Ender 3 V3 CoreXZ Willys the Ultimate Top Spool Holder

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UPDATE 2025/07/20:

A filament runout sensor holder accessory for the Willyz top spool holder is added.

It connects the spool holder from the back accessory section. 
It allows you to connect the filament directly to the extruder header without a Teflon tube.

It consists of two parts: a connection arm and the sensor holder part. 
You can connect the two parts by hand screwing, or you can use a flathead screwdriver for your convenience. 
Just do not over-tighten the screw, it is just mere printed plastics, be gentle (!)

Use the original M3 screws to connect the filament runout sensor to the holder part. 
Check the added photo for instructions on how to add the arm to the spool holder.  

The filament runout sensor cable needs to be extended. 

I used an existing 42cm 3-pin PWM fan power extension cable from my pc parts. I cut the original filament sensor cable at the center, cropped the two headers of the fan extension cable, added heat shrink tubes beforehand, and soldered the PWM extension cable in the middle of the two cut parts of the original filament sensor cable. See the related photo for the final result.

I am giving some links as a reference point. You can try to find a ready-to-use cable if you don't want to mess with your cable; your cable, your choice.

https://www.aliexpress.com/item/1005006869041124.html       3 pin pwm fan power extension cable

https://www.aliexpress.com/item/1005003656072716.html       3 pin multicore black awg26 cable

https://www.aliexpress.com/item/1005008945322340.html       Heatshrink Tube

You can route the cable between the two halves of the spool holder, as shown in the added photo. 

Feedbacks are appreciated. 

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Willys is the ultimate top spool holder for Ender3 V3 CoreXZ.

You can use the original spool holder parts and the screw. Please check the photos for the details.

The base part is designed to fit exactly with the original spool holder that came with the printer. Hopefully, Creality uses the same mold for all the spool holders that came with Ender 3 v3 printers.

For a single spool holder, print and prepare the following:
1- spool_holder_base.stl
2- spool_holder_face.stl
3- spool_holder_face_pinnerSTL (use this part to connect and glue the two parts of the face model)
4- filament_guide_single.stl
5-
For a stable working top spool holder, I suggest you use this design
https://www.printables.com/model/1013979-ender3-spool-holder

For the double spool holder, please print the following models:
1. spool_holder_base.stl
2. spool_holder_face.stl
3. spool_holder_face_pinnerSTL (use this part to connect and glue the two parts of the face model)
4. filament_guide_back.stl and filament_guide_front.stl (I am not sure why I designed two different parts for the same job, but you can mirror print the back part for frontal usage, I suppose)
5. double spool_holder_main.stl, double spool_holder_dual.stl, and spool_screw_3.stl (I modified 
spool holder
https://www.thingiverse.com/thing:4490428 for this double part)

6. 
Print 4 of Bearing_608_slide_tolMax.stl with at least 101% scaled-up slice for easy mount
https://www.thingiverse.com/thing:4851975
4 double spool_holder_608z_rod.stl for mounting the bearings

7- 
Print two sets of this spool adaptor
https://www.thingiverse.com/thing:4845406

You can mount it with the original screws, if you don't want to unscrew the side spool holder screws, then you can use 2x 20mm M3 screws from your stash for mounting the front face part, but it won't be as cool imho.

You can consider supporting your Z gantry with this upgrade.
Gantry support for Ender 3 V3 Corexz
https://www.printables.com/model/882042-ender-3-v3-core-xz-gantry-stabilizer-support-rods  

Ok, I won't be writing more and confusing you with the details. Check out the photos and try to figure it out.

Some warnings for discouraging the beginners (!)

• Wait for the glue on the face part to cure before using it on the printer, especially if you are using super glue.
• No support, no brim. Use a 0.2mm layer height for everything.
• Print with a minimum of 3 walls and 50% infill using your strongest filament choice.
• It is highly suggested to use maximum infill for the screw related parts.
• Do not over-tighten the screws. Plastics and soft aluminium are not good with overdoing things.