# Tag: datum features

## Radial Hole Pattern as a Datum Feature

by Crystal Bemis on May 27, 2024.

In this Question Line video, Jason responds to a question regarding radial hole patterns as datum features. He discusses how to set up the datum reference frame, how the datum reference frame controls degrees of freedom, and how to apply the Maximum Material Boundary.

## Inner or Outer Diameter as Datum Feature

by Crystal Bemis on October 9, 2023.

In this Question Line Video, Jason discusses datum preferences for hollow cylindrical parts, where both the ID and OD of the part are mating features.

## Datums, Datum Features, and Datum Simulators

by Crystal Bemis on August 11, 2023.

In this Question Line Video, Jason uses the example of a cylindrical datum feature to show how non-planar datums can be simulated and how they are able to constrain degrees of freedom.

## Locating Datum Features

by Crystal Bemis on June 5, 2023.

Why doesn't a feature of size that is indicated as a datum feature need to be located? In this article and corresponding question line video, we look at two drawing examples to illustrate why datum features are not located.

## Sheet Metal Holes as Datum Features

by Crystal Bemis on May 16, 2023.

If I specify a hole in a practically thin feature, such as a piece of sheet metal, is this still considered a cylindrical datum? Is this a poor choice of datum? In this article, we look at an example to help us answer these questions.

## Common GD&T Student Questions: Perpendicular Datums from Imperfect Features

by Crystal Bemis on April 6, 2023.

How can datums be perfectly perpendicular to each other when the features themselves are likely imperfect? The feature axis and the datum axis derived from the feature are found in two different ways, using the Unrelated Actual Mating Envelope and the Related Actual Mating Envelope.

## Common GD&T Student Questions: A Pattern of Holes as a Datum Feature

by Crystal Bemis on March 28, 2023.

We often see a pattern of holes indicated as a datum feature in a GD&T drawing. How do we simulate this to create our datum reference frame?

## Common GD&T Student Questions: A Single Point as a Secondary Datum

by Crystal Bemis on March 17, 2023.

Can a single point (without clocking) be used as a secondary datum in a feature control frame? To answer this question, we first need to determine what datum feature is being represented by this single point. Read on to discover the answer to this commonly asked question from our GD&T students.