Abstract: A flexible cutting element composed of a plurality of chain links to which are attached tubular cutting units each of which is fabricated with a plurality of cutting teeth protruding upward and disposed at intervals extending radially around the periphery of the cutting unit. The direction of cutting of said cutting teeth are disposed alternately in opposite directions to enable said cutting element to cut a selected material when an oscillating motion is imparted. Various cutting unit designs are presented.

Abstract: A cutting apparatus designed to produce an oscillating force which is transmitted to a cutting element, said cutting element having a plurality of cutting teeth disposed at intervals in a complete circle around the periphery of the cutting element. The direction of cutting of the cutting teeth of said cutting element is alternated in opposite directions so that when to the cutting element is applied an oscillatory force, half of the cutting teeth will cut in one direction and the other half in the opposite direction. Thus the cutting apparatus disclosed herein is designed to work with any oscillating flexible cutting element of the type described above.