A&M provide accurate and fast CNC milling services, supplying components for various for notable clients in industries such as automotive, nuclear, marine and aerospace.
CNC milling is a machine process used for making parts by progressively removing material from a workpiece by rotating multi-point cutting tools which are operated by a computer-controlled programme.
Originally, milling was a manual task performed by engineers using handheld tools. This did, however, increase the likelihood of errors and meant a slower production time.
Today, technology has progressed to the CNC mills we have at A&M.
These use Computer Numerical Controls (CNC) to control the milling operations, improving accuracy to ensure the exact dimensions specified are met.
CNC Milling Process
A CNC milling job incorporates several stages. First, a CAD (computer-aided design) model must be produced, which provides the CNC machine with a technical drawing of the workpiece. Our highly equipped design engineers convert the CAD model into a CNC program, to ensure the milling machine knows the precise dimensions required for the component.
The milling machine is then set up and programmed, and the milling operation takes place. The length of the process depends on whether a component is being manufactured from start to finish, or if it just a finishing operation.
We provide both options and depending on the size and scale of the workpiece, we will discuss the turnaround time.
Roughing is the initial step of the milling process; cutting small pieces from the worked object to form the approximate shape or form desired.
Finishing completed the job, going from approximate to precise. The milling is more delicate when finishing and can take several repeats until meets the specifications are met. The more complex the job, the more milling repeats will be required. But with our milling machinery, we can guarantee the components will match specifications.
3, 4, 5-Axis Milling
A&M have an extensive range of CNC milling machines available with 3 to 5 axes. The X-axis and Y-axis represent horizontal movement (side-to-side and forward-and-back), and the Z-axis represents vertical movement (up-and-down).
The W-axis represents diagonal movement across a vertical plane. In more basic CNC milling machines, horizontal movement is possible in two axes (XY), whilst in our advanced models, there are several additional axes of motion, such as 3, 4, and 5-axis CNC machines.
These are some of the advantages of each milling machine:
• Most metal machining needs
• Suitable for cutting sharp edges, drilling holes, milling slots
• Simplest machine setup
• Greater range of materials including aluminium
• Greater functionality than 3-axis machines
• Higher levels of precision and accuracy than 3-axis machines
• Multiple axes configurations (e.g., 4+1, 3+2, or 5)
• Suitable for advanced precision work for example aerospace components
• Greatest functionality and capabilities
• Faster speeds than 3-axis and 4-axis machines
• Highest levels of quality and precision
Developing Tooling Techniques
At A&M, we have made major efforts to maximise the effective potential of our Hurco machines, having invested in Shrink Fit and tool holding technology to improve the tool life and reduce set up times allowing faster repeat operations.
Our research also enables us to predict the life cycle of a tip before it breaks resulting in fewer tool breakages. Applying this analysis has seen production times reduced by 40% and allows us to run milling machinery overnight without supervision, which is crucial to us meeting production deadlines.
CNC Milling Frequently Asked Questions
The CNC milling process typically begins with the design stage: using CAD to draw out a 2D or 3D model of the desired product. Following this, the CAD will be converted into instructions which can be read by a computer (a CNC programme).
Once the milling machine and workpiece are prepared, the CNC programme can be activated, allowing for the machining of the workpiece.
A CNC milling machine is used to conduct CNC milling services; this is a reductive operation – removing pieces from a workpiece to create a desired shape. CNC is a common abbreviation for Computer Numerical Control; this means the operation is programmed by CNC milling software to mobilise either tooling or a workpiece, perhaps both, so that the workpiece can be machined.
There are a variety of CAD and CAM software packages available for CNC milling. Some of the most popular include: Autodesk Fusion 360, SolidWorks, AutoCAD, and Inventor.
CNC milling advantages include: being controlled by software, CNC milling is precise and fast with high levels of repeatability across products. The machines can be run for long hours, and are compatible to work with a variety of materials. CNC milling also enables complex designs and shapes. There is the ability to update the machine through software, maintaining competitiveness and relevancy as a manufacturing method.
CNC milling disadvantages include: CNC milling requires trained operators, which may subsequently lead to the loss of skill in manual machining methods; CNC machines are initially expensive to purchase and set up, though they are generally affordable as a manufacturing method; scrap material is produced since milling is a reductive operation.
A CNC milling spindle is located within the rotary unit – and sometimes may be used in reference to the entire rotary unit. It rotates on an axis, holding the tooling which is used to cut a workpiece. This is generally an electrically powered device.
CNC milling gear cutting refers to the creation of gears with a CNC milling machine. A milling machine is capable of removing material from a metallic workpiece to create the desired shape of a gear, being a precise and controlled manufacturing method.
CNC milling gear grinding is a finishing stage in the production of gears on a milling machine. Cutting tools can be exchanged for more abrasive tooling which is used to grind the surface of the gear, removing excess material.
CNC milling gear shaping refers to the machining process used to cut teeth into the gear; this usually occurs with a multipoint cutting tool. The ability to rotate the workpiece on a milling machine allows for consistency in the teeth around the perimeter of the gear.
The most common materials that can be CNC milling machined include metals.
- CNC milling aluminium; aluminium has great machinability, and is a strong material with good corrosion resistance.
- CNC milling steel; both steel and stainless steel can be CNC machined. Steel is often used for high stress applications, whereas stainless steel is often used to achieve an aesthetic.
- CNC milling graphite; graphite has high conductivity and corrosion resistance, however can be difficult to machine because of its abrasiveness.
Plastics are moreover compatible with CNC milling machines.
- CNC milling acrylic; acrylic is lightweight and durable, however can crack when stressed. It is still suitable for CNC milling despite this.
- CNC milling foam; foam, an expanded plastic, can be machined. This is often used for prototypes, since the material is inexpensive.
- CNC milling nylon; nylon has good machinability and moderate fire resistance, making it a suitable material for a variety of applications.