Hello folks! :) 

Update December 28th 2025: Youtuber @Lukis 3D Studio made this awesome Video about the process of printing and assembling the Retracting Spool Holder! Check it out!

Special thanks to Luki, for providing us with this awesome video and allowing me to place it in this model description! 

Update November 9th 2025: FULL ASSEMBLY GUIDE NOW AVAILABLE! 

Update August 9th 2025:

Pro version, specifically designed for sensible materials and your top feed needs is now available!

[https://makerworld.com/models/1669393](https://makerworld.com/models/1669393)

I designed these handy spool holders for external materials. 

The filament can be retracted from the tool head without having to open the PTFE tubes and manually pulling it out. 

You can see how they operate here: 

To make the retraction mechanism work, you will need to use one of my dessicant tumbler designs. 

V2 (right picture) is my newer design: [https://makerworld.com/en/models/1347128](https://makerworld.com/en/models/1347128)

V1, the original design is part of this upload but can as well be found here: [https://makerworld.com/en/models/1233885](https://makerworld.com/en/models/1233885)

The Claw inside the spool holder engages the tumbler and translates your manual rotation to the *Bambu Lab Reusable Spool*.

I encourage you designers to come up with other versions for different filament brands.

EDIT May 9th 2025: SUNLU reusable spools are now integrated via adapter rings!!

[https://makerworld.com/models/1400108](https://makerworld.com/models/1400108)

How it works: 

The wheel in the front can be pushed in and out. 

The claw that attaches to the wheel on the inside of the box engages with the silica containers/tumblers so the spool can be turned. 

When the Wheel is pulled to the outside, the spool can turn freely.

These boxes hold the relative humidity under 20% for several months when the tumbler is filled with dry silica gel. (depending on the humidity in your area or course!) 

If you want to slice this on your own, be sure to set wall generator to “Arachne” for the big TPU seal (for the lid of the box).

As far as hardware goes, you will need the following parts: 

(list has been updated on 22nd of August 2025, i replaced the previously used M5 heat set insert by a printed thread!)
If you printed this model while i updated it, or if you prefer to use a M5 insert, the old source file for the rotary wheel will be kept online!)

• 4x “608” bearing (22mm outer ⌀, 8mm inner ⌀, 7m thickness) these are used in skateboards and rollerblades f.e. 
• 3x M3 Heat Set Insert (I use “Ruthex”)
• 1x M5x10-20mm Lenshead/Flat Head Screw 
• 3x M3x30mm Lenshead Screw
• 1x PTFE Tube Fitting (M6 Thread) 
• 1x Thermo/Hygrometer Round/Rectangular or Zigbee Sensor 

The Assembly Guide can be found as a PDF file attached to this post! 

have a nice day printing and consider leaving a like/boost if you like this design!

Cheers, MIM