HappyHub - Improved Filament Loading for BoxTurtle (4-in-1 Hub)
Description
PDFThe 🥰 BoxTurtle's 4-in-1 hub can be a bit “temperamental” 😖 when loading filament in certain situations (especially on lane 4 ) with the filament getting caught and stuck in the bearing recess at the end of the filament path.
There is this remix which addresses the issue by stretching the hub in one direction (let's call this X) to extend the straight part of the filament path … and it works 👍.
But there is always room for improvement 😎
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- Stretching the hub not just in one dimension (X) but in two (X and Y) allows to place the new inlet positions exactly on the optimal filament path (instead of just shifting them forward)
- The increased spacing between the new inlet positions allows to redesign the junction: Junction of lane 2 and 3 is moved up which allows for a longer / better filament guiding for lane 1 and 4 before it hits the second junction point.
- Finally, the filament path is tweaked, slightly asymmetric and off-center just before the bearing which will push the filament away from the critical point at the end of the filament path while being inserted (at least in theory … in practice the stiffer the filament the less is the effect), without compromising the filament path during printing.
These changes should improve the reliability of the hub without adding any additional drag / resistance to the path. Happy Printing! 🤩
Tube Length
You will need to adjust the length of the PTFE tubes towards the extruders. Take the following values as a very rough estimate but adopt it step by step according to your specific setup:
Lane 2: 89 mm Lane 3: 90 mm Lane 4: 155 mm |
⚠ ECAS Press-In Trouble ⚠I successfully managed to damage the Hub when pressing in the four ECAS fittings on the input side: Either it separated or there were at least very visible stress marks in the ASA/ABS,. The changes in this remix should actually improve this issue as there is more material between the fittings compared to the original hub, but it still is a problem. So, if you are like me, use the Glue-In variant of the HappyHub which has a slightly wider opening for the four ECAS fitting on the input side (the one in the output is not critical and is unchanged). They still keep the fittings securely and centered, but apply a bit of super glue (to the outside of the ECAS fitting) to be on the save side. |
Changelog
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CAD
If you want to investigate a bit deeper or tweak it yourself: There is the Fusion file in the Files section, quite cleaned up, with this model, the original hub and also the remix I mentioned above all included, with timeline for all operations. So you can easily compare the three variants side by side to understand the differences and how the modifications were applied… and finally choose what you like.
Let me know if you have any suggestions!
… and maybe think about leaving a ❤ Like which makes me happy 🙂
CREDITS
BoxTurtle - Here on Github, what a fun project to build! 🥰
Hub Remix - Played around with this remix here on Printables and got some inspiration
Icon - … and the nice little drink for the turtle comes from loading.io
Tags
Model origin
The author remixed this model.
Differences of the remix compared to the original
Resized the hub and optimized the filament routing.