computer numerical control programming basics - Industrial Press

Fig. 18 The first step in producing a CNC program is to take the information from the print and
produce a program manuscript. (Deckel Maho, Inc.)
Dimensioning Guidelines
The system of rectangular coordinates is very important to the
successful operation of CNC machines. Certain guidelines should
be observed when dimensioning parts for CNC machining. The
following guidelines will insure that the dimensioning language
means exactly the same thing to the design engineer, the technician,
the programmer, and the machine operator.
1. Define part surfaces from three perpendicular reference
planes.
2. Establish reference planes along part surfaces which are
parallel to the machine axes.
3. Dimension from a specific point on the part surface.
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