Author: Crystal Bemis

Applying Position Tolerances to Countersunk Fixed Fastener Assembly Conditions

by Crystal Bemis on February 6, 2023.

When applying position tolerances to countersunk fixed fastener assembly conditions, our design must not only ensure assembly, but also that the fastener head sits flush or below the surface of the part. We are able to determine the values required to achieve this by using the fixed fastener equation.

Chamfer Dimensioning

by Crystal Bemis on November 10, 2022.

A chamfer is an edge feature commonly seen on part drawings, and consists of an angled cut on an internal or external edge of a part.

Fillets & Rounds

by Crystal Bemis on November 10, 2022.

Fillets and rounds are both radial edge features, with fillets applied to internal edges and rounds applied to external edges.

Break Edges Note

by Crystal Bemis on November 10, 2022.

“Break all sharp edges and remove all burrs,” is a common drawing note used to notify the manufacturer that the sharp edges and burrs produced by the manufacturing process must be removed from the part.

Knurling

by Crystal Bemis on September 19, 2022.

Knurling is a process used to create a pattern on the surface of a material by displacing or deforming the surface.

Common Thread Information: Diameters, Pitch, and Threads per Inch

by Crystal Bemis on August 22, 2022.

To understand the thread requirements on your drawing, you need to know common standard thread information. In this article, we will be discussing thread diameters, threads per inch and thread pitch.

Keyseats and Keyways

by Crystal Bemis on August 1, 2022.

A keyed joint is used to ensure orientation or restrict rotational movement between parts, as in the case of joining a shaft with a coupling. We discuss how a keyed joint is made and inspected in this article.

Applying GD&T to a Drawing Using Solidworks

by Crystal Bemis on July 5, 2022.

In this article, we outline the basic process for adding GD&T to your drawing using SolidWorks. The accompanying video goes into full detail, walking through the entire process for an example drawing.

Position Tolerance vs “True Position”

by Crystal Bemis on June 8, 2022.

Though many people refer to the GD&T Position symbol as "True Position," they are not the same thing. Read on to learn the difference between Position and True Position and how they work together to define the position of a feature.

Avoiding Tolerance Stacks with GD&T  

by Crystal Bemis on May 12, 2022.

Tolerance stacks can be a nightmare. However, when using GD&T rather than coordinate dimensioning, tolerance stack-ups within a part can be avoided.

The Problem with Reporting Basic Dimensions

by Crystal Bemis on April 28, 2022.

In Geometric Dimensioning and Tolerancing, Basic Dimensions are theoretically exact dimensions that define the ideal exact location and orientation of surfaces and features of size. A basic dimension is shown on a drawing as a...

Why Use GD&T?

by Crystal Bemis on April 27, 2022. (sticky)

We get a lot of questions from students asking why they would want to use Geometric Dimensioning and Tolerancing (GD&T) over coordinate dimensions. Some believe that using GD&T will result in tighter tolerances and increase...

The Datum Reference Frame

by Crystal Bemis on April 4, 2022.

What is a Datum Reference Frame? Datums are used in Geometric Dimensioning and Tolerancing drawings to create a reference system for inspecting a manufactured part. This reference system is called a Datum Reference Frame (DRF)....

Take our GD&T Skills Assessment Quiz!

by Crystal Bemis on January 28, 2022.

Having a good understanding of Geometric Dimensioning and Tolerancing is very important for anyone working in a mechanical field. GD&T is the language used in design, manufacturing, and quality inspection to communicate on engineering prints....

How to Use the Drill Tap Wall Chart

by Crystal Bemis on November 5, 2021.

The most common way to produce an internal thread is to drill a hole and then use a tap to produce the thread. This is usually referred to as a tapping drill for the size...

Part Setup and Datum Qualification Using a CMM

by Crystal Bemis on October 1, 2021.

GD&T Basics has partnered with Mitutoyo to demonstrate how to set up and inspect a part using a CMM. In this video, we examine a part designed as a training aid by Mitutoyo, inspecting it...

A Comparison of GD&T Standards: ISO GPS vs. ASME Y14.5

by Crystal Bemis on July 29, 2021.

What is the difference between the ISO and ASME GD&T standards? Read on to find the answers to these questions and more – and see our GD&T Standards Comparison Chart available to download for free below....

What is Geometric Dimensioning and Tolerancing (GD&T)?

by Crystal Bemis on June 9, 2021. (sticky)

What is GD&T? If you are involved in design or manufacturing, you may be familiar with the term, “GD&T,” or “Geometric Dimensioning and Tolerancing”. Geometric Dimensioning and Tolerancing is a set of rules and GD&T...