A plain bearing that runs unattended for years in a ship’s propulsion system without corroding. Or a precision ring that endures thousands of cycles in a filling machine. These types of parts are created on a CNC machine, starting from a block of plastic from which various chips are removed. That is the essence of machining.
Turning and milling form the basis of plastic machining. In turning, the raw material rotates while the tool removes material. Milling works the other way around: here, the tool itself rotates and moves over or through the workpiece. But a finished part almost always requires more than just one of these steps. Often, drilling and tapping are also required; sometimes inserts are installed; and in many cases, deburring is necessary to remove sharp edges.
Without these finishing operations, you have a semi-finished product; not a final product that you can install. That is why we at ANKRO also offer assembly and finishing services. As a result, a part can be fully finished and ready for installation when shipped to customers.
The difference between a good and an excellent part lies not only in the finishing operations, but above all in how you handle the material.
Machining plastics is a specialized field. It starts with the basic properties of the material. Some plastics are softer and more elastic than metal, causing them to react differently to tools and equipment. However, with precise settings, this results in cleaner cuts and less post-processing than with metal. That said, the cutting edges and milling heads must be specifically tailored to plastic, and the way they move through the material is programmed differently than what you’re used to with steel, for example.
Heat plays an important role in this process. Metal dissipates the heat generated by machining quickly, while plastic retains that heat longer. That is precisely what makes precise process control so important: the right cooling, speed, and sufficient space for the material together determine whether a part falls within specifications. You build such expertise by producing thousands of plastic series on the machine.
That process knowledge also determines which material you use in the first place. Because the differences between plastics are at least as great as the difference between plastics and metal.
POM is the “workhorse” for parts where low friction and dimensional stability are key. It is often used to make gears and plain bearings. PA6, better known as nylon, is impact-resistant and wear-resistant, making it a logical choice for parts in mechanical engineering. PETP retains its shape exceptionally well and is used where rigidity is essential. Think of precision parts in the analytical sector.
For more demanding conditions, other materials are the obvious choice. PTFE, which most people know as Teflon, is virtually chemically resistant. In the petrochemical and pharmaceutical industries, that is a property you cannot do without. PE is widely used in the food industry due to its excellent food safety properties.
What works well with POM may not work at all with PTFE. Each type of material reacts differently to the tools, heat, and stress in the workpiece. That knowledge of materials is what makes plastic machining a specialized field. It also explains why so many industries deliberately choose plastic: when the right material is used in the right place, these parts can perform better than their metal counterparts.
Plastic components are significantly lighter than their steel counterparts. In shipbuilding and medical technology, this makes a direct difference in energy consumption and day-to-day handling. In addition, plastic does not corrode, even after years of exposure to saltwater or chemically aggressive environments. Metal bearings require regular lubrication, whereas plastic variants operate maintenance-free. In the analytical industry, the electrical insulating properties of plastic also play a significant role.
The combination of low wear and chemical resistance ensures that parts last longer and need to be replaced less often. Viewed over the entire service life, this can result in lower costs compared to metal.
Plastics are not necessarily cheaper to purchase. High-performance engineering plastics such as PVDF cost more per kilogram than standard steel. Tolerances work differently because plastic is more sensitive to temperature and moisture. And you can’t simply copy a steel design to plastic without adjusting the geometry. But those who design with the right expertise from the start can achieve performance levels with plastic that are difficult to match with metal.
Plastic parts are lighter, corrosion-resistant, and often low-maintenance. They are electrically insulating and chemically resistant.
The most commonly used plastics are POM, PA6, PETP, PE, PTFE, PVDF, and PP. Each plastic has unique properties suited to specific applications. POM for low friction and dimensional stability, PA6 for impact resistance, PTFE for chemical resistance, and PE for food safety.
Plastics react differently to tools and heat than metals. This requires specific tools and machines, adjusted cutting parameters, and detailed process control for each type of plastic. The combination of material and years of experience at the machine makes the difference between a rejected part and a product that falls exactly within specifications.
There is a fundamental difference between a machining company that also works with plastics and a company that specializes exclusively in plastics. At ANKRO, plastics are by no means a side business. Our machinery has been designed from the ground up for high-volume plastic production, ranging from ten pieces to runs of 100,000 or more. Our team works with these materials every day and understands how each plastic behaves in practice.
Are you in the middle of choosing a material, or are you considering switching from metal to plastic? We’d be happy to help you figure it out.
When moving from prototype to mass production, the choice of material suddenly takes on a whole new level of importance. A material that performs well in a single part may fall short in terms of consistency, cost, or machinability when produced in quantities of a thousand. Choosing the right plastic for mass production therefore hinges on three questions: What is technically suitable? What is economically scalable? And what remains consistent across batches?
Large series often start small, and this also applies to complex series work. ANKRO has over 25 years of experience in the process of upscaling, facilitated by craftsmanship and modern, automated machinery. Curious about how we organize the process from prototyping to series production while maintaining quality? In this customer case study, we demonstrate that even complex parts with precise finishes are suitable for series production.
At ANKRO Kunststof Verspaning, we combine innovation, craftsmanship, and chain collaboration to realize sustainable and circular solutions. We have extensive experience in machining recycled plastic and already successfully supply these materials to various customers in practice.
Please feel free to contact us. You can do so by phone at +31 (0)183 304 872 or by filling out the contact form. We will handle your question as soon as possible.
