Computer Numerical Control (CNC) Programming

2.

Fundamentals of the CNC Machine Environment

2.1.

The Cartesian Coordinate System

2.1.1.

Three-Dimensional Space Representation

2.1.2.

X, Y, and Z Linear Axes

2.1.3.

Right-Hand Rule for Axis Orientation

2.1.4.

Rotational Axes

2.1.4.1.

A Axis (Rotation around X)

2.1.4.2.

B Axis (Rotation around Y)

2.1.4.3.

C Axis (Rotation around Z)

2.1.5.

Positive and Negative Directions

2.1.6.

Machine-Specific Axis Configurations

2.2.

Reference Points and Coordinate Systems

2.2.1.

Machine Zero (Machine Home Position)

2.2.1.1.

Homing Sequence

2.2.1.2.

Power-On Reference

2.2.1.3.

Machine Coordinate System

2.2.2.

Part Zero (Workpiece Zero)

2.2.2.1.

Work Coordinate System

2.2.2.2.

Setting the Work Offset

2.2.2.3.

Locating the Datum Point

2.2.2.4.

Use of Edge Finders and Probes

2.2.3.

Tool Reference Points

2.2.3.1.

Tool Length Reference

2.2.3.2.

Tool Tip Position

2.3.

Positioning Modes

2.3.1.

Absolute Positioning (G90)

2.3.1.1.

Reference to Fixed Origin

2.3.1.2.

Programming Applications

2.3.2.

Incremental Positioning (G91)

2.3.2.1.

Reference to Current Position

2.3.2.2.

Programming Applications

2.3.3.

Mixed Mode Programming

2.3.4.

Practical Applications and Examples

2.4.

Units of Measurement

2.4.1.

Imperial Units (Inches) - G20

2.4.2.

Metric Units (Millimeters) - G21

2.4.3.

Switching Between Units

2.4.4.

Implications for Programming and Tooling

2.4.5.

Resolution and Precision Considerations

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1. Introduction to CNC Machining

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3. The Language of CNC: Codes and Addresses