How tight should the horn be (XH540-W270R)

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  1. What model of servo are you using?


I am assembling the horn to the dynamixel by following the video:

[Dynamixel] horn assemble (혼 체결) - YouTube

At 0:48, what does it say? I cannot read the sentence as both the letters and the background are in black. Does it say tighten to push the horn all the way in?

How tight should it be? Even I tightened the screw a lot, there was still an approximately 0.7-1mm gap between the horn and the dynamixel. Is this normal and acceptable? I got several units. Some are like that but others have a much smaller gap between the horn and the dynamixel. When I tightened as much as I could, it was very difficult to rotate the horn by hand even after I had attached a frame to the horn. I had to loosen the screw a bit to be able to turn it.

Will tightening too much damage the motor?

At 0:48 the following text is written.
“push it all the way in.”

It seems to be tighter than 0.7~1mm.
Please refer to the picture below.

If the washer position is not correct, the gap may widen and affect the operation.

Tightening the horn will not damage the motor, but it will damage the screws.