Using plastics in CNC machining is highly relevant for low-volume production, things with close tolerance dimensions, and objects with complex mold structures. Machining plastic is an effective manufacturing method. Many different polymers are available for CNC machining. While some are designed for lower cost and lower performance, others are highly engineered and have remarkable performance.
When should you choose plastic for CNC machining?
Plastic is a good choice for CNC machining when a project calls for a cheap, corrosion-resistant, lightweight material. Plastic can also be used for components that need to be flexible or chemically resistant.
Factors to Consider When Choosing a Plastic
The machinability of a material is influenced by its physical characteristics. As a result, the outcomes you can get from your workpiece will differ depending on the material. With polymers, your workpiece’s size and shape may vary during or even after machining. As a result, design engineers must consider material qualities to guarantee that their design can be manufactured.
Thermal Expansion and Heat Deflection Temperature (HDT)
At high temperatures, almost every material expands and gains volume. The tooling used in CNC machining generates heat when it comes into contact with the material. In comparison to metals, plastics have a higher coefficient of thermal expansion. As a result, they may experience a larger size change due to machining.
Strength and Hardness
You can consider a plastic’s strength and hardness characteristics to ensure it can withstand the demands of its intended application.
Moisture Absorption and Chemical Reaction
Certain plastics are susceptible to chemical damage and can absorb moisture from the air, coolant, or other sources. It might even be necessary to store them in air-conditioned spaces or sealed bags.
Light Transmittance, Transparency, and Appearance
Design elements like appearance and related characteristics like light transmittance may be crucial. If so, you have fewer options for plastic materials to choose from.
Top Plastics Used in CNC Machining
ABS is a fantastic material for CNC machining. ABS is a durable, impact-proof plastic that is also immune to chemicals and electrical currents. Since ABS is simple to color, the finished product looks beautiful. It’s the most popular material we use for quick prototyping because of its adaptability and durability.
ABS and nylon both have a number of favorable traits. Because of its higher tensile strength, we utilize it for fabric and rope. To improve the desirable qualities of nylon and ABS resins, glass fibers are frequently added to the mixture.
PMMA is a strong, transparent resin that can be used in place of glass or to create other clear optical components. Although less impact-resistant than polycarbonate, it is scratch-resistant. PMMA has the benefit of not containing bisphenol-A, making it suitable for food storage.
PEEK is a real engineering plastic with great strength and stability. It can resist extended exposure to high temperatures and can be utilized as a metal substitute in various applications.
Ultra-high molecular weight polyethylene is referred to as UHMWPE. In reality, PE comes in various forms with various mechanical and chemical characteristics. UHMWPE is particularly tough and durable, has a high level of chemical resistance, and has a slippery surface.
What Are Typical Uses For CNC Plastic Parts?
There is a wide variety of plastic polymers, each with its own characteristics and applications. Here are a few common applications for CNC plastic parts:
- Production of implants and medical devices.
- Use in the production of plastic components for the food and beverage sectors.
- Making insulating components for electrical devices
- Making components for vehicles and aircraft
- Making lenses
As you may have guessed, numerous plastics can be machined using CNC. However, which plastic is ideal for your project depends on your objectives for the role. And if you need help choosing the proper material for your application, experts at karkhana.io can offer guidance to ensure the success of your project.
If you are interested in utilizing the expertise of our partners for the CNC production requirements you have, the first step is to create an account on our digital platform.