A Deep Dive into CNC Milling
CNC machining is a highly automated manufacturing process that uses a computer to control machinery. The desired geometry and requirements of the final product are entered into a special software called CAD (Computer Aided Design). Then, the software is used to control machinery operating conditions such as speed and location. The computer directs the CNC machine to execute the desired cuts with the machine operating like a robot.
CNC precision machining is a cost-effective solution that enables the fabrication of high-quality, complex parts that would not be feasible with conventional machining methods. The remainder of this article will focus on one of the most common CNC machining operations: milling.
The CNC Milling Process Explained
A CNC milling machine is a form of subtractive manufacturing that begins with a block of raw material – typically metal, wood, or plastic – and the material is cut and carved as necessary to achieve the desired geometry. CNC milling is a highly versatile machining method that is known for its precision and ability to achieve complex designs with tight tolerances.
There are various CNC milling machines on the market but nearly all are comprised of the same key pieces of equipment: a work table, cutting tool, and spindle. The block of raw material is typically fastened to the work table. The cutting tool is held in place by a spindle which, for most CNC milling machines, is rotated by an electric motor during cutting operations. The cutting tool, or cutter as it is often called, is used to mechanically perform the carving. One of the most common tools is a milling cutter, which is similar to a drill bit but has many “teeth” that are designed to remove material in a specific way. Cutters come in a variety of shapes, sizes, and arrangement of teeth, each providing a unique cut. As the milling cutter contacts the work piece, the teeth of the tool repeatedly cut the material, shaving off chips from the work piece with each pass. The milling process removes material by performing many separate, small cuts. Operating conditions such as the feed rate and cutting speed can be adjusted as necessary to achieve the desired cut during CNC milling. State-of-the-art CNC milling machines may also include advanced equipment such as remote tool changers, tool carousels, and robust coolant systems to improve operations efficiency.
Proper tool selection is a key aspect of successful CNC milling. Tools are typically designed to provide a unique cut and for use with a certain raw material. Choose the wrong tool and you may damage the work piece or even the tool and CNC machine. In general, smaller cutting tools take longer to complete the desired cut but are able to deliver more complex and intricate designs. Ideally, each milling job would only require a single tool, however, most parts require multiple tools to achieve the desired design. Another component of tool selection is balancing – and in most cases minimizing – machine time in order to complete the part as fast as possible without sacrificing quality. For these reasons, it is crucial to select the right tools for each job and rely on the expertise of a trusted CNC milling partner, like ABS, that guides customers through the design process and offers a wide array of CNC machining solutions.
There are two main types of CNC milling machines that are categorized based on orientation: vertical and horizontal. As the name implies, vertical machines are oriented to perform cutting “up and down” in a vertical motion whereas horizontal machines perform cutting horizontally. There is variety within both types of milling machines; for example, spindles and work tables can either be stationary or move along a number of axes, depending on the specific CNC milling machine being used. In general, vertical mills are often considered more versatile while horizontal mills are typically used for heavier or longer parts that require deeper cuts. Some key factors to consider when deciding between a vertical or horizontal milling machine include the size and geometry of the part as well as the number of surfaces that require cutting. Additionally, universal CNC milling is another type of machine that is able to accommodate a horizontal or vertical spindle depending on how the machine is setup. Universal machines offer machine shops additional CNC machining flexibility.
Looking for trusted CNC milling partner for your heavy fabrication?
Contact the team at ABS to learn about the range of CNC machining solutions we offer including our 5-axis machining.
One feature that sets CNC milling machines apart from traditional methods is its ability to move along a number of axes, ranging from 2 to 5 axes. Most traditional CNC milling machines are able to move along 3 axes: the X-, Y- , and Z-axes at the same time. 5-axis CNC milling machines are able to operate along these 3 axes as well as 2 additional rotational axes, A- and B-, for a total of 5-axes working simultaneously. In general, the more axes a CNC machine can operate on, the more intricate geometries it can fabricate. Thus, 5-axis machining has a huge advantage over traditional CNC machines and are able to manufacture complex parts that may not be possible with conventional machines.
At ABS, we offer a range of CNC machining options and tailor our solutions to meet each customer’s specific application. Our team has extensive experience with CNC milling including gantry milling and boring milling. A CNC gantry mill is unique in that it has a structure that bridges over the work area. These mills can be fixed but most often have a milling head that moves on a set of parallel rails. The rails provide accurate motion for the moving machine and are strong enough to support the weight of the machine and accompanying equipment. CNC gantry milling is most often utilized for parts that rely on the X- and Y- axes.
As noted, ABS also offers CNC boring milling. These machines have a cylindrical cutting tool that rotates to create a broad range of shapes, slots, holes and other cuts. CNC boring mills can handle extremely large parts and offer excellent precision. The ABS fleet of CNC boring mills, vertical turning lathes, and table type boring mills are supported across our six facilities and serviced with cranes with lifting capacities up to 160 tons.
About ABS
Established in 1971, ABS Machining has grown to become the recognized global leader in large CNC machining, fabrication, and assembly for OEMs. The key to our success has been exceptional people, unparalleled facilities, and an unwavering commitment to quality. Our people are experts in their given field. Their expertise is matched only by their passion for serving our clients. We continue to invest in our people with education programs, cross training and in our internal accredited apprenticeship center.
Our facilities are state-of-the-art and we are equipped to serve our client’s requirements in:
Our massive fleet of machines and automated welding systems has delivered solutions to the most technically challenging projects. Our commitment to maintaining unparalleled facilities is evidenced by our renowned continuous capital reinvestment initiatives. Our commitment to quality goes well beyond our ISO 9001:2015 Registration. From the inception of all programs, ABS quality professionals work closely with each customer to ensure all their unique requirements are met or exceeded. It is this commitment that has positioned ABS as a strategic supplier to leading OEMs worldwide.
Contact us today to see how we can help with your machining project, or give us a call at 1-844-227-6224.
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