Filament Sensors
RatOS supports multiple sensor types that are toolhead-aware. These sensors can be combined to work together. Configure them as described - no other changes are needed.
When combining toolhead and bowden sensors, each sensor has a specific function. The toolhead sensor handles insert detection while the bowden sensor is responsible for runout detection. This has the benefit that you don't need to open a heated chamber and remove the bowden tube to remove old filament - it will be ejected and can be easily removed at the end of the bowden tube.
Sensors can be temporarily deactivated in the Mainsail user interface.
If a sensor shows "detected" when no filament is loaded and "empty" when filament is loaded, invert the switch_pin by adding or removing a ! in front of the pin name. The sensor state will be displayed in the Mainsail user interface.
Supported Sensors
RatOS Configuration
Toolhead Filament Sensor
Toolhead filament sensors attach directly to the toolhead.
Features
- Runout detection
- Insert detection
- Automatic filament loading on insert
- Automatic filament unloading after runout
- Automatic print resume after insert
- Spool joining for IDEX printers
- Filament grabbing on insert
- Filament presence/runout check before starting a print
- Frontend toolhead color status display
Configuration
[filament_switch_sensor toolhead_filament_sensor_t0]
pause_on_runout: False
event_delay: 0.1
switch_pin: ^!toolboard_t0:PB3
runout_gcode:
_ON_TOOLHEAD_FILAMENT_SENSOR_RUNOUT TOOLHEAD=0
insert_gcode:
_ON_TOOLHEAD_FILAMENT_SENSOR_INSERT TOOLHEAD=0
Bowden Filament Sensor
Bowden filament sensors attach somewhere along the bowden tube.
Features
- Runout detection
- Insert detection (no automatic action available, macro can be overridden)
- Automatic filament unloading after runout
- Spool joining for IDEX printers
- Filament presence/runout check before starting a print
- Frontend toolhead color status display
Configuration
[filament_switch_sensor bowden_filament_sensor_t0]
pause_on_runout: False
event_delay: 0.1
switch_pin: ^!PC15
runout_gcode:
_ON_BOWDEN_FILAMENT_SENSOR_RUNOUT TOOLHEAD=0
insert_gcode:
_ON_BOWDEN_FILAMENT_SENSOR_INSERT TOOLHEAD=0
Motion Filament Sensor
Motion sensors can detect filament clogs.
Features
- Optional runout detection
- Optional insert detection (no automatic action available, macro can be overridden)
- Clog detection
- Automatic filament unloading after runout
- Spool joining for IDEX printers
Configuration
[filament_motion_sensor bowden_filament_clog_t0]
switch_pin: ^PG15
detection_length: 8
extruder: extruder # extruder for T0, extruder1 for T1
pause_on_runout: False
event_delay: 3.0
pause_delay: 0.5
runout_gcode:
_ON_BOWDEN_FILAMENT_SENSOR_CLOG TOOLHEAD=0
insert_gcode:
Action Button
Some filament sensors, like the Orbiter filament sensor, come with an action button.
Features
- Filament unload
Configuration
[gcode_button toolhead_filament_sensor_button_t0]
pin: ^!toolboard_t0:PB4
release_gcode:
_ON_FILAMENT_SENSOR_BUTTON_PRESSED TOOLHEAD=0
press_gcode:
Orbiter Smart Filament Sensor example configuration
The new Orbiter Smart Filament Sensor with filament tangle detection.
[filament_switch_sensor toolhead_filament_sensor_t0]
pause_on_runout: False
event_delay: 0.1
switch_pin: ^PA13
runout_gcode:
_ON_TOOLHEAD_FILAMENT_SENSOR_RUNOUT TOOLHEAD=0
insert_gcode:
_ON_TOOLHEAD_FILAMENT_SENSOR_INSERT TOOLHEAD=0
[gcode_button toolhead_filament_sensor_button_t0]
pin: ^PA14
release_gcode:
{% if (printer.print_stats.state == "printing") %}
_ON_TOOLHEAD_FILAMENT_SENSOR_CLOG TOOLHEAD=0
{% else %}
_ON_FILAMENT_SENSOR_BUTTON_PRESSED TOOLHEAD=0
{% endif %}
press_gcode:
RatOS Configuration
Sensor features
[gcode_macro T0]
variable_enable_insert_detection: True # enables the insert detection
variable_enable_runout_detection: True # enables the runout detection
variable_enable_clog_detection: True # enables the clog detection
variable_unload_after_runout: True # unload filament after runout has been detected
variable_resume_after_insert: True # resumes the print after inserting new filament
Filament grabbing
When inserting a filament into the toolhead filament sensor, the extruder gears will grab the filament, even if the hotend is still cold.
[gcode_macro T0]
variable_filament_grabbing_speed: 1 # filament grabbing speed in mm/s
variable_filament_grabbing_length: 5 # filament grabbing length in mm
Purging
[gcode_macro T0]
variable_purge_after_load: 30 # purge x mm after the filament has been loaded to the nozzle tip
variable_purge_before_unload: 0 # purge x mm before the filament unloads
Feedrates
[gcode_macro T0]
variable_filament_load_speed: 10 # filament nozzle loading speed
variable_extruder_load_speed: 60 # extruder/cooling zone loading speed
Retraction
[gcode_macro PAUSE]
variable_retract: 1.5 # retract on pause print
variable_extrude: 1.5 # extrude before resume print
Parking Position
[gcode_macro RatOS]
variable_runout_park_in: "front" # back|front|center = gantry parking position if a runout or clog has been detected
variable_runout_park_x: 50 # float = if configured the x position of the toolhead. if not configured it will park in the middle
Advanced
[gcode_macro T0]
variable_cooling_position_to_nozzle_distance: 40 # distance between the cooling position and the nozzle
variable_tooolhead_sensor_to_extruder_gear_distance: 15 # distance between the filament sensor trigger point
# and where the filament hits the extruder gears
variable_extruder_gear_to_cooling_position_distance: 30 # distance between the extruder gears and the center of the heatsink cooling tube
variable_filament_loading_nozzle_offset: -10 # offset tuning value. positive or negative number.
# different nozzles can lead to too much or not enough extrusion while loading the filament