Prusa CORE One/+ MMU - Servo Driven Chamber Ventilation

To automatically open and close the Vent Cover on the Prusa CORE One/+ with MMU3, I added a servo which is connected via the Prusa “Hackerboard” to the Prusa CORE One/+. Via a GCODE the Vent Cover can be opened and closed during the print.

WARNING: This MOD is supplied as is and you build it at your own risk. I will NOT be responsible for any damage or injury to you or your property that may occur. 

Print Settings:

Core One/+ MMU3 Vent Cover and Servo Support

• 0.4mm Nozzle

• Material: Prusament PETG or better

• Print Settings: 0.2mm STRUCTURAL

• Layers and perimeters

  • Perimeters: 3

  • Seam Position: Nearest

Servo Horn

• 0.25mm Nozzle

• Material: Prusament PETG or better

• Print Settings: 0.12mm STRUCTURAL

• Layers and perimeters

  • Seam position: Nearest

• Infill

  • Fill density: 100%

  • Fill pattern: Rectilinear

• Skirt and brim:

  • Brim width: 5mm

Additional parts required:

• 1x Prusa CORE One - GPIO Enclosure (incl. 1x Prusa GPIO "Hackerboard" set)

• 1x BIFRC Servo Trigger Controller Module Enclosure (incl. 1x BIFRC Servo Trigger Controller Module 1)

• 1x Micro Analog Servo EMAX ES08MA II

• 1x Servo Extension Cable 60cm

• 2x Jumper Wire male-female 10cm

• 1x 2.54mm Pitch Pin Header 9 PIN

• 1x Push Rod 80mm

• 1x Brass Insert Nut M3x5

• 1x Screw DIN 912 M3x10

• 2x 2mm Cross Phillips Tapping Screw

• 1x USB Type C to 2 USB Type C Splitter (only needed if already a camera is installed, which needs power of the USB-C Plug of the printer)

• 1x USB Type C Cable 15cm

• 1x Double Sided Adhesive Tape (ca. 35.5cm x 25cm)

• 5x Mini Cable Winder Organizer

Assembly Instructions:

1. Buy and print all the required parts, as listed above

2. Install the Prusa GPIO “Hackerboard” set

   1. It is recommented to solder the Pitch Pin Header to the Prusa GPIO Hackerboard

3. Connect the Prusa GPIO Hackerboard with the BIFRC Servo Trigger Module with the two Jumper Wires (see wiring diagramm):

   1. PRUSA GPIO Hackerboard PIN GND (Ground) → BIFRC Servo Trigger Module Ⓖ (Ground) 

   2. PRUSA GPIO Hackerboard PIN 0 → BIFRC Servo Trigger Module ①

4. Connect the USB Type C to 2 USB Type C Splitter to the USB Type C Plug of the printer (if needed)

5. Connect the Cable of the Camera (it there is any) and the USB Type C Cable 15cm to the USB Type C to 2 USB Type C Splitter

6. Connect the USB Type C Cable 15cm to the BIFRC Servo Trigger Module (see wiring diagramm)

7. Put the Double Sided Adhesive Tape on the back of the Servo Support

8. Mount the Micro Analog Servo EMAX ES08MA II with two 2mm Cross Phillips tapping Screw to the Servo Support

9. Mount the Servo Horn to the Micro Analog Servo EMAX ES08MA II with the original Servo Screw

10. Mount the Brass Insert Nut M3x5 into the Core One MMU3 Vent Cover

11. Replace the original Core One MMU3 Vent Cover with Core One MMU3 Vent Cover (use the original M3x10Tr Screws (2x), Vent Nut (2x) and O-Rings(2x))

12. Tape the Servo Support to the MMU Top Cover

13. Mount the Push Rod 80mm to the Servo Horn and the Core One MMU3 Vent Cover

14. Add the Screw DIN 912 M3x10 to the Brass Insert Nut M3x5

15. Connect the Micro Analog Servo EMAX ES08MA II via the Servo Extension Cable 60cm to the BIFRC Servo Trigger Module

16. Align the Push Rod 80mm/Servo position correctly and tighten the Screw DIN 912 M3x10

17. Set the correct Mode on the BIFRC Servo Trigger Module

18. Perform a proper wiring, use the Mini Cable Winder Organizer

19. Add the following GCODE to your Prusa Slicer

GCODE that needs to be added to the "Start G-Code" Section in Prusa Slicer:

; Automatic Chamber Vent Control
{if filament_type[initial_tool] =~ /.*(PLA|PETG).*/}
M262 P0 B0
M264 P0 B1
{else}
M262 P0 B0
M264 P0 B0
{endif}

GCODE that needs to be added to the "End G-Code" Section in Prusa Slicer:

; Automatic close the Chamber Vent if it was opened
{if filament_type[initial_tool] =~ /.*(PLA|PETG).*/}
M264 P0 B0
{endif}