Elegoo CC2 top rear spool holder | TPU printing

I needed a top-rear mounted spool holder as my TPU was dragged too hard from the default location of the CC2 (not combo). I found the mentioned original model but that mounts to the left side of the printer and I only have space on the back, it also prints the spool holder which takes time and filament.

I used the idea and the hook profile of the original model to make something similar in FreeCAD that uses the stock spool holder with a 3D printed connector that I can attach with two M3 screws and nuts (I had 15mm long ones).

Added modifiers in FreeCAD so they can be easily modified in the slicer. The hexagonal pattern is created in the slicer using a trick (credits to @MangoJellySolutions). The other modifier is used to create 100% infills where I think it adds to structural strength.

The FreeCAD file is included, not my best organized project but naming should be obvious and easy to understand. I am only a beginner in CAD so mistakes and problems in the model may exist.

Included two 3MF files (the original that I printed and use, the updated with better naming and better screw and nut holes as they were a bit tight). 3MF configured for the CC2 with hopefully my calilbrated PETG Pro and slicer profiles included in the project (feel free to use your own settings). If the modifiers are not modifying when sliced, change object type to modifier in the objects tab.

Print time was 4h52m and used 115g of filament.

Settings I used to print:

• Printer: Elegoo Centauri Carbon 2

• Filament: Elegoo PETG Pro Gray

• Layer height: 0.25

• Wall loops: 3

• Top and bottom shell layers: 5 and 4 respectively

• Infill density: 25%

• Infill pattern: 3D honeycomb

• Support: not needed, oriented correctly

• Skirt loops: 2, height 1 (I use it to clean the nozzle and see leveling errors)

• Brim type: mouse ear/auto (I used none and it started to warp under the hook, fortunately I adjusted Z height offset mid-print and came out almost perfect with only a visual defect)

Hexagonal pattern modifier (feel free to experiment with it):

• Infill density: 15%

• Wall loops: 2

• Top and bottom shell layers: 0

• Fill multiline: 3

• Infill pattern: honeycomb

• Infill direction: 135° (adjusted in the updated version)

• Filter out tiny gaps: 10mm (not sure if helps or not)

• Infill/wall overlap (important for strength): 60%

Strong infill modifier:

• Sparse infill density: 30%

• Wall loops: 5

The spool connector (by jasonfantastic) was printed on its side to increase strength with 100% infill, with organic supports for the holes. This also increased print time from 20 minutes to 40.

As my TPU is on a cardboard spool I printed this low-friction insert (by Thalaniel) so the TPU doesn't stretch when pulled.

A piece of teflon tube (about 8cm) was added to the printhead to reduce drag.

I am working on an updated design, hopefully reducing print time and lowering center of mass.