Chris Lindenberg studied GD&T for decades while working in manufacturing. He has taught and written about GD&T for nearly ten years.
He writes this GD&T blog for Metalcraft because he says, "I’ve spent the better part of my career arguing the finer points of GD&T. These discussions are ongoing for any company that uses GD&T to manage their part geometry and control their parts’ allowable deviations from design models and standards."
This month, let’s review some definitions and rules. Let’s imagine that we’re going to make a simple part in our machine shop. The foreman returns to the quality lab or machine shop from a morning production meeting holding a customer’s drawing for a small shaft that will be sold to a customer in the aerospace […]Read More
I usually write blogs about how the symbols and rules that govern GD&T should be translated because it’s a system based on rules and definitions. What does parallelism mean? What rules govern datums used at maximum material boundaries? What exactly differentiates a regular feature of size from an irregular one? These questions are examples of […]Read More
GD&T is growing more common in our industry, which burdens us with forming a working knowledge of its convention. How we use and translate GD&T changes over the decades as new governing bodies take oversight and release new revisions. The one constant, however, is the great diversity of opinion on how to employ and translate […]Read More
Today’s manufacturing world is full of challenges and opportunities. Our shop technicians change hats hour by hour to download programs and accomplish their setups. Among other tasks, they pull material, load tools, and edit and rewrite code. They measure, adjust, and change offsets. They fill out their in-process inspection data and submit the first pieces, […]Read More
This month’s installment of our definition of terms will be about characteristic symbols. These symbols are what most people in the manufacturing world recognize as being what GD&T is all about and, from one perspective that’s true. Those Weird Hieroglyphic-Looking Things When the average worker in our manufacturing world first sees an example of GD&T, […]Read More
This month our definition of terms will look at regular and irregular features of size. Looking back we can see that a previous installment of our “definition of terms” looked at “features and features of size” which discussed features of size as they relate to parts and our larger scheme of geometric tolerancing. This discussion […]Read More
In our last blog post, we looked at the six common tolerance zones that appear in today’s engineering drawings. While these six make up the broad majority of tolerance zones in geometric dimensioning and tolerancing (GD&T), you may encounter another zone in a given tolerance scheme—the spherical tolerance zone. The American Society of Mechanical Engineers […]Read More
GD&T is a convention that gives the engineering world a tool that enables designed components to have both an unlimited variety of both geometric definition and tolerance. Consequently GD&T is about many things but it is ultimately about the disposition and appraisal of tolerance zones. This month our definition of terms will be about tolerance […]Read More