Time to read: 7 min
5-axis CNC machining is an advanced form of subtractive manufacturing that allows manufacturers to create highly complex, high-precision parts in a single setup. Like other CNC processes, it works by removing excess material from a workpiece using cutting tools. Parts can be shaped from different materials, such as metals, plastics, and composites. Product teams can choose from different configurations of 5-axis machining, such as 3+2-axis and simultaneous 5-axis.
Read on to take a closer look at 5-axis machining, its practical forms, how multi-axis machining works, and benefits and applications of 5-axis machining.
What Is 5‑Axis CNC Machining?
5-axis CNC machining is an advanced manufacturing process that moves a cutting tool and/or workpiece along five different directions at once. These include three linear movements (left-right, front-back, up-down) plus two rotational movements that allow the tool or part to tilt and turn. This lets the machine cut complex angles and shapes in a single setup, unlike more traditional milling and turning processes.
Standard (3-axis) milling typically removes material in three linear directions, while turning removes material by spinning the part around an axis. Together, these manual processes can achieve increased degrees of freedom but usually require multiple machining setups to accomplish this.
In contrast, 5-axis CNC machining offers linear and rotational motion in the same setup. This enables the creation of intricate features more quickly and accurately, with reduced material waste. Many 5-axis machines also feature automated tool changers controlled by software.
5-axis machining is valued in many industries, from aerospace and automotive to medical, consumer products, and climate tech. It’s used to produce complex, high-tolerance parts like turbine blades, engine components, orthopedic implants, electronic casings, and precision shafts, among many other specialized components.
What Is the Difference Between 3‑Axis, 3+2-Axis, and Simultaneous 5‑Axis Machining?
These days, there are many options when it comes to CNC machining, ranging from traditional 3-axis machining to multi-axis machining options with 4, 5, 7, 9, and even 12 axes of motion.
Let’s take a look at how 3-axis, 3+2-axis, and simultaneous (or true) 5-axis machining work and what makes each unique.
3‑Axis Machining
In 3-axis machining, the toolpath is limited to linear movements along the three primary axes: X (left to right), Y (front to back), and Z (up and down). More specifically, the tool can move horizontally or vertically to adjust the cutting depth. The tool’s orientation remains fixed, so all cutting is performed in a single direction at a time. This method works well for parts with relatively simple shapes but may require multiple setups for more complex geometries.
Each repositioning adds time to the process and increases the risk of small alignment errors. It is ideal for creating simpler parts with less dimensional complexity. Because 3-axis machines are generally more affordable than multi-axis alternatives, they are a popular choice for startups and small to medium-sized businesses, especially for shorter production runs where keeping costs low is important.
3+2-Axis Machining
3+2-axis machining is also known as “positional 5-axis machining.” This approach adds two rotational axes to the standard three linear axes, allowing the cutting tool or workpiece to be tilted into position so that multiple sides of a part can be machined without manual repositioning. Once positioned, the cutting is carried out using the three linear axes only.
The main benefit of upgrading to a 3+2 setup is the ability to machine a workpiece from multiple sides in a single setup. This significantly reduces the need to manually reposition the part, cutting down cycle time and lowering production costs. Another advantage is that 3+2 machining can use shorter, more rigid cutting tools compared to standard 3-axis machining. This improves tool stability and results in better dimensional accuracy and surface finish.
Simultaneous 5‑Axis Machining
With simultaneous 5-axis machining, the machine moves the cutting tools dynamically through five axes of motion: three linear axes and two rotational axes. This means that the cutting tool can move and rotate continually through cuts. Movements in these five axes work together to shape the desired component in a single setup. It is especially valuable for parts with curved surfaces, undercuts, or complex contours, such as turbine blades or orthopedic implants.
Benefits of 5‑Axis Machining
5-axis machining offers several benefits compared to traditional 3-axis machining:
- Accuracy: Because the cutting tool can approach the workpiece from more angles without repositioning, the risk of misalignment and human error is greatly reduced. This means that every cut is precise and consistent.
- Complexity: Parts such as turbines and combustion chambers can be machined as single pieces instead of being assembled from multiple components. This not only reduces the number of assembly steps but also cuts down on potential failure points and overall cost.
- Speed: With 5-axis machining, multiple faces of a part can be worked on in a single setup. This decreases setup time and reduces the need for human intervention, ultimately leading to faster production and shorter delivery times.
Potential Drawbacks of 5-Axis CNC Machining
While 5-axis machining offers flexibility and precision, it’s not always the right fit for every project. Some considerations include:
- Higher Costs: 5-axis machines are more expensive to purchase, program, and operate compared to 3-axis or 4-axis systems. This often translates into higher per-part machining costs, especially for simple geometries that don’t require multi-axis capability.
