Since I was already planning on modifying my V0.1, I also opted to do the Umbilical mod. This would simplify the wiring to the toolhead and not as intrusive as I was already doing other mods.

Sourcing Parts

I sourced the PCBs and wire from AliExpress.


I printed the following STLs from the repository.

  • FramePCBCover.STL
  • PTFE_Guide.stl
  • ToolheadSpacer_with_StrainRelief.STL

Printed parts

I also printed RyanDam’s cable management duct as my old one had broken tabs.


I referenced Maple Leaf Makers’ video for assembly.

First, I removed the old cable sleeve and zip ties. Then, I replaced the strain relief with the 3D printed part and the PCB.

PCB with strain relief

PCB with strain relief

I started cutting and crimping the toolhead cables into JST connectors. It was time consuming as my wire strippers weren’t that small and my crimper was finicky.

Crimped JST cables

Crimped JST cables

I then crimped the cables connecting to the main board.

After finishing the crimps, I installed the frame PCB and cover. Since I used ferrules instead of bare wire for the heater, it wouldn’t sit flush against the motor. I ended up using a M3x12 BHCS with four nuts to act as spacers.

All that was left to do was install the PTFE guide near frame PCB and the umbilical cable.

PTFE guide

PTFE guide


After booting up the printer, I tested out the following:

  • Hotend heater
  • Hotend fan
  • Hotend thermistor
  • Parts fans
  • X endstop
  • Extruder motor

Everything except the parts fans seemed to work, so I needed to find the problem. The parts fan had a single connector. I spliced the cable three times, one to lengthen and twice to merge the two fans into one cable.

I noticed that the direction of the extruder motor switched, so I changed it in printer.cfg.

I checked the continuity of the cables and found that the polarity was swapped. I’m not sure why since I always connected red to red, but swapping it fixed the problem.


Overall, this was a very painful mod. The cables were small and JST connectors were finicky. But, the wiring looks nicer and it should make future toolhead changes easier.

Rear view