Prusa i3 MK3s R4 extruder MMU2s with path through coupling and second tensioner

thingiverse

Extruder assembly optimized for Prusa MK3S/MMU2S, featuring a streamlined path through the FESTO coupling PC4-01. Enhanced filament feed and reduced vibration result from integrating the filament entry directly into the extruder motor plate, eliminating the need for additional accessories such as the FS cover-MMU2S or printer adapter-MMU2S. A conveniently attached Ir sensor holder securely fastens to one side of the extruder motor plate, allowing for easy adjustments using washers on this attachment point. Optional modifications include a modified X-carriage and an optional extruder cover with an additional bottom attachment. This upgrade also addresses noise issues generated by the Bondtech gears during filament change processes on the MK3S/MMU2S. A second tensioner screw is added to re-center pressure along the filament path, ensuring optimal performance. Note: To achieve best results, use previous MK3 extruder tension springs (soft), avoiding mixing with the harder MK3S single spring.