steel ball track

Video
https://youtu.be/yOtMJRxr4qQ

Blender Animation
https://youtu.be/criKqJmFT0o

... an Archimedes screw lifts 8 mm steel balls to roll down a spiral track to feed an Archimedes screw ...

some hints
- the complete model (about 10 cm in height) was assembled and glued together with a soldering iron at 200 degrees (PLA)
- the motor is a 24.5 mm diameter, 12.5 mm thick, 3-6 V solar motor with 2 mm diameter and 10 mm length axle, for example RF-300CA or similar
- the gears must be aligned (and fixed) in right angle to their axles to avoid wobbling
- the archimedes screw bearings must be widened (with drill or file) to have some slip, use vaseline for lubrication
- there is also an electronic for collecting energy in a goldcap and driving the motor if enough energy is harvested

three versions of the track
- one piece (track_prop)
- split, low ground (track_split_gnd_low)
- split, props parallel to ground (track_split_gnd_prop)