Nylon is one of the most useful materials worldwide, and we see it basically everywhere. This is because of the vast majority of benefits it offers especially in CNC applications, but what exactly is nylon machining, and how does it benefit you?
What Is Nylon Machining?
Nylon machining is the use of industrial nylon machining tools to cut nylon into smaller and more suitable parts. This is important because nylon, also known as polyamide, has a variety of properties that make it suitable for several industrial processes.
Types of Nylon Befitting for Machining
There is a wide variety of nylon for machining because of their innate properties. Here, we discuss nylon suitable for machining.
Nylon 6
Nylon 6 is one of the most popular nylon in use because of its many sought-after properties. It has a very high tensile strength, resistance to shock and impact, as well as being easy to machine. It can also be woven, making it suitable for manufacturing carpets, seat belts, clothing, ropes, and industrial cords.
Nylon 66
Nylon 66 is a type of polymeric nylon with a nitrogen atom separating two segments of nylon 6 molecules. This particular nylon is unique because of the presence of hydrogen molecules in the structure, making hydrogen bonding possible for increased tensile strength and thermal stability.
These above properties make nylon 66 a suitable choice for manufacturing materials with the ability to resist tears and snaps such as fishing lines, sutures for surgical use, climbing ropes, conveyor belts, and several others.
Nylon 11
Nylon 11 is another type of polymer polyamide belonging to the nylon family. It is made mostly with natural renewable materials which gives it an edge compared to other synthetic nylon. These advantages include high heat resistance, resistance to chemical corrosion, and, most importantly, low water absorption and resistance to water and oils.
The above properties make nylon 11 a perfect candidate for applications such as tubing. They are also used in sheathing electrical cables and in making coatings.
Nylon 12
Nylon 12, also known as PA 12, is a notable member of the nylon family that is highly versatile. This feature lies in its unique flexibility and very high tensile strength. This makes nylon 12 ideal for making materials exposed to constant stress and repetitive usage cycles. Nylon 12 has also found use in the cosmetic industry, as well as the textile industry.
Nylon Properties That Made it Suitable for Machining
Nylon has many properties, which makes it desirable for its use in CNC nylon machining compared to many other materials and metals. Below are some of these beneficial properties that give it an edge over others:
Mechanical Properties
Nylon has excellent mechanical properties, which make it great for a variety of manufacturing processes. This lies in the fact that:
- Nylon has an incredible tensile strength of about 40 – 100 MPa, making it resistant to breaking under tension
- Nylon has an elongation at break, which measures the ability to resist deformation and cracks of up to 5 – 120%
- It has a variable heat Deflection Temperature (Melting point), depending on the particular Nylon type. This makes it useful for a wide variety of manufacturing processes.
- Nylon is known for its flexibility, with the ability to return to its original shape after slight deformation.
- It is very durable and lasts for very long, making it cost-effective for manufacturers.
Chemical Properties
Owing to its strong bonds, nylon is not susceptible to breakdown when it interacts with most common chemicals. This includes such as alkali, weak acids, hydrocarbons, and oils. They can, however, be readily dyed, which increases their usefulness, especially in the textile industry.
Thermal Properties
Different nylon materials have a wide range of temperatures that can be tolerated. Some have relatively low melting points, making them desirable for creating complex designs, while those with high melting points are suitable for creating materials resistant to heat.
Some of these thermal properties include the following:
- Nylon has a melting point range of 220 to 330°C
- It has a nozzle temperature range of 230 to 310°C
- It has a mold temperature of up to 150°C
Fatigue Resistance
Time and time again, Nylon proves to be resistant to daily wear and tear seen in other manufacturing materials. It is well resistant to stress, heat, chemicals, radiation, etc. This makes it an excellent choice for manufacturers that need materials for long-term projects.
Noise damping
Noise damping refers to reducing the amount and intensity of noise a material produces. Nylon possesses the ability to convert noise and vibrations into heat, making it suitable for use in applications where we desire a serene environment.
Bearing and Wear Resistance
Most materials used in various industries deteriorate over time with exposure to constant stress. Nylon, however, is a strong manufacturing material with high tensile strength and good resistance to wear and tear.
Easy Machinability
Despite the strong and stiff nature of nylon, it is still an easy plastic block for milling using CNC nylon machining, making it a good choice for manufacturers producing readily available consumer goods.
Process of Nylon Machining
The nylon machining process entails cutting nylon into smaller and more desired blocks of plastic by a nylon machining machine. CNC nylon machining involves the following processes:
Step 1: Select the Right Cutting Tool
Selecting the appropriate cutting tool is important to get good results. There are several tools used in cutting, each with its special properties for cutting different materials.
The cutting tools used in machining steel are different from those used for nylon. Different nylon types also need different nylon machining tools because of their varying tensile strength. Some of the recommended cutting tools include single-end flute mills, two-flute end mills, etc., for fine precision.
