Quote Originally Posted by iD2 View Post
That was dampers , it come with stepper motor.
Looks cool. Practical if you need to manually move an axis. Just don't rotate too fast because the motors work as generators as well, and will feed back currents the wrong way. Depending on your stepper driver, it may cause harm if you rotate the dial too fast.

Do you really feel the need/use of dampers? Have you tried with/without? OK, it came with the machine, so no reason not to have them, but I am curious if they are actually doing anything useful.