shown in fig7 which shows fly wheel 36 removed wherein one possible outer roller bearing assembly 58 is disclosed in this embodiment bearing assembly 58 comprises one or more circular outer bearing members or races 59 which comprise a circular circumference that mounts within an interior and or end portions of cylindrical fly wheel chamber 38 fly wheel 36 has an outermost diameter that may in one embodiment be about 80 90 percent of the circumference of cylindrical fly wheel chamber 38 the fly wheel chamber may typically have a diameter 40 75 or typically 55 65 of the tool diameter fly wheel 36 has a thickness of 10 to 30 of tool 10 the invention is not limited to this particular arrangement but is presently preferred furthermore in this embodiment fly wheel 36 is preferably offset within wheel chamber 38 the size mass of fly wheel 36 typically comprised of steel produces a gyroscopic effect during rotational operation of fly wheel 36 which may enhance propulsion produced by tool 10 as discussed herein the fly wheel may be mounted so that the center of mass is offset from the center of rotation by various means including an offset mounted shaft and or offset bearing.