Why 5-Axis Machining for Defense Components?

The defense industry relies on subtractive manufacturing techniques like CNC machining for much of the equipment used by various branches of the military and related defense contractors. In particular, 5-axis CNC machines are used instead of less advanced 2-axis, 3-axis, and 4-axis CNC equipment to make parts with more complex geometries, tighter tolerances, and better finishes. 5-axis machines provide components with tighter tolerances and better surface finishes with the need for fewer setups. Additionally, their ability to produce complex components accurately means 5-axis machining of defense components can be done better. This helps machine shops better comply with standards like the International Traffic in Arms Regulations (ITAR) and AS9100 certifications, both of which offer guidelines for military-grade products for the US military.  

Using 5-Axis CNC Machines for Military Applications

A truly 5-axis CNC machine can work on five axes simultaneously, while a 3-axis machine can only work three axes simultaneously, with two fixed axes that can only be used for positioning. Similarly, 4-axis machines can work simultaneously on four axes, with one static axis used for positioning a workpiece.  

The less time spent repositioning a workpiece also decreases human errors, along with lower lead times and production costs. Even projects that require only three or four axes can be done more quickly and efficiently with a 5-axis CNC machine since cutting tools remain close to the cutting surface to allow greater material removal with every pass.

Advantages a 5-axis CNC machine working on five axes include:

• Accelerating machining times due to constant control of the pathways tools follow.  
• Allowing a workpiece to be held with a single chuck significantly decreases the need for multiple setups.
• Creating better clearance for tools to lower restrictions on shaping a workpiece by enabling tilting of the chucking device.
• Enabling the production of highly complicated geometries.
• Helping maintain optimal positions for cutting tools to lengthen their life, while also lowering cycle times.
• This improves surface finishes, as the cutting tool has closer access to the workpiece, reducing vibrations that can affect the finish.
• Minimizing greatly the chance of collision between machine, tools, and workpieces.
• Optimizing efficiency and decreasing lead times through the need for fewer operator interventions.
• Permitting undercutting without the need to reposition the machine, as cutting tools can approach a workpiece from every direction.
• Determining the cumulative effects of various tolerances in a workpiece, also known as “stacking up” tolerances, can reduce scrap while also improving quality.

The ability to machine on five axes simultaneously has created incalculable potential for the defense industry. 5-axis CNC machines help machine shops more efficiently produce military-grade products. Yet, though many machine shops advertise their capabilities for machines that work on five axes, 5-axis CNC machines’ capabilities cannot be achieved by machines that only operate on three or four axes. 

Why Use a 5-Axis CNC Machine

The distinct advantages of 5-axis CNC machines over less sophisticated machining equipment include greater accuracy and complexity, fewer setups, capabilities for machining on multiple axes, lengthening the life of tooling, and improved surface finishes.

Greater Accuracy & Complexity

Like their civilian counterparts, the jets, helicopters, and other aircraft used by the military require incredibly complex components to ensure they perform as they should. Through their ability to better position and move workpieces, 5-axis CNC machines enable more accurate cutting. This leads to superior precision, facilitating more complex geometries. Also, with less manual interaction between a machinist and the CNC equipment, there are fewer opportunities for human error.  

CNC machines that work on only three or four axes would require multiple setups and other human intervention to create these types of parts. A 5-axis CNC machine can complete these features in a single pass, consistently improving accuracy. The continuous maneuvering on five axes allows precise machining of arcs, angles, holes, sculpted surfaces, and other specialty structures without requiring multiple setups or additional equipment.

Reduced Setups

With a 5-axis CNC machine, tooling can reach almost all the surface area of a workpiece, except for the clamped area. This means less downtime to reposition items during machining, often limiting this to a single setup. As each new setup requires a recalibration and reset of the CNC machine, it adds to the cost and time it takes to produce components. This improves a machine shop’s overall efficiency, while also reducing the risk of misaligned workpieces or other errors during setup.

