About Datum Feature Creation
By default, the Model Tree displays each embedded datum as a feature subnode in the creation order, the last created item is displayed first. For a feature, the display of embedded datums and other subnodes on the Model Tree is in the order of sketch, annotation, embedded datums, and transformed or patterned features. The patterned, mirrored, or moved features are automatically grouped when you embed datum features in them. They are displayed in the Model Tree with labels that include the tool names, such as Patterned Features, Mirrored Features, or Moved Features. The embedded datum features are displayed as subnodes of the group header, above all other group members. The asynchronous datums with their respective feature are displayed as a feature subnode on the Model Tree. In the Model Tree, using drag and drop, you can convert a standalone datum to an embedded datum and vice versa
You can create all datum feature types, including points, axes, planes, coordinate systems, curves, graphs, and analyses, by using the commands in the Datum group on the Model tab.
During feature creation, model investigation, component assembly, and other operations, you are required to select one or more datum points, axes, planes, and/or coordinate systems, but in many cases the desired datum does not exist.
You can create datum points, axes, planes (including offset planes), curves, ribbons and coordinate systems at any time. You can create these features even during the creation of another feature, and then use them as references of that feature. At any point in feature creation, measurement, or analysis, if a datum feature is needed, you can create it.
This applies even for nested datum features, such as a condition where a point, axis, and plane must be created simply to get a reference for an offset make datum.
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Datum features, like other features, may have names that are identical to individual entity names. For example, a datum axis feature may contain an axis entity. In the former case, an axis is a type of feature, and in the latter case, it is a type of entity. Likewise, a datum point feature may contain many datum point entities.
For more information about and procedures for creating datum features, see the topics under Part Modeling in the Help Table of Contents.