Manufacturers use plastic machining in Chicago, IL, to produce durable, lightweight parts with properties such as chemical resistance, electrical insulation, and low friction. Plastic parts can replace metal in many functional roles when the application benefits from lower weight or reduced production costs.
At Roberson Machine Company, we machine plastic prototypes, replacement components, production quantities, and parts designed for use within larger assemblies and equipment.
Learn More About
- What plastic machining does for parts produced from solid stock
- How heat, workholding, and material behavior shape the machining plan
- Which CNC processes create different plastic parts and features in Chicago, IL
- Where machined plastic components are used across industrial operations
- How common plastics compare by material properties and applications
- How process planning supports higher quantities and repeat orders
- Practical answers about pricing, materials, and production decisions
For help planning a plastic machining project in Chicago, IL, contact us online or call 573-646-3996 to discuss your material requirements, expected quantities, and target schedule.
How Manufacturers Machine Plastic Parts
Plastic machining uses a subtractive manufacturing process to create finished components by removing material from solid plastic stock. Based on a drawing or digital model, CNC equipment follows programmed cutting paths until the component reaches its required shape and dimensions.
Stock forms used for machined plastic parts include sheets, plates, blocks, rods, and tubes. Using stock material removes the need for a dedicated mold, making it possible to produce or update components without new tooling.
Plastic Machining vs. Metal Machining
Plastic can be machined with many of the same CNC processes used for metal components. The main difference is how the material responds to heat, cutting pressure, workholding, and changing environmental conditions.
Heat and Cutting Quality
Plastic materials typically conduct heat less efficiently than metals, making temperature control around the cutting area especially important. Excessive heat can soften, melt, burn, or distort the material.
How chips leave the cutting area can affect the resulting edge and surface. Chips left near the tool may retain heat or interfere with the cutting path, contributing to burrs, fuzzy edges, cracks, and other surface defects.
Workholding Without Part Distortion
Plastic stock needs secure support without clamping pressure that compresses, marks, or distorts it. Factors affecting workholding and dimensional control include:
- Flexing in thin walls or features without adequate support
- Bowing in large parts or materials with limited stiffness
- The effects of temperature, moisture absorption, and internal stress on final dimensions
Planning for Different Plastic Materials
Acrylic, nylon, acetal, PEEK, PTFE, UHMW, and similar materials each have distinct machining characteristics. Both the material specification and the part’s operating conditions influence how the component should be machined and inspected.
How Are Plastic Parts CNC Machined in Chicago, IL?
The appropriate precision CNC machining process or combination of processes depends on the plastic stock form, part geometry, tolerances, and required features.
| CNC Process | Example Plastic Parts | How the Process Is Used |
|---|---|---|
| CNC Milling | Housings, covers, brackets, plates, mounts, manifolds, fixtures, and acrylic instrument parts |
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| CNC Turning | Bushings, sleeves, spacers, rings, pulleys, shafts, pins, and ink rollers |
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| 5-Axis Machining | Contoured housings, complex fixtures, medical components, and multi-sided parts |
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| Multi-Axis Machining | Valve components, sensor hardware, enclosures, tooling components, and parts with features on multiple sides |
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Which Sectors Use Plastic Machining in Chicago, IL?
Plastic components produced through Roberson Machine Company’s industrial machining capabilities support equipment, tooling, products, and larger assemblies in a range of sectors.
- Aerospace: When the application supports a material substitution, machined plastic parts can replace metal components to reduce the weight of fixtures, instrument hardware, insulating components, and similar parts.
- Medical: Clear, electrically insulating, and chemical-resistant materials support plastic medical components for diagnostic equipment, specialized fixtures, and frequently cleaned applications.
- Automotive and EV: Within vehicles, testing systems, and production equipment, plastic parts can isolate electrical components, resist fluids, and reduce friction between moving surfaces.
- Packaging: Guides, changeover tooling, and material-handling components benefit from plastics that resist wear, moisture, and frequent cleaning.
- Automation and Robotics: Machined plastic tooling can reduce the mass carried by automated equipment. Plastic guides and wear surfaces also support smooth movement while protecting handled products.
- Oil and Energy: Oil and energy equipment uses machined plastics where corrosion resistance, chemical compatibility, or electrical insulation affects material performance.
The component’s mechanical loads, motion, temperature range, chemical contact, electrical requirements, and operating environment guide material selection.
What Types of Plastic Can Be CNC Machined?
Many thermoplastics and engineering plastics can be machined from sheet, plate, block, rod, or tube stock. Application requirements determine the best plastics for CNC machining, with several material families used regularly for industrial components.
Acetal and Nylon
Acetal combines low friction and wear resistance with limited moisture absorption, supporting parts that need dimensional stability.
Nylon combines durable, abrasion-resistant performance with greater moisture absorption that can affect dimensional stability.
Acrylic and Polycarbonate Materials
Acrylic materials (like plexiglass) combine optical clarity and surface hardness for instruments, windows, covers, and displays. Polycarbonate offers a transparent but more impact-resistant option for guards, housings, and parts that encounter frequent handling.