Multi-Axis Machining

While a 5-axis CNC machine can do everything a 3-axis or 4-axis machine can, neither offers simultaneous machining along five axes. Two axes with 3+2 movements or one axis with 4+1 movements remain immobile in these approaches, requiring more workpiece repositioning. The 5-axis CNC machines allow cutting tools to contact any part of the workpiece from nearly every angle without repositioning.

Longer Tool Life

Using a 5-axis CNC machine extends the life of tools in numerous ways, mostly due to simultaneous machining on multiple axes.

5-axis CNC machines optimize tool life by: 

• Augmenting the removal of chips from cutting, which in turn reduces the buildup of heat and resulting wear.
• Orienting and maintaining an angle to the workpiece that reduces tool wear.
• Providing continuous movement to provide consistent wear across the tool’s surface, thus retaining the cutting edges of tools for longer.
• Reducing the need for manual repositioning, which can lead to misalignments caused by human error.   
• Requiring fewer restarts avoids wear from the reengagement of the tool with the surface of a workpiece.
• Speeding up cycle times through automatically repositioning the tool or cutting table to optimize the position of the workpiece.
• Stabilizing the cutting process with greater precision reduces imbalances, decreasing vibrations that lead to wear.

By optimizing tool use, 5-axis machines prevent tools from becoming dull and ineffectual prematurely. This, in turn, lowers operational costs while improving quality and productivity.

Better Surface Finishes

As a workpiece rotates on the A and B axes, it‘s brought closer to the cutting tool. This permits machines to use shorter tools, which are less vulnerable to the vibrations resulting from higher cutting speeds. These vibrations directly affect the surface finish, with the improved ability to position workpieces decreasing or even eliminating the need for secondary finishing processes.

Military Applications for 5-Axis CNC Machines 

Though not all 5-axis CNC machines are used for military applications, many of the products produced with this technology involve contracts or projects for the US government. A 5-axis CNC machine can do everything CNC equipment operating on fewer axes can do, but more quickly and with greater accuracy. Further, their ability to form complexly shaped components quickly makes them ideal for an assortment of applications.

5-axis CNC machines are used in the making of military components that include: 

• Bearings and bushings
• Bolts, bushings, clamshells, connectors nuts, end plugs, pins, plates, retainer rings, rivets, screws, shafts, tubes, and other basic components within military equipment
• Buttons, dials and other terminal components
• CAMS (control and monitoring systems) components
• Couplers, heatsinks, and other aerospace components
• Flanges for aircraft ducting
• Frames for aircraft seats
• Gun, rifle, and other weapon barrels
• Hoist components for munitions
• Military vehicle components for safety brakes and transmissions
• Missile components
• Naval engines, structural systems, and vessel components
• Optical sensors
• Rotor hubs and other helicopter components
• Tire valve stems
• Track hubs for tanks and other tracked military vehicles

Although many of these items can be made via less advanced CNC and even traditional machining, military manufacturers benefit from the accuracy and speed that 5-axis CNC machines can provide.

The Staub Difference: 5-Axis CNC Machining for Military Components

Staub Precision Machine Inc. understands the need for precisely machined components and other assemblies for the defense industry. As a partner, Staub is intimately familiar with the need for durable components for military equipment. We understand the rigors of the battlefield and the harsh treatment the parts and components we make for the defense industry must endure. With Staub’s 5-axis CNC machines, we can help our customers provide robust and dependable products to the defense industry.  

Examples of what Staub’s 5-axis CNC machines can make include: 

• Blade cutters for cutting through cabling
• Cable clamp components in aircraft systems
• Parts for optical signal encoders

These are just a few components Staub has the capability to produce. The defense industry requires flawless parts for its equipment, which must withstand all the rigors of the battlefield and other extreme environments. For this reason, manufacturers like Staub need to register with the US State Department’s ITAR (International Traffic in Arms Regulations) and maintain compliance with other standards used within the defense industry, like AS9100 and ISO 9001:2015. To learn more about Staub’s 5-axis CNC machine capabilities in manufacturing for the military and other industries, contact us today.