Planetary reduction gear for belted z-axis driven by NEMA 17 stepper motor. It has a reduction ratio of 5:1 and 25 GT2 teeth. This results in 10 mm/rotation.
It may be mounted as a drop-in extension/replacement if your current drive has 25 teeth or close.
This is sufficient to prevent z-axis drop on power loss on experimental crossed cantilever 3d printer (see Casual CNC channel on YouTube) and might be suitable for other printers as well.
You will need following extra parts:
The parts in the video were printed on Creality K1C using TINMORRY ABS Pro filament with following key parameters:
It is essential, that parts are not sitting too tight. Prefer some backlash with lower friction over tight assembly. As a basic test, install the planetary reduction gear(s) on belted z-axis without the sun gear and see if axis still goes down. Expected: It should go down! Another positive sign is that a minimal drop is present on power off. This way backlash should not matter as the system is pre-loaded constantly in one direction.
There are 2 sizes of the case to choose from:
Video on assembly and mounting:
The author marked this model as their own original creation.