro _ENSURE_BRUSH_RETRACTED] gcode: {% if printer["gcode_macro _BRUSH_STATE"].deployed == 1 %} BRUSH_OUT {% endif %}

[servo nozzle_brush] pin: PA15 maximum_servo_angle: 180 minimum_pulse_width: 0.0005 maximum_pulse_width: 0.0025

[output_pin servo_power] pin: PD15 pwm: False value: 0 shutdown_value: 0

[gcode_macro BRUSH_OUT] description: Move brush to the safe retracted position gcode: SET_PIN PIN=servo_power VALUE=1 G4 P300 SET_SERVO SERVO=nozzle_brush ANGLE=45 G4 P600 SET_SERVO SERVO=nozzle_brush WIDTH=0 G4 P200 SET_GCODE_VARIABLE MACRO=_BRUSH_STATE VARIABLE=deployed VALUE=1

[gcode_macro BRUSH_IN] description: Move brush to the active wipe position gcode: SET_PIN PIN=servo_power VALUE=1 G4 P300 SET_SERVO SERVO=nozzle_brush ANGLE=132 G4 P600 SET_SERVO SERVO=nozzle_brush WIDTH=0 G4 P200 SET_PIN PIN=servo_power VALUE=0 SET_GCODE_VARIABLE MACRO=_BRUSH_STATE VARIABLE=deployed VALUE=0