PTFE and UHMW
These plastics support different applications that benefit from low-friction material performance:
PEEK and High-Performance Plastics
PEEK combines chemical resistance with useful mechanical performance at demanding temperatures.
PEEK generally suits applications where its performance advantages justify a higher material cost than standard engineering plastics.
Plastic machining may also use ABS, polypropylene, polyethylene, PVC, and similar materials selected for the application. How the plastic machines and performs after production depends partly on its grade, additives, reinforcement, and stock condition.
Scaling Plastic Machining for Production Volumes
High-volume plastic machining in Chicago, IL, produces larger part quantities and repeat orders from plastic stock through controlled CNC processes. As a project moves through production ramp-up, the process must carry the approved materials, setups, dimensions, and finish quality into increasingly larger production releases.
Larger releases and repeat orders may require planning for:
- Material supply: Confirming that each production release uses the specified resin, grade, and stock form with the required material records.
- Documented setups: Creating repeatable setup documentation for fixtures, tools, machine settings, and part orientation.
- Tool-life planning: Replacing tools at planned intervals before wear creates dimensional changes or finish defects.
- Production inspection: Developing an inspection plan that covers initial parts, production checks, and completed components.
- Revision control: Connecting the correct drawings, programs, inspection records, and approved revisions to each production release.
These controls support consistency and precision in mass-production CNC machining and create a documented process that can be applied when the customer places another order.
FAQs About Chicago, IL, Plastic Machining
Should a plastic component be machined or molded?
CNC machining often makes more sense for components that require frequent design changes, prototype quantities, or features that are not practical to mold. Manufacturers can produce the part without first investing time and money in mold design, manufacturing, and testing.
Molding may provide better economics after the design stabilizes and production quantities become large enough to recover the tooling cost. Higher-volume parts may still require CNC machining because of their geometry, material, tolerances, or required secondary features.
What details are needed for a plastic machining quote in Chicago, IL?
Quoting begins most clearly with a drawing or digital model of the plastic component. Supporting information may include:
- Overall part size and specified features
- Critical dimensions and permitted variation
- Specified resin and material grade
- Initial order size and expected recurring quantities
- Finish requirements and acceptable edge condition
- Required threads, inserts, and mating components
- Inspection and documentation needs
- Requested delivery schedule
If material selection is part of the project, describe the component’s function, environment, and exposure to chemicals, moisture, electricity, temperature, or mechanical loads.
What determines the cost of a machined plastic part in Chicago, IL?
The cost of plastic machining reflects the selected material, stock dimensions, quantity, setup requirements, machining time, and inspection plan. Material price can increase significantly when the application requires PEEK or another high-performance plastic.
Machining a basic component from readily available stock generally costs less than producing a complex part with demanding dimensions, multiple operations, or difficult workholding.
What affects achievable tolerances in plastic machining?
The appropriate tolerance range reflects the plastic material, overall size, wall thickness, stock stability, and service environment. Machining and inspection results can be affected by temperature changes, moisture, internal material stress, and the pressure used to hold the part.
Specified tolerances should reflect how the component functions rather than expectations carried over from metal parts. Features affecting assembly, movement, alignment, sealing, or component fit should be identified as critical on the drawing.
How do I choose a plastic for CNC machining?
No one plastic provides the best option for every CNC machining project. The appropriate choice generally meets the component’s functional requirements without introducing unnecessary performance or material cost.
Stable, low-friction applications frequently use acetal as a practical material option. For tough, wear-resistant parts, nylon may offer the more appropriate properties. Acrylic and polycarbonate provide options for clear components. PTFE, UHMW, and PEEK support more specialized operating requirements. Resin formulation, grade, and additives can affect the finished component’s properties.
Can machined plastic parts replace metal components in Chicago, IL?
Applications that need less weight, electrical insulation, reduced friction, or chemical and corrosion resistance may benefit from replacing metal with plastic. The existing metal design may need to change before it can perform effectively in plastic.
The replacement design should account for:
- Mechanical loading and impact conditions
- Service temperatures and chemical contact
- Wear, friction, and expected service life
- Dimensional changes from heat or moisture
- Required wall thickness, fastening methods, and support
Addressing these factors may require changes to the component design before it is machined from plastic.
Request Plastic Machining Support in Chicago, IL
Roberson Machine Company supports plastic machining projects based on supplied drawings, models, and specifications, from prototypes and replacement parts to planned production.
- The selected plastic and intended use guide production planning, including how the chosen resin and stock interact with the component’s critical features and operating environment.
- Complex plastic parts may require several CNC operations when the design combines milled, turned, drilled, threaded, or multi-sided geometry.
- New parts can move from prototype machining into recurring production through documented production methods that support consistent future releases.
Send Roberson Machine Company your part drawing or model along with the material, quantity, and requested schedule. To discuss your plastic machining project in Chicago, IL, contact Roberson Machine Company online or call 573-646-3996.