Hi David,
The middle datum image that has the hash marks (-A-), in the Datum Properties Box, is what is used to actually set an axis as adatum. For instance, Right-Click Axis Y in the model tree, Properties, then click the middle -A- and choose how to apply the datum. If you click the right, suction cup, image, you will be making theaxis a Datum Tag Annotation, instead. If you hover your mouse over the images, there will be a short description of what they do.
Here is some information from the Help File aboutDatum Tag Annotations.
About Set Datum Tag Annotations in Annotation Elements
You can create a set datum tag as an annotation placed on an annotation plane,
and referencing a datum feature or a surface associated with a datum feature.
The set datum tag Annotation Elements appear with the datum name in a box that
is attached to a solid triangle. Set datum tag Annotation Elements are displayed
in the Model Tree in the Annotation Feature as AE_SET_DATUM_TAG_<datum_name>
while the set datum tag annotations are displayed as Datum_Tag_<datum_name>.
Note the following points about set datum tag Annotation Elements.
• When creating a set datum tag Annotation Element, you can reference an
existing datum plane or datum axis. Alternatively, you can reference a planar
surface, cylindrical surface, circular edge or curve. When you reference a
planar surface, cylindrical surface, circular edge or curve, a datum feature
is created. For example, if you reference a planar surface then a datum plane
is created and if you reference a cylindrical surface, curve, or edge, then a
datum axis is created. This datum feature that is created is used as a reference
for a set datum tag Annotation Element. After the set datum tag Annotation Element
is created, the relationship between the set datum tag Annotation Element and the
reference datum feature is a parent-child relationship.
• You can place set datum tag Annotation Elements on a datum, or attach to a
dimension or GTOL and on geometry. You can place a set datum tag on geometry, such as,
on a coincident surface, edge or curve, coplanar surfaces with set datum planes, and
cylindrical surfaces with a set datum axis.
• You can include the set datum tag annotation elements in a User Defined Feature
(UDF), only if the UDF contains the reference datum feature, and also the geometry
references, if any, of the set datum tag Annotation Elements.
• Similarly, you can propagate set datum tag Annotation Elements to a Data Sharing
Feature, only if the Data Sharing Feature contains the references of the set datum
tag annotation element. You cannot propagate set datum tag annotation elements in the
same model.
Hope this helps...Brian
