Edit 2:
The V2 version was tested with great success. This is no longer a WIP.

Edit:
Added a V2 version of the coupling with a better fit to the blender and other accessories (more robust?).

I still haven't tested it under normal working conditions (stress).

Original:
My motor coupling broke and there're not many spare parts in my country, so I TinkerCAD this. It's still a WIP. It fits and turns well, but I have done no real blending testing yet.

I have no responsibility on how you use this or any injuries derived from its use.

https://youtu.be/lREpc8UM1S4

Creality

Ender 3

No

Yes

0.160

50%

5 walls for strength