Plastic machining is one of the most common industrial processes due to the high usage of this material. However, modern-day plastic CNC machining isn&#;t what it used to be. Plastics nowadays can be built strong enough to stop a bullet&#;s impact. This calls for a very rugged machining method.
For more information, please visit our website.
CNC machining plastics has become a great solution for these requirements. Plastics have a lot of variety, with differences in physical properties and chemical structure. All of these varieties are easy to machine with CNC machining.
This article will explore the applications of CNC machining of plastic materials. It will go into the details of different kinds of CNC machined plastic parts and their physical properties. You can decide which plastic materials best suit your job requirements based on the information provided here.
What is Plastic CNC Machining?
Plastic CNC Machining is a CNC machining process that uses Computer Numerical Control (CNC) technology to automate machining of plastic materials. This is achieved through computer programming guiding the machine tools.
While CNC machining technology supports a variety of materials, such as metals, alloys, glass, wood, and ceramics, this specific term refers to its application in plastic machining.
Can Plastics Be CNC Machined?
Yes, CNC machining plastics is possible. In fact, CNC machining is the best way to make plastic components. This is because of the high accuracy and speed of this process. The quality of plastic CNC machining is way ahead of other alternatives like injection molding or 3D printing.
What Are the Common CNC Machining Plastics?
Any plastic can undergo CNC machining. Some common plastics that use this process are:
Nylon has good chemical resistance and heat resistance. Therefore, nylon usage is commonly found in applications such as insulations and sheaths. Nylon spacers are used in circuit breakers for the electronics sector. Commonly used processes on nylon are CNC mills and lathes. There are many different grades of nylon. Nylon 6/6 is a common type used in plastic CNC machining.
Polyethylene is also known by its common name Polythene. It is the most commonly used and produced plastic type. The high popularity of polythene has led to the emergence of several different types. Two of the commonly found polythenes for plastic CNC machining are LDPE and HDPE.
LDPE has low tensile strength, high ductility, and low density. Common applications of LDPE are for making trays and foils in the packaging industries. It has very low moisture absorption.
HDPE has better physical properties than LDPE. The main attractive points of HDPE are its high density and tensile strength. Plastic bottles and pipes are made of HDPE material.
Polyethylene Terephthalate (PET) is in the subclass of polyester plastic materials. It is the major constituent of packaging in the food and beverage industries. It is a hygienic, water-resistant, and lightweight material. It is also one of the easy-to-machine plastics used in plastic CNC machining projects.
PVC is one of the most popular plastics used for its high strength. It is a very durable material with high tensile strength, lightweight nature, and chemical resistance. There are many different forms of PVC available for different applications.
Chlorinated Polyvinyl Chloride is derived from PVC itself. CPVC is obtained after successive chlorination of PVC resin. CPVC has improved properties than PVC plastics. The purpose of CPVC is to eliminate the vulnerability of PVC to temperatures during the plastic CNC machining process.
Polycarbonate is a type of thermoplastic polymer. More than one billion kg of Polycarbonate is manufactured annually. This is because of the high-grade physical properties and widespread PC applications.
Polypropylene is also known by its common name Polypropene. It belongs to the thermoplastic polymer category. Its properties are a slight improvement to polythene.
Disadvantages of PP
Polyphenylsulfone is an aromatic ring polymer. It is an easy-to-machine plastic. It is also moldable with injection molding. It is a high-performance thermoplastic.
Polysulfone is another high performance thermoplastic like PPSU. PSU parts can be used in a wide range of temperatures. Common range is -100°C to 200°C. The temperature range makes them one of the highest service temperatures of plastic.
PPS is known by a lot of different names due to various brands manufacturing it. Some common brand names are Durafide, Petcoal, Ecotran, and Fortron. It is a high temperature thermoplastic polymer.
PEI is an amorphous thermoplastic. Its color spectrum can vary from amber to transparent. It provides a cheaper alternative to PEEK thermoplastic with similar properties.
Ultra-high molecular weight polyethylene is a subtype of Polyethene thermoplastic. It also goes by High Modulus Polyethylene (HMPE). It has a good load-handling capability due to long-chain polymers.
Acetal is one of the most used plastics in CNC machining. It also goes by its other name Delrin. It is a very easy to machine plastic.
Let&#;s explore some of the Delrin machining characteristics.
Polystyrene is a solid of foamed polymer. The foamed variety has been patented and the trademarked name goes by Styrofoam. Styrofoam is actually an Extruded Polystyrene (XPS). DuPont owns the trademark of styrofoam and manufactures it globally. 98% of styrofoam is air, leading to its foamy nature.