Step 2: Set the Cutting Parameters
After selecting the right cutting tool appropriate for the nylon used, we set the correct cutting parameters. Different nylon grades for machining require different depths of cut. Generally, we recommend cutting parameters between 180 to 400 feet per minute and rates of between 12-20 mils/revolution.
Step 3: Fixturing
Fixturing the nylon means holding the nylon down in place for cutting to be smoothly carried out. A clamp is commonly used for this process, and this ensures stability during the cutting process for a smooth finish.
Step 4: Machining
Machining the nylon is the actual process of drilling nylon into smaller and more suitable parts. Here, the machinable plastic blocks are fixed with a clamp before machining nylon on a lathe, and milling it to smaller parts.
Step 5: Finishing
Nylon finishing involves everything we do after machining to enhance its properties. These finishing touches depend on the purpose intended for the nylon and include coating, softening, bleaching, dyeing, etc.
Benefits of Machined Nylon
Following thus far, we see that machined nylon offers several benefits, some of which include:
Low Weight-to-Strength Ratio
Plastic blocks produced from nylon CNC machining have a very low weight-to-strength ratio, also known as the specific strength. This shows how tough nylon is despite its weight, which is approximately ⅛ the weight of bronze. This property is especially beneficial in making light materials whilst maintaining durability.
Versatility
Through this article, we continually see how versatile CNC machined nylon is, from its use in the textile industry to its use in making electrical appliances and consumer products. This property makes CNC nylon machining lucrative for manufacturers and firms involved in nylon parts.
Cost Effectiveness
CNC nylon machining, especially cast nylon machining provides high performance with low production cost compared to other materials. It is also very durable, increasing its cost-effectiveness in the long run.
Limitations of Machined Nylon
CNC machined nylon offers a variety of benefits to several industries. However, there are still some limitations to the full use of machinable plastic blocks by nylon part manufacturers.
Moisture Absorption
All nylon can absorb moisture from the atmosphere and swell accordingly. This is its hygroscopic nature, and can readily cause nylon materials to deteriorate. Absorbed moisture also can affect the insulating properties of nylon, causing it to be unfit for its applications in electrical engineering.
Low Heat Resistance
Nylon has a relatively high melting point among the thermoplastics, but this, compared to other materials, is low, making it rarely used in operations where high temperatures are required, significantly limiting the applications of nylon.
Poor Dimensional Stability
Dimensional stability is the ability of a material to retain its dimensional structure in different environmental conditions. Because nylon readily absorbs moisture from the atmosphere, it is pliable to swelling and shrinking in different environments.
Fast Tool Wear
Tool Wear refers to the slow but gradual deterioration of the efficacy of a material over time. This process is faster in nylon parts that can be easily altered by normal environmental conditions compared to other manufacturing materials.
Nylon 6 and Nylon 66: Which is Better for CNC Machining?
Both nylon 6 and nylon 66 are some of the most popular nylon types manufacturers use for CNC machining. They, however, are different and are used in different applications.
Nylon 6 has a melting point of approximately 215°C, compared to nylon 66, with a melting point of 260°C, accounting for the flexibility seen in nylon 6, and nylon 66 being more thermally stable.
The structure of nylon 6 is less crystalline making, it more hygroscopic and prone to damage from chemicals and harsh UV radiation. Nylon 66, on the other hand, absorbs less moisture and is more resistant to chemicals and UV radiation.
Generally, nylon 6 is structurally stronger and finds its applications in textiles, electrical components, and materials with more flexibility. Nylon 66, on the other hand, is used in heavy-duty engineering materials requiring higher tensile strength. The choice of which nylon is better for CNC machining is dependent on what the product is intended for.
Applications of Machined Nylon
Aerospace
The aerospace industry is a major industry that relies on CNC machined nylon because of its mechanical properties and weight-to-strength ratio. This makes it an excellent option for aerospace industries in constant need of light, non-flammable, but durable materials that are cost and fuel-effective.
Automotive
Machined nylon finds heavy use in the automotive industry, especially because of its strong resistance to chemicals making it suitable for parts of vehicles in constant contact with chemicals. Its heat resistance also makes it ideal for its applications in the cooling system. Generally, it finds use in tires, cooling fans, headlights, and others.
Industrial
CNC machined nylon is relevant in a host of industries and industrial processes because of its durability, tensile strength, smooth finish, and resistance to chemicals.
Consumer Goods
A variety of common consumer goods are dependent on different types of nylon for their production. These include food packaging, clothing, bags, cooking utensils, toys for children and a lot more.
Electronics
Nylon is resistant to heat and electricity, making it suitable for use in the electronic industry as a coating material. It is resistant to magnetic charges and vibrations, some of the problems commonly seen in other materials.
Conclusion
Nylon machining is a versatile CNC application. It owes this to its impressive properties. However, with so many industries venturing into nylon machining, it is vital to trust only renowned manufacturers like HM for your materials and machining parts. Contact us today to get started.