HEIDENHAIN ND 1400 - Manual (Page 72)

58 QC-300 Series User’s Guide
Probing cylinders
A minimum of six probed points are required to measure a cylinder.
The points must be probed beginning with two sets of three points; one
set of three at the top and another at the bottom of the cylinder. After
the initial six points, there is no practical limit to the additional number
of points that can be probed, and in general accuracy is increased by
probing more points. The first six points can be probed: three at the
top, then three at the bottom, or in the reverse order. Additional points
can be probed anywhere on the cylinder surface.
If the feature type is not interpreted correctly by Measure Magic, it can
be changed to a cylinder when more than six points are probed.
Measurement results are shown in the Feature list, View screen and DRO screen. The feature graphic in
the View screen shows the feature and the points used to define it. Errors are shown as whiskers connect-
ing the probed points to the feature. The maximum errors are shown in red and are used in the calculation
of form. The View screen shows location and angular displacement (shown below), form error, the number
of points used, reference frame and the projection plane (3D). When
only six points are probed, the form error is zero. When more than
six points are probed, the form error is the sum of the two greatest
opposing error magnitudes.
The angular displacements in the coordinate system orientation
shown here for a plane are designated as:
• Phi(Z) The angular displacement of the cylinder’s axis
from the reference frame’s Z-axis
• Theta(X) The angular displacement of the X-Y
projection of the cylinder’s axis from
the reference frame’s X-axis
Touch the feature type... to display the menu of alternative
feature types
Probed points are shown in the
View screen
Points can be probed starting at the
top or at the bottom