ABS is another popular CNC machining plastic. It is a thermoplastic polymer. It has impressive physical properties which lead to a lot of applications find different industries.
Carbon fiber is basically Carbon Fiber Reinforced Polymers (CFRP). It has thin strands of carbon fiber added to a base plastic for improved properties. It is classified as a composite material.
Teflon is a brand name of polytetrafluoroethylene. It is patented by Chemours. Interestingly, Teflon was also discovered by DuPont, which already holds the trademark for Styrofoam. Chemours was branched from DuPont and is the global manufacturer of Teflon.
Let&#;s get into more details of using Teflon for CNC machining.
PMMA goes by a lot of different names, such as Acrylic and Acrylic Glass. Many other brand names exist, like Lucite, Plexiglass, Perclax, Perspex, etc. Its high transparency is why Acrylic finds many applications in machining, replacing the traditional glass.
Polysiloxane is a colorless, rubber-like substance also called Silicone. It is used for many plastic CNC machining applications in electronics, household, electrical, automobile, and aviation manufacturing industries.
Poly Paraphenylene Terephthalamide usually goes by its common names kevlar and twaron. It is one of the most popular aromatic polyamides globally. It is a synthetic fiber developed by DuPont. Its physical properties are comparable to or even better than metals and alloys.
Celcon is a high-performance acetal polymer that works in a wide range of temperatures. It is resistant to most adverse conditions and has a long service life. There are many subtypes of Celcon, like UV-resistant, wear-resistant, glass-reinforced, bleach-resistant, impact resistant. etc.
PPO is a high-temperature thermoplastic. It is a hard-to-manufacture material. Therefore, it is generally used in its blended form. It is also known as Polyphenylene Ether (PPE). It has quite good performance characteristics. It is mixed with Polystyrene to improve its physical chacteristics.
Kapton is a special type of polyamide film. DuPont invented it. It has one of the best temperature handling amng all plastics. It can sustain temperatures between -269°C to 400°C.
PES plastic is available in blocks, sheets, and rods. It is also sometimes referred as PESU. These plastics have great physical properties and temperature handling. The color of PES is reddish brown with good transparency.
PVDF is a chemically inert thermoplastic. It is a special kind of plastic used in very niche applications. The main use case for this plastic is when a highly non-reactive material is required. PVDF can resist any chemical. It can be obtained in many different forms, like pipes, sheets, powder, tubes, plates, and films.
TPE is also sometimes termed as Thermoplastic Rubber. It is a mix of different polymers, often plastic and rubber. TPE is different from conventional elastomers, which is thermosetting in nature. However, the thermoplastic properties of TPE allow the application of many different manufacturing methods.
TPU is a wide class of Polyurethane (PU). It can exhibit a range of different properties. It is easy to machine with CNC, extrusion, and injection molding. It can also be shaped with calendering. Due to the wide range of manufacturing processes, TPU scrap can be recycled over and over.
PEEK is a very popular CNC machining thermoplastic. It is colorless in pure form. Its melting point is 343 °C, which makes it good for high-temperature applications. Operating temperatures of many PEEK subtypes easily go up to 250 °C.
What CNC Machining Process is Most Suitable for Plastics?
All CNC processes work well for plastic CNC machining. CNC mills and lathes are some of the most common machines used for these materials. Other processes like CNC drills and waterjet cutters also provide good results for plastic machining.
Applications of Plastic CNC Machining
There are many use cases for using CNC machining for working on plastic materials. Some of these applications are:
Plastics are used for making a lot of different parts in the automobile sector. Interior parts such as linings, handles, and dashboards are plastic. Even exterior components like bumpers use plastics. Other miscellaneous plastic components are engine covers. electronics housing, etc.
The chemical resistance of plastics has many applications in the oil and gas industry. Plastics make seals and containers for oil extraction and storage. Electrical connectors in heavy mining machinery are also made of plastic.
Plastic is used extensively in the food processing industry as a primary and secondary packaging material. Food-grade plastic containers are machined with CNC to provide a safe storage option. CNC-made plastic trays provide an impact-resistant transportation option for food items.
Plastics are widely used in the agriculture sector for a variety of equipment. They are applied for making irrigation and drainage solutions. Plastics are applied for making sillage and nets. Agricultural components like greenhouses, planters, and tools also increasingly use plastics.
Several plastics have a high impact and corrosion resistance. This makes them ideal for making parts that face extreme pressure, like valves and pumps. Plastics like thermosetting polyimide also make structural components for the aerospace sector.
