Difference between 3+2 positioning and Difference between 3+2 positioning and 5-axis simultaneous machining

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1. Introduction

In modern manufacturing, selecting the right machining method is crucial for improving production efficiency and product quality. Both 3+2 axis and 5-axis machining are common CNC machining techniques, each with unique features and suitable applications. This article provides a comprehensive comparison of these two methods to help you make informed decisions for your projects.

2. Basic Concepts

3+2 Axis Machining:

Also known as positional 5-axis machining, this method uses three linear axes (X, Y, Z) and two rotary axes (A, B). The workpiece is positioned at a specific angle before performing 3-axis machining operations.

5-Axis Machining:

All five axes (X, Y, Z, A, B) move simultaneously to achieve continuous 5-axis machining. This approach is ideal for complex surfaces and high-precision applications.

3. Structure and Motion Comparison

Feature 3+2 Axis Machining 5-Axis Machining
Motion Method Positioning first, then 3-axis cutting All five axes move simultaneously
Suitable Workpiece Workpieces with fixed angles Complex surfaces and multi-angle workpieces
Machining Flexibility Lower, limited by positioning angle High, capable of handling complex shapes
Machining Accuracy High, but limited by positioning precision Extremely high, suitable for high-precision requirements

4. Advantages and Limitations

3+2 Axis Machining Advantages:

  • Can use shorter, more rigid cutting tools.
  • Tools can be angled relative to the surface, allowing the spindle head to reach lower and closer to the workpiece.
  • Shorter tool travel distances and simpler program codes.

3+2 Axis Machining Limitations:

  • Typically sets a fixed angle for the spindle. Complex workpieces may require multiple tilted setups, increasing tool path overlaps and machining time.

5-Axis Machining Advantages:

  • Eliminates the need for specialized fixtures, reducing fixture costs and avoiding repeated setups, improving mold machining precision.
  • Fewer workholding devices required.
  • Reduces the need for special tools, lowering tooling costs.
  • Increases effective cutting length of the tool, reduces cutting forces, extends tool life, and lowers overall costs.

5-Axis Machining Limitations:

  • Slightly less rigid than 3+2 axis machining.
  • Not always suitable for short tools or large tool holders; vibration cannot always be avoided at certain tilt angles, potentially causing higher machining error than 3-axis setups.

5. Cost and Investment Considerations

5-axis machining equipment is generally more expensive and requires higher operator skill levels. However, for high-precision and complex-shaped parts, it can significantly improve efficiency and reduce labor costs. 3+2 axis machining equipment is more budget-friendly, but may require additional manual intervention when handling complex workpieces.

6. Suitable Scenarios and Selection Advice

Choosing 3+2 Axis Machining:

  • Suitable for simpler workpieces with fixed angles. It is an economical and practical choice.

Choosing 5-Axis Machining:

  • Recommended for complex surfaces, high-precision parts, or multi-angle workpieces, as it provides higher efficiency and accuracy.


At Rapid Model, we provide professional CNC machining services. If you’re unsure whether to choose 3+2 axis or 5-axis machining, simply share your requirements with our engineering team. We will analyze your project and help you select the most suitable machining method to maximize efficiency and market competitiveness.