Belt creep doesn't produce backlash but rather repeatibility errors.
Due to belt creep, there needs to be some indexing mecahnism to the
transmission medium so that the mechanism doesn't creep. You can do a
smooth belt if you repeatedly go back to a "start" calibration position more
often than the expected creep ould produce but if you're running something
like a mill or lathe, that really isn't practible, especially if the machine
isn't motor driven and able to slew to the reset position.

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Why do penguins walk so far to get to their nesting grounds?