CNC-machined plastics are used for making implants and many other devices. Electronics enclosures of medical devices like pacemakers, vitals monitoring, and others are made with high-grade plastics. Many plastics have a wear-resistant surface and resistance to stress cracking. This is why they are beneficial for making implants.
If you are looking for more details, kindly visit kaierwo.
Cases of appliances like TV, laptops, and smartphones are made with CNC-machined plastics. These CNC machines are accurate and provide the consistent results required in this sector.
How to Choose the Right Plastic For Your CNC Project?
There are many different plastics to choose from for whatever you manufacture. The choice of plastic should be done by evaluating the various parameters that influence the decision. Some of these factors are:
Where to Find a Good Provider For Plastic CNC Machining?
Getting a CNC machine can be a very costly investment. This is why there is a new trend where manufacturers choose to outsource the CNC machining of plastic materials.
3ERP is the market leader for plastic CNC machining services and parts. 3ERP&#;s CNC machined plastics are high-quality parts that work better as intended. 3ERP uses the most advanced CNC machinery to fulfill any complex requirements that you might have. The manufacturing time is quite low, and you get your parts as soon as you require them. Contact 3ERP to get a quote for your project.
Endnotes
CNC plastic machining is the go-to process for plastic materials when quality and precision are important. Injection molding fails tremendously in terms of consistency and precision. Additionally, additive manufacturing techniques work only for plastics that can be molded by heat. If you want to use plastic material for your next project, 3ERP CNC plastic machining services can be the perfect fit.
Frequently Asked Questions (FAQs)
Polyamideimide is the strongest plastic for CNC. It has a tensile strength of over 21,000 psi. Even with this extremely high strength, it is easy to machine with a CNC.
Polyethylene (PE) is the cheapest plastic for CNC machining. Known for its affordability and excellent machining properties, PE is used widely in a variety of applications, including wear strips, gears, and consumer goods.
Acetal (Delrin) is the most commonly used plastic for CNC machining. It offers superior strength, stiffness, and dimensional stability, making it a popular choice for precision parts in automotive, electronics, and industrial machinery applications.
PEEK (Polyether Ether Ketone) is among the hardest plastics to CNC machine. Its high thermal and chemical resistance, along with its strength, makes it difficult to machine but desirable in demanding environments like aerospace or medical fields.
ABS (Acrylonitrile Butadiene Styrene) is typically the easiest plastic to CNC machine. Known for its excellent machinability, ABS is used frequently in prototyping and manufacturing applications due to its ease of use and strong, durable properties.
Share this blog:
CNC machining is a versatile and efficient process that countless companies use to produce their pieces and parts. This high-precision, high-quality, and fast-paced production process can accommodate a wide range of different materials.
Metals, woods, composites, and plastics are all suitable for machining, and among them, plastics are one of the most common. But there are many types of machinable plastics, so how do you choose the right one?
It&#;s not an easy question to answer, and it depends on a range of different factors. This article will explain the properties you have to keep in mind while working with plastics and give examples of the most common plastics used.
4 Factors to Consider When Choosing a PlasticAs we explained in our article about CNC machining materials, the physical properties of a material affect its machinability. As such, the results you can obtain from your workpiece will vary by material.
With plastics, the size and shape of your workpiece can change during or even after machining. As such, design engineers need to take material properties into account to ensure the manufacturability of their design. Next, we&#;ll explain the various factors you should consider.
#1 Thermal Expansion and Heat Deflection Temperature (HDT)Almost every material expands and gains volume at high temperatures. In CNC machining, the tooling used produces heat when it contacts the material.
In the case of plastics, their coefficient of thermal expansion is higher than metals. As such, they can exhibit a more significant change in size as a result of machining.
Therefore, it is crucial to understand how each plastic reacts to heat input from machining. You should also consider the amount of heat exposure the plastic will receive. These factors will impact the ability to meet dimensional tolerances.
Additionally, a material&#;s heat deflection temperature (HDT) indicates when it will start to deform easily due to exposure to elevated temperatures. When making your final materials selection, you may need to consider this to ensure the part is suitable for its intended application.
#2 Hardness and StrengthThe hardness and strength properties of a specific plastic may be something you are considering for your part to make sure it stands up to the requirements of its final application. However, these properties also affect the way a material behaves during machining.
The tensile strength of a material can impact how it forms chips, affecting the final surface finish. Hardness can also affect the way chips form, and for very soft materials, gouging can occur if the operator does not take suitable precautions.
Furthermore, the hardness and tensile strength of a material can impact the wear life of the tooling used. However, this is generally a more significant consideration when machining metals and ceramics.
#3 Moisture Absorption and Reaction to ChemicalsCertain plastics can absorb moisture from the air or coolant or can be detrimentally affected by certain chemicals. They may even need to be kept in air-conditioned rooms or sealed bags.
