HEIDENHAIN ND 1200 - V2.16, Operating Instructions Manual, Page: 35 / 141

ND 1200 QUADRA-CHEK 35
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Measur
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Establish a datum
Establish a reference datum once the part is skewed. Two datums can
be created in the ND 1200. Typically, datum 1 is a zero reference and
used as an absolute or primary datum, while datum 2 is used as an
incremental or temporary datum.
Datums can be set to zero or can be preset to specified values.
Two methods can be used to establish a datum:
„
Zero or preset the X and Y axes on a point or on the center point of
a circle
„
Zero or preset the X and Y axes on a point or on a center point
constructed from parent features
While the datum can be created from a probed point or from the
center point of a probed circle, it is more commonly created from a
point that has been constructed from important parent features, such
as the skew alignment line and a second part edge line. An example
of a datum created from a constructed point is shown below.
Probe skew and part edge lines for point construction
Probe a Skew alignment line along the bottom of the part and probe a
line on the left side of the part. These lines will be used to construct a
datum point.
Perform skew part alignment to the X-axis on the bottom edge
U Press the SKEW key.
U
Probe 3 points along the bottom edge (points 1, 2
and 3).
U
Press the FINISH key to create the skew line.
Probe a line along the left edge
U Press the LINE key.
U
Probe 3 points along the left edge (points 4, 5 and 6).
U Press the FINISH key to create the second line.
The skew and left edge lines will now be shown in the feature list on
the left side of the DRO screen. The point construction using these
parent features is shown on the next page.
Constructions and the feature measurements necessary
for constructions are discussed in detail later in this
chapter. However, a brief example of constructions is
shown here to adequately cover the topic.
A skew is performed along the bottom and a line is
probed on the left side