A datum
is a plane, a straight line, or a point
used
as a reference to measure and locate geometric entities and geometric
tolerances.
Use the AM_DatumIdentifier command
to create datum identifier symbols.
Datum
identifier symbols identify datum features for feature control frame symbols. For
example, you can use a datum identifier symbol to mark the center of a
hole.
When you create a datum
identifier
symbol in a drawing,
the
software generates a
label
that contains the datum
identifier
enclosed in a rectangle. The datum
identifier
appears in all feature control frames that use the datum as a reference. A leader line
connects the label to the datum on the drawing. The leader line may include a filled or
empty triangle. The position of the triangle indicates the corresponding
datum.
Elements of
Datum
Identifier
Symbols
| 1 |
Square frame |
| 2 |
Datum
identifier
of
two
capital
letters
maximum |
| 3 |
Leader arrow |
| 4 |
Triangle symbol |
You can attach datum
identifier
symbols on:
- A
surface or on one extension line of
a
surface
- Visible
lines
such
as
extension lines, dimensions, or axes
- A
hole, leader pointing to
a
hole, or feature control frame
Examples of Datum Identifier Symbol:
On a surface and on an
extension line
On a point
