Chinese Harmonic 4th axis

[johnsattuk]

Harmonic drives have very low backlash, that looks like something loose inside where it is attached to the gear, bad key-way, loose bolts ??

[Rey8801]

Harmonic drives have very low backlash, that looks like something loose inside where it is attached to the gear, bad key-way, loose bolts ??

Not sure how it is connected inside but it is strange to me too. I might try to open it up in front. The runout is not measurable so will be really a pity if that can no be solved.

[Rey8801]

Harmonic drives have very low backlash, that looks like something loose inside where it is attached to the gear, bad key-way, loose bolts ??

Report here as well.
I made a video yesterday during the disassemble, just a random talk late at night, but it's useful to actually show how it is made. The backlash it's really from what I would call harmonic drive, but I am not an expert. What surprise me is that there are other users from this forum with the same drive and they claim almost ZERO backlash, so can be that I got a faulty one with maybe components out of tollerance. It seems the mesh inside the gearbox has a play before lock in place.

https://youtu.be/qgmcX7lL5zw