Abstract: A machine for improved excavation of underwater rock that eliminates failures due to over-stressed cutting teeth by positioning each hardened tooth for optimized Kinetic Energy. It has a plurality of blades, each with a hub and a plurality of spokes connecting the hub to a rim. Teeth are mounted on the leading edge of each blade approximately equidistant from the cutter axis of rotation, allowing each tooth to have the proper combination of velocity and cutting force required to shatter massive, hard rock. As a result, all teeth have approximately the same peripheral velocity; have adequate Kinetic Energy to shatter rock upon impact, and are subject to approximately the same maximum stress during rock excavation.