Devices, methods and systems are described that enable achieving a working diameter during high-speed rotation that is greater than a resting diameter. The various embodiments comprise structural modifications to rotational drive shafts that result in a radial shift of the center of mass of an affected portion of the drive shaft away from the rotational axis of the drive shaft. As a result, high-speed rotation of the drive shaft induces orbital motion. Certain aspects include more dense plugs inserted into or integrated into one or more spaced apart locations in one or more wire turns or filars along the drive shaft. One or more filars may comprise a denser portion than other filars. A flexible strip of preferably semi-circular cross-sectional shape may be affixed to the interior of the drive shaft within the lumen to add mass and affect the location of the center of mass.
