Today’s manufacturing industry relies on the use of GD&T definitions, and the ability to verify parts directly to them for first article and production inspection and reporting. Only then do orders ship and the manufacturer gets paid. Price and scheduling are negotiable, quality is not!
Geometric dimensioning and tolerancing (GD&T) is a system of symbols, definitions, and rules used by engineers to communicate design intent through engineering drawings and computer-generated three-dimensional models. The system explicitly describes nominal geometry and its allowable deviation. GD&T is recognized as a universal design language and has been rigorously studied and used by manufacturers around the world. GD&T is not only an essential tool to communicate design intent, it also simplifies and reduces the amount of overall design requirements while maintaining adequate definitions to verify that finished parts have the desired form, fit, function and interchangeability.