Light 18-volt batteries have become the standard for cordless power tools, but they often underperform when faced with difficult tasks such as boring large holes into wood or metal. To produce more strength without resorting to a heavier, higher-voltage battery, engineers at Milwaukee redesigned the motor of the new M18 Fuel drill. The result is a tool that generates about 25 percent more torque than the average 18-volt drill and can create big holes faster than any of them.
Most power tools use motors that employ conductive brushes and pieces of copper to generate an alternating magnetic field that drives the rotor. To increase the M18’s torque, engineers replaced brushes with a small electronic circuit board, leaving more room in the motor for rotor-driving magnets. The 4.3-pound tool yields 725 inch-pounds of torque, 30 percent more than its predecessor. All that extra strength doesn’t kill the drill’s battery life, though. The new motor is also more efficient, allowing the drill to run at least 50 percent longer per charge compared with the previous model