XavierBenefits of CNC Plastic Machining
CNC plastic machining has earned its place because of its specific advantages. While there are many ways to machine plastics, from commodity resins to high-performance thermoplastics, computer numerically controlled (CNC) plastic machining has quickly become the technology of choice for producing tight-tolerance plastic parts.
Before you understand what benefits CNC plastic machining can bring, you must go back to basics and gain a deeper understanding of what CNC plastic machining is all about.
1.What is CNC Plastic Machining?
CNC plastic machining is a subtractive manufacturing process that involves cutting solid blocks of plastic and creating parts. To understand the process of CNC plastic machining, let’s take a look at some of the most common methods below.
2.CNC Plastic Machining Methods
CNC machining uses computer-generated and controlled machines to remove certain parts of plastic polymers to create specific products. Therefore, it ensures uniformity, accuracy, and high tolerances.
The methods involved in manufacturing the final product include:
1) CNC Turning
This is a special technique where the workpiece is fixed on a lathe and the plastic is rotated or spun against a cutting tool.
Under this method, there are two types of turning: cylindrical or linear CNC turning, which is suitable for fairly large cuts, and tapered CNC turning, which is best used for tapered linear shapes. Depending on what you are working on, the type of CNC turning method may vary.
2) CNC Milling
Another method of CNC machining is called milling. This method utilizes a milling cutter to shave off specific parts of a workpiece to produce the desired result. Much like CNC turning, there are also different types of milling methods to choose from, which can be divided into two types of milling: three-axis milling and multi-axis milling.
As the name suggests, a three-axis milling machine can move along three axes, mainly left and right, up and down, and front and back. Therefore, it is best suited for projects with simple designs. On the other hand, a multi-axis milling machine can move more dynamically, making it a great solution for more complex geometries.
3) CNC Drilling
Plastic drilling uses a drill bit to make a hole in the workpiece. The size and shape of the hole depends on the type of drill bit used.
4) CNC Broaching
Related to drilling, if you don’t have the right drill bit but want to enlarge a hole you’ve already drilled, you can try a process called broaching. This can effectively enlarge the diameter of the hole while improving the overall quality of the plastic surface.
3.Different Plastics Used in CNC Machining
One of the reasons why CNC machining is so popular across industries is that it is compatible with a wide variety of plastics. As a result, many businesses can manufacture plastics at a more convenient rate than other alternatives.
Take a look at some of the most common plastic materials used to complete this process.
1) Polyetheretherketone (PEEK)
PEEK is a high-performance thermoplastic that is popular for its unique combination of mechanical and chemical properties. This plastic can resist chemicals, fatigue, liquids, and abrasion. Additionally, it can withstand temperatures up to 480°F.
Aside from that, PEEK is lightweight, durable, insoluble in common solvents, and strong enough to withstand harsh conditions. Overall, PEEK is an ideal material when it comes to CNC machining.
2) Acrylonitrile Butadiene Styrene (ABS)
Another popular thermoplastic in the engineering field, ABS is known for its heat resistance, impact resistance, and impeccable processability. It is a good insulator and maintains mechanical stability over time, which makes it an excellent choice for electrical applications.
Similar to PEEK, this plastic is also strong and lightweight, but it is not resistant to abrasion, solvents, or alcohol. ABS is flammable unless treated with heat stabilizers. It is important to keep this information in mind when choosing the best material for your project.
3) Polyamide (PA)
Commonly known as nylon, this material is a low-friction thermoplastic that has high impact strength, chemical resistance, and abrasion resistance. It also has excellent mechanical properties. Because of this, it is well suited for a variety of applications in industries such as medical and automotive.
4) Polyoxymethylene Polyoxymethylene (POM)
Commercially known as Delrin, POM is considered one of the easiest CNC plastics to process, especially when a business needs a plastic that is extremely resistant to wear, weathering, heat, fuel, and chemicals, high strength, and high stiffness.
In addition, POM is also an excellent choice for product teams to manufacture precision parts because of its excellent dimensional stability.
5) Polytetrafluoroethylene (PTFE)
PTFE is a high-performance polymer and a versatile plastic that is resistant to chemicals, light, temperature, water, weathering, fatigue, corrosion, and UV rays. It is also known for its excellent anti-sticking properties.
Because of this, it is most commonly used in kitchen appliances as well as many other semiconductor components.
4.Advantages of CNC Plastic Processing
In addition to being compatible with a wide range of plastics, CNC processing offers many benefits to users.
1) Precision and Accuracy
One of the advantages of this manufacturing process is its ability to manufacture plastic products with extremely high precision and accuracy. Since the machine relies on computer-generated designs, it only follows a specific process. What’s more, it has tight tolerances, leaving little room for error.
2) Prototyping Support
Another advantage is that CNC machining supports prototyping. With its accuracy and precision, you’ll be able to produce and replicate the same product in large quantities. Even if your design has complex shapes, CNC machining can produce large quantities of products with the same shape and size and the same high quality.
3) Cost-effectiveness and speed
Whether you plan to produce small or large batches, CNC machining is one of the most cost-effective solutions you can explore. Unlike other traditional methods that may require a series of manufacturing processes and consume a lot of time, CNC machining can do everything you need in one go. What’s more, it’s fast and efficient.
5.Applications of CNC Plastic Machining
As a versatile plastic manufacturing process, CNC machining is an excellent choice for businesses in different industries. Here are some of the industries that use this solution most often.
1) Aerospace
Making aerospace parts requires high accuracy, precision, and tight tolerances. Therefore, the industry relies heavily on CNC machining to design, test, and manufacture a variety of aerospace products.
Besides being able to guarantee precision every time it is produced, CNC machining also allows for the use of lightweight, heat-resistant, chemical-resistant, and durable materials that are essential in this particular field.
2) Medical
CNC plastic machining is also applicable in the medical field. The process is often used to manufacture medical devices such as artificial hearts and prosthetic limbs. The repeatability and high precision of CNC machining meet the strict safety standards of this industry.
In addition, its rich material selection and ability to produce complex shapes make it a beneficial method in the medical field.
3) Automotive
Engineers and automotive designers use CNC machining to prototype different automotive parts in real time. It enables them to customize each part and see how each part will fit. With its lightweight materials and heat-resistant properties, CNC plastic machining can help automotive designers create efficient and practical parts.
4) Electronics
The electronics industry also favors CNC machining, mainly because of its repeatability and high precision. Experts in this industry can easily develop plastic electronic components such as device keyboards, LCD screens, and wire housings.
While CNC plastic machining is an effective method to accommodate a wide range of applications in various fields, you can also explore other alternatives such as injection molding.
In contrast to CNC machining, injection molding is the process of shaping or reshaping plastic pellets by injecting a heated substance into a mold. It is applicable to a variety of plastic materials and industries and is an excellent alternative to CNC machining.