New to This Edition • Expanded coverage and examples of features that have size and features that do not have size. • Updated information related to the datum reference frame concept. • Expanded datum defi nition. • Updated information about the symmetry line. • Additional information about the independency symbol. • Expanded content, examples, and calculations provided for MMC, LMC, RFS, MMB, LMB, and RMB. • Added bilateral position tolerance example. • Expanded examples and calculations showing how far off center two features can be when position tolerance is used to control coaxiality. • Added non-uniform profi le example. • Clarifi ed profi le tolerance and sharp corners. • Enhanced circular and total runout description and examples. • Expanded chapter tests and print reading problems. • New concepts added to the fi nal exam. • Updated actual industry drawing. • Added new drawing problems. GD&T Assessment and Testing Website David A. Madsen, coauthor of this book, has codeveloped a dynamic GD&T assessment and testing website to be used in conjunction with this text. The Geometric Dimensioning and Tolerancing Study Zone (www.draftingzone.com/ studyzone) is designed to help you gain an understanding of GD&T through an array of illustrated study resources. It contains challenging Study Questions that test knowledge of specific areas of GD&T. The comprehensive GD&T Practice Exams test your overall GD&T knowledge and ultimately, readiness for ASME’s GDTP Certification. This website is independent of Goodheart-Willcox Publisher. Acknowledgments We would like to give special thanks to the people who gave professional technical and industry support for this edition and past editions of Geometric Dimensioning and Tolerancing: • Patrick J. Brennan, Mechanical Engineering, Nuclear Fuel Handling, General Electric Canada, Inc. • Gary E. Garnier, Mechanical Design Engineer, Los Gatos, CA • David L. King, Technical Training Service, Lecturer, Trainer, and Consultant, Clinton, CT • James R. Larson, Ingersoll Milling Machine Company • Keith McDonald, Documentation Supervisor, FLIR Systems, Inc. • George Schafer, Manager Engineering Services, NACCO Material Handling Inc. Special thanks to Anthony J. Panozzo for his technical support and contribution of Appendix A3, Using GD&T Tools in SolidWorks. 6