Fagor 8025 GP, Operating Manual

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126 8025/8030 CNC PROGRAMMING MANUAL
2 - Considerations on the sampling program.
The execution of the sampling program implies the following steps:
a) The probe will go to a specific point above the surface of the pattern.
b) Next, with the aid of function G75 the reading of the different coordinates (W), (V), X,
Y, Z.
After G75 the probe will lower as far as the programmed coordinate until it receives the
external signal of the probe. Once this has been received, the block will be considered
complete, the real position of the point of contact of the probe being accepted as the
theoretical position.
If the axes arrive at a programmed position before receiving the probe signal, the CNC will
indicate error 65.
c) With the aid of a block which contains the G76 function a block can be generated
which will be sent automatically, either to the CNC memory or to a computer via DNC.
The information after G76 can be:
- Coordinates of the (W), (V), X, Y, Z axes.
- G,F,S,T functions.
This entire process will be repeated for one of the points until the chosen sampling program
is complete.
3 - Final considerations.
Digitizing is always carried out within a defined volume. The planes which delimit this volume
are parallel to the machine axes. Thanks to the appropriate distribution of the planes parts of
the contour can be digitized.
It is possible to divide the surface of the pattern into several parts and define a different
sampling network for each area, all this by means of the combination of different sampling
sweeps which Fagor offers as an example.
The sequence of points must have a logical form for later machining, where the tool, with
the same shape as the probe ball, will travel over the line of points stored in the program. If it
is necessary to machine in several runs the program must be executed several times by applying
successive origin displacements or changes in the tool length compensation.
In a previous block, the control automatically reserves 100 blocks in which preparatory
functions can be defined which affect all the program: rounded edges, scale factor, axis
turn, etc.