Well that was a disappointment.? I used 1.5mm and 40% infill.? After 3 hours it came off the build plate and the gears were not locked.? But it really meshes too loosely.?
?
In the photo you can see a pipe cleaner I'm using as a simulated tube which shifts the assembly in the area where there is no tube and then one of the bottom gears disengages.?
?
I think the only way this would work is the same way a planetary gear system does with a carrier that keeps the gear spacing correct.? Push hard enough in the no tube area and the bottom gear falls out.? You can see in the photo the bottom one barely engages.