The effects of moisture and chemicals can cause the dimensions of the material to change, affecting the ability to meet precise tolerances. They can even degrade the strength and stability of the plastics altogether.
#4 Appearance, Transparency, and Light TransmittanceAppearance and associated properties, such as light transmittance, may be an essential aspect of your design. If so, this limits the number of plastic materials available to you. Furthermore, care will need to be taken with the machining process to ensure a rough surface finish does not impact light transmittance or transparency.
Top 10 Plastics Used in CNC MachiningBased on the factors described above, you may be wondering which machinable plastics are best and how to apply those factors to which plastic you should use for your project?
Luckily there are plenty of applications for CNC machined plastics, including in medicine, automotive, aerospace, electronics, clothing, technology, and even building construction! In the table below, you&#;ll find 10 of the best machinable plastics:
Name Chemical Name Description Advantages Disadvantages Applications ABS Acrylonitrile Butadiene Styrene A Terpolymer made by polymerizing styrene and acrylonitrile. Thermal and chemical stability and good strength. Can be harmful if heated to above 400ºC. Control panels, pipes, keyboards, etc. Acetal/POM Polyoxymethylene A thermoplastic that is highly suitable for producing high hardness precision parts. Low moisture sensitivity, high resistance to chemicals, good electrical resistivity, high hardness. Sensitive to acid hydrolysis and oxidation by chlorine. Mechanical gears, screws, bobbins, telephones, televisions, etc. Acrylic/PMMA Poly(methyl methacrylate) A transparent thermoplastic. Transparency, tensile and flexural strength. Poor impact resistance, limited heat resistance, and low chemical resistance. Light lenses, intraocular lenses, artificial teeth, etc. Nylon/PA Polyamides A silk-like thermoplastic, it can be melt-processed into a variety of shapes. Good elasticity, can be washable and dyeable, and resists high levels of heat. Low absorbency, pollution problems, lack of stability. Washers, gaskets, wheels, wear-resistant barriers, etc. PC/Polycarbonate Polycarbonate Group of thermoplastics that can produce durable materials with high-impact resistance. Good stiffness, highly transparent, and good thermal resistance. Low scratch resistance and can expand. Electronics, roofing sheets, compact disks, automotive and aircraft parts, etc. PEEK Polyether ether ketone A semicrystalline organic thermoplastic, useful in several advanced engineering applications. Very good strength, heat resistance, and chemical resistance. Expensive relative to other plastics, and with poor UV light resistance. Aerospace and automotive components, pumps, bearings, medical implants, etc. PET Polyethylene terephthalate A colorless and semi-crystalline thermoplastic polymer resin. It can be semi-rigid or rigid, and is also very lightweight. Good strength and stiffness, low moisture sensitivity, fully recyclable. Thermal sensitive, fair HDT, fair moldability. Soft drinks bottles, solar cells, frozen food trays, magnetic tapes, etc. PVC Polyvinyl chloride A synthetic plastic polymer available in a rigid form (RPVC) or flexible form. Good mechanical strength and toughness, and good chemical resistance. Poor heat stability, can emit toxic fumes when melted or exposed to fire. Window frames, drainage/water pipes and valve components, etc. HDPE High-density polyethylene Thermoplastic polymer produced from ethylene. High strength and stiffness, low moisture absorption, and good chemical corrosion resistance. Sensitive to stress cracking, sensitive to oxidizing acids, high thermal expansion, and highly flammable. Chemical tanks, cutting boards for food preparation, orthotics and prosthetics, etc. FEP Fluorinated ethylene propylene Copolymer similar to PTFE and PFA resins. FEP is highly transparent and resistant to sunlight. Low coefficient to friction, good stress crack resistance, and chemical resistance to a wide range of solvents. Very sensitive to stress and limited strength. Chemical equipment, food processing equipment, and various low friction parts.
There are many other machinable plastics, so inquire with our service experts if you want to use a different material!
Which Plastic Should You Choose for Your CNC Project?As you may have realized, there is a wide variety of CNC machinable plastics available. But, which is best for your project?
If you are looking for a strong plastic with transparency properties, you may want to choose between PC, Acrylic, or PET, though you should keep in mind their thermal limitations.
Maybe you need something with good chemical resistance? If so, CNC machining your product from ABS, PEEK, POM, PVC, HDPE, or FEP may be an excellent option.
It really depends on your goals for the part. And if you want assistance deciding which material is best for your application, our experts can provide insightful advice for you to make sure your project turns out just right!
The company is the world’s best cnc machining plastic service supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.