Article Guidance:

Ⅰ. Dividing CNC Machining Processes:

Ⅱ. Principles for Arranging CNC Processing Sequence:

Ⅲ. Determining Workpiece Clamping Method:

Ⅳ. Setting Tool Points and Coordinate Systems:

Ⅴ. Choosing Cutting Paths:

Ⅵ. Monitoring and Adjusting During CNC Processing:

Ⅶ. Selecting Processing Tools and Cutting Parameters:

Ⅷ. Role of Processing Program Sheets:

Ⅸ. Preparations Before CNC Programming:

Ⅹ. Principles for Setting Safety Heights in Programming:

Ⅺ. Post-Processing of Tool Paths:

Ⅻ. DNC Communication:

CNC machining, also known as Computer Numerical Control machining, involves the use of computer-controlled tools for precision manufacturing. CNC machining offers numerous advantages, including stable processing quality, high accuracy, repeatability, the ability to create complex shapes, and efficient production. However, the human factor and operational experience significantly influence the final quality of CNC machining. Let's explore twelve valuable insights from an experienced CNC machinist with a decade of expertise:

Ⅰ. Dividing CNC Machining Processes:

When dividing CNC machining processes, consider the following methods:

1. Tool-Centric Approach: Group processes based on the tools used to minimize tool changes and reduce positioning errors.

2. Part-Centric Approach: Divide parts into sections based on structural characteristics like inner and outer shapes, curves, and planes.

3. Rough and Fine Machining Sequence: For parts prone to deformation, separate rough and fine machining to account for potential deformations after roughing.

Ⅱ. Principles for Arranging CNC Processing Sequence:

Arrange the processing sequence considering part structure, blank condition, and clamping needs. Ensure that the workpiece's rigidity isn't compromised.

Ⅲ. Determining Workpiece Clamping Method:

When selecting the clamping method, prioritize:

1. Consistency of benchmarks across design, technology, and programming.

2. Minimizing clamping steps for one-position machining.

3. Avoiding manual adjustments that occupy the machine.

4. Smooth clamping without interference with tool movement.

Ⅳ. Setting Tool Points and Coordinate Systems:

- Set the tool point on a finished reference position to avoid issues in subsequent processes.

- The workpiece coordinate system and programming coordinate system must align for consistent processing.

Ⅴ. Choosing Cutting Paths:

Select cutting paths with consideration for:

1. Meeting part accuracy requirements.

2. Simplifying numerical calculations and reducing programming complexity.

3. Minimizing idle tool time to enhance efficiency.

4. Reducing program segments.

5. Ensuring final contour processing occurs continuously in the last pass.

Ⅵ. Monitoring and Adjusting During CNC Processing:

Monitor the cutting process to maintain quality and prevent issues:

1. Monitor processing loads for adjusting cutting amounts.

2. Listen for changes in cutting sounds that signal issues.

3. Monitor finishing processes to ensure surface quality and dimension accuracy.

4. Check tool condition and address wear or damage promptly.

Ⅶ. Selecting Processing Tools and Cutting Parameters:

Choose tools based on material and application:

1. Carbide end mills for surface milling.

2. Carbide inserts for bosses, grooves, and box mouth surfaces.

3. Ball and round cutters for curved surfaces and variable bevel contours.

4. Consider factors like tool speed, feed rate, and cutting depth based on material and tool type.

Ⅷ. Role of Processing Program Sheets:

A processing program sheet describes the CNC program and helps operators understand key details, including:

- File names for drawings and programming.

- Workpiece names and clamping sketches.

- Program names.

- Tools used in each program.

- Maximum cutting depth.

- Processing properties (e.g., roughing or finishing).

- Theoretical processing time.

Ⅸ. Preparations Before CNC Programming:

Before programming, gather information on:

1. Workpiece clamping method.

2. Workpiece blank size.

3. Workpiece material.

4. Tool availability to avoid program modifications during processing.

Ⅹ. Principles for Setting Safety Heights in Programming:

Set safety heights higher than the highest island surface or position the programming zero point on the highest surface to prevent tool collisions.

Ⅺ. Post-Processing of Tool Paths:

Post-processing is necessary because different machine tools use various address codes and NC program formats. It ensures the programmed program is compatible with the specific machine tool.

Ⅻ. DNC Communication:

DNC (Direct Numerical Control) communication is a program transmission method used for large programs. It involves sending the program directly from a control computer to the machine tool, bypassing the need for program storage in the machine's memory. This approach avoids limitations imposed by memory size and ensures efficient program execution.