- Programming Complexity: More axes mean more complex toolpaths. CAM programming requires specialized expertise and longer setup times, which can increase lead times if the geometry doesn’t truly demand 5-axis capability.
- Machine Availability: Not every shop has 5-axis CNC equipment, and lead times may be longer depending on machine capacity and demand.
- Overengineering Risk: In some cases, using 5-axis machining for a relatively simple part can drive up costs without adding value. Matching the right machine to the job is critical.
How to Choose the Right Number of Axes
When deciding whether your part needs 5-axis CNC machining, consider the following factors:
- Part Geometry: Parts with angled features, undercuts, or complex organic shapes are best suited for 5-axis machining. If features are accessible from only one or two orientations, 3-axis machining may suffice.
- Tolerances and Surface Finish: Tighter tolerances and smoother surfaces often benefit from 5-axis machining because the tool can maintain optimal cutting angles with fewer setups.
- Production Volume: For high-volume runs of simpler parts, 3-axis machining is often more economical. For low-to-medium volumes of complex parts, 5-axis machining reduces setup time and increases repeatability.
- Lead Time Requirements: 5-axis machining can reduce the need for multiple setups, speeding production of complex geometries. However, if your part is simple, setup on a 3-axis machine may actually be faster.
- Budget: If cost control is a top priority, consider whether the complexity of your part truly warrants 5-axis machining. Otherwise, a lower-axis approach may provide better value.
Rule of Thumb: If your part requires machining on multiple sides with critical tolerances, or if tool access is restricted in standard orientations, a 5-axis solution is likely the best choice.
Design Guidelines for 5‑Axis Parts
While 5-axis CNC machining follows the same basic rules as traditional CNC machining, the ability to tilt and rotate the tool or workpiece introduces new possibilities and new considerations.
Although it offers greater flexibility and can produce more complex geometries than 3-axis machining, unnecessary complexity should be avoided as it can lead to longer cycle times, higher tooling wear, and increased costs. Design parts with only the details necessary for function, and ensure any added complexity has a clear purpose.
Fillets reduce sharp internal corners that are difficult for cutters to reach, while draft angles improve tool engagement and surface finish. Adding overflow stock (a small amount of extra material) is useful for secondary finishing or polishing to ensure that the final dimensions are met after all machining passes.
Fixture placement and datum strategy are also critical. The initial fixture design should allow full access to all machining areas without interference. Datums should be positioned so all critical features can be referenced in one setup.
Precision and Tolerance
In most ways, precision and material considerations for 5-axis CNC machining align with general CNC guidelines, but with tighter control thanks to its advanced capabilities. While general CNC milling holds around ±0.05 mm (±0.002 in), 5-axis often achieves ±0.01–0.02 mm (±0.0004–0.0008 in) range and, under favorable conditions, can reach ±0.005 mm (±0.0002 in), for critical aerospace or medical parts.
Tolerance accuracy depends on the material, geometry, and other factors. See our full chart for CNC tolerances. You can also download our design guidelines for CNC machining.
Costs & Service Considerations for 5-Axis CNC
Quoted prices for 5-axis machining work often differ from 3-axis work due to additional programming requirements, more complex toolpaths, and longer machine setup times. Hourly rates are typically higher for 5-axis machining, especially for parts with complex toolpaths. Pricing is usually tiered based on factors such as minimum volumes and part complexity. Lead times can also vary. Simple parts may be turned around in days, while highly complex parts, like aerospace or medical components, might take a few weeks to complete.
Choosing a 5‑Axis Machining Service Provider
When selecting a CNC machining service, look for proven adherence to manufacturing standards such as ISO 9001 or AS9100 certification, strong DFM feedback capabilities, and easy access to a range of material options. A good supplier will also offer clear, transparent quoting with an understanding of how to optimize designs for 5-axis machining efficiency.
Fictiv’s supplier network leverages a multi-source supplier model, giving customers access to vetted manufacturing partners with diverse capabilities, specialized materials knowledge, and flexible capacity to meet tight deadlines. This allows our customers to move from a CAD model to a finished part quickly.
Unlock Complex Designs With 5-Axis CNC Machining
5-axis CNC machining is one of the best options available to designers and engineers who are working on complex parts that need to be produced fast, with tight tolerances. Its ability to machine intricate geometries in a single setup not only reduces errors and cycle times but also unlocks design possibilities that traditional 3-axis machining cannot match. For teams evaluating new parts or considering their manufacturing process options, exploring 5-axis machining early in the product development design phase can save time and money.
Need precision parts with complex features? Fictiv offers full simultaneous 5‑axis CNC machining with expert DFM feedback and fast quoting.
Discover how 5-axis machining can unlock new possibilities for your projects and save you time and money along the way. Get started with a free instant quote today.
