Teaching GD&T Fundamentals in the Course Design of Machine Elements

Geometric Dimensioning and Tolerancing (GD&T) is an extremely important skill for mechanical engineering students who will mainly design mechanical devices and components. However, a GD&T course is typically not included in an undergraduate mechanical engineering curriculum. In our mechanical engineering curriculum, bits of basic concepts of GD&T are briefly mentioned or discussed in several different courses. It has been observed in the last several years that some students in their senior capstone project designs still didn't know how to properly define assembly dimension tolerances or component dimension tolerances. In the last two years, the authors used one and a half weeks out of a total of a fifteen-week semester to teach GD&T fundamentals in the course Design of Machine Elements. Homework assignments and quizzes were used to check or to reinforce their understanding of GD&T fundamentals. Also, students were requested to implement what they had learned about GD&T fundamentals in two design projects. This paper will present the approach of teaching GD&T fundamentals and present the results from a class survey. The results indicated that our teaching GD&T fundamentals did facilitate students to develop a better understanding of the GD&T fundamentals and to determine dimension tolerances of free dimensions and mating dimensions.