3 Axis vs. 4 Axis CNC: Choosing the Right Router

济南名仕机械设备有限公司Jinan Mingshi Machinery Equipment Co. @ Mar 28, 2025

Many CNC buyers struggle to choose between a 3-axis and a 4-axis CNC router. To help you make an informed decision, this guide will cover the key differences between the two, including:

What is a 3-axis vs. 4-axis CNC router?
Differences in machine configuration
Capabilities and functions
Applications in different industries
How to choose the right CNC router for your needs

1. What is a 3-Axis and 4-Axis CNC Router?

3-Axis CNC Router

A 3-axis CNC router is the most basic type of CNC machine, capable of cutting, engraving, drilling, and milling by moving along the X, Y, and Z axes. It is widely used in woodworking, advertising, and furniture manufacturing for flat panel processing and simple engraving tasks.

While a 3-axis CNC router is a great starting point, it can be upgraded to multi-process CNC, dual-station CNC, or multi-head CNC for increased efficiency.

4-Axis CNC Router

A 4-axis CNC router has an additional rotary axis (A-axis), which allows for more complex processing. It is divided into two types:

Swinging Spindle 4-Axis CNC Router – The spindle can rotate 180° left and right, making it ideal for 3D surface machining and multi-sided engraving.
Rotary Axis CNC Router – A rotary device is added to the 3-axis CNC router, enabling cylindrical object processing such as table legs, stair railings, and Roman columns.

4-axis CNC routers are ideal for advanced 3D carving, artistic engraving, and complex mold making, making them popular in industries like woodworking, stone engraving, and metal processing.

2. Key Differences in Machine Configuration

Feature	3-Axis CNC Router	4-Axis CNC Router
Machine Structure	Standard machine bed	Reinforced bed for greater stability at high speeds
Motor Type	Stepper or servo motor	Requires a 850W+ servo motor with a reducer
Guide Rails	20mm or 25mm linear rails	Uses 25mm+ rails for higher precision and load capacity
Control System	Mach3, DSP, NK105	Uses Syntec, Baoyuan, Siemens for high-precision control
Cooling System	Manual spray cooling	Automatic oil mist/water spray cooling for metal and stone processing

3. What Can a 3-Axis vs. 4-Axis CNC Router Do?

3-Axis CNC Router Capabilities

✅ Flat surface engraving & cutting
✅ Simple cutouts & text engraving
✅ Ideal for materials like wood, acrylic, PVC, and plastic

Common applications:

Woodworking: Cabinet doors, solid wood doors, screen panels, wave boards
Advertising: Acrylic engraving, PVC cutting, sign-making
Basic mold making

🔹 Limitations: Cannot perform complex 3D carving or cylindrical processing.

4-Axis CNC Router Capabilities

✅ 3D carving & curved surface engraving
✅ Multi-sided machining
✅ Rotary engraving for cylindrical objects

Common applications:

Wood carving: Buddha statues, Roman columns, chair legs
Stone engraving: Monument sculptures, decorative stonework
Metal processing: Aluminum, copper, and other non-ferrous materials
Mold making: Automotive and aerospace components

🔹 Best for industries requiring high-precision and 3D capabilities.

4. Which Industries Use 3-Axis and 4-Axis CNC Routers?

Industry	Recommended CNC Router
Woodworking	3-axis (for flat work), 4-axis (for 3D carving)
Advertising	3-axis CNC
Mold Making	4-axis CNC (for complex 3D molds)
Stone Engraving	4-axis CNC (for detailed sculptures)
Metal Processing	4-axis CNC (for precision engraving)

5. How to Choose the Right CNC Router?

Choose a 3-Axis CNC Router If:

✅ You only need flat surface engraving and basic cutting
✅ Your primary materials are wood, acrylic, PVC, or plastic
✅ You are on a budget and looking for an entry-level CNC machine

Choose a 4-Axis CNC Router If:

✅ You need 3D engraving, rotary engraving, or complex carving
✅ You process cylindrical objects like columns, table legs, and railings
✅ Your materials include hardwood, stone, or metal
✅ You want to invest in a more advanced and versatile CNC machine

6. What to Consider When Buying a 4-Axis CNC Router?

🔹 Rotary Axis Placement:

If placed on the worktable, it does not affect processing size and can be removed when not in use.
If placed on the side, check the effective processing size of the machine.
For large-diameter rotary workpieces (>200mm), an independent rotary axis is recommended to avoid reducing the processing range.

🔹 Swinging Spindle CNC Considerations:

Swinging the spindle can reduce the effective machining width.
High precision is needed to maintain accuracy in multi-axis machining.

🔹 Choose a Reliable CNC Manufacturer:

Make sure the manufacturer provides strong technical support and high-quality assembly.
Mingshi Machinery offers customized CNC solutions with advanced technology and top-tier support.