Partially Defined Drawings: Adapting to the World of CAD-Based, Geometry-Defined Working Drawings.

By Chris A. Lindenberger

In this blog, we’ll discuss the tendency for many engineers to produce partially defined drawings (PDDs) that contain elements of GD&T but leave off the applicable basic dimensions. Not only that, but they fail to note most of the X-Y dimensions that define the geometry.    CAD models don’t have tolerances and they don’t have […]

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Implications of the GD&T System for Communicating Tolerances

By Chris A. Lindenberger

The GD&T (Geometric Dimensioning & Tolerancing) protocol is rapidly becoming the standard for communicating engineering tolerances and allowable variation for product parts. It’s an elegant but not a simple system. Close to 50% of the GD&T drawings coming across my desk use the system incorrectly in whole or in part. This is not meant to […]

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