The updated and improved second edition of Direct Gear Design details a nonstandard gear design approach that makes it possible to significantly improve gear drive performance. Providing engineers with gear design solutions beyond standard limits, this book delivers engineers with practical and innovative solutions to optimize gearing technologies. The majority of modern gears are over-standardized, not allowing gear design engineers to see possible gear design solutions outside of standard limits. The book explores opportunities to improve and optimize gears beyond these limitations. The method of Direct Gear Design has been proven to maximise gear drive performance, increase transmission load capacity and efficiency, and reduce size and weight. Discussing the use of gears made from powder metal and plastic, the book surveys gear manufacture and makes use of extensive references to encourage further exploration of gear design innovation. Additionally, the book provides an overview of manufacturing technologies and traditional gear design, as well as covering topics such as asymmetric gears, tolerance selection and measurement methods of custom gears. Written accessibly, with a focus on practical examples, this fully updated edition will serve as a guidebook for all professionals exploring high-performance gearing system technologies.