Core One MMU3 Y-Splitter using E3D V6 Collets mountable on Swing Arm

Core One MMU3 Y-Splitter using E3D V6 Collets, mountable on the Swing Arm.

There is also a Y-Splitter with Bowden collets available if no E3D V6 collets are available.

Changes 27. October 2025: Removed old files (obsolete), added step file.

Improvement 31. July 2025: Widened the inner tubes to 2.5mm to better retract the filament into the MMU3. Use the streight path for the MMU3 tube for smoother function.

This Y-Splitter is intended to be used when a MMU3 is mounted on the Core One and the right side Spool should still be usable as an alternative path.

Additional material requirements:

3 x E3D V6 collets, the same as used on the original MMU3 buffer

Printing recommendation:

upright printing with no supports, use PETG filament

0.4 nozzle, 0.2 structural, 4 perimeters, 20% infill gyroid, brim

Mounting recommendation:

Switch off the printer power.

Put an E3D V6 collet into every inlet of the Y-splitter

The Y splitter can be mounted with the velcros, but it is designed to be mounted with the swing arm brackets.

Attach it between the leftmost and middle mount point on the swing arm.

Slide the swing arm all the way back. Hold the PTFE tube coming from the right spool against the right dual PTFE tube inlet of the splitter. Make sure the tube is still properly bent. Mark the edge of the splitter on the tube and cut it 8 mm longer than marked. Push the tube into the front inlet (curved path).

Now slide the Nextruder to the front left. Push the second section of the PTFE tube into the left side of the splitter and secure it to the cable every 6 cm using velcro fasteners or a bracket. Slip the Bowden bend over the tube and hold it against the Nextruder inlet. The tube should be slightly curved, running over the Nextruder's cable bracket. Cut the PTFE tube 15 mm beyond the Bowden bend. Attach the tube to the Nextruder and push the Bowden bend down.

Now install the PTFE tube from the MMU3 output to the right second inlet (streight path) on the splitter, let enough length that the tube can move free when the MMU3 changes position between 1 and 5. 

The needed PTFE tube lenght depends on the mounting position of the MMU3.

Below a few pictures to view the a sample for the PTFE tube routing:

Switch the printer on and enjoy printing.