Plastic CNC Machining
Engineering plastics offer lightweight, corrosion-proof alternatives to metal — ideal for medical, aerospace, chemical processing, and food-grade applications where metal cannot be used.
Alloy Grades & Properties
| Grade | Properties | Applications |
|---|---|---|
| PEEK | High strength, chemical resistant, biocompatible, up to 250°C | Medical implants, aerospace, chemical processing |
| Delrin (POM) | Low friction, excellent machinability, good stiffness | Gears, bushings, fixtures, consumer products |
| Nylon 6/6 | Tough, wear-resistant, self-lubricating | Bearings, rollers, structural insulators |
| PTFE (Teflon) | Lowest friction, chemical inert, non-stick | Seals, gaskets, chemical handling, bearings |
| Ultem (PEI) | High strength, flame retardant, autoclavable | Medical devices, aerospace interiors, electrical |
Machining Tolerances
Standard ±0.1mm · Precision ±0.05mm · Note: plastics are temperature-sensitive — specify operating environment
Surface Finishing Options
- As-machined
- Vapor polishing (PC, acrylic)
- Tumbling & deburring
- Thread inserts (Helicoil)
- Laser marking
Common Applications
- Medical device components (non-implant)
- Chemical processing fittings
- Aerospace interior and insulation parts
- Food processing equipment
- Electrical insulators and housings
DFM & Machining Tips
- Plastics require sharp tools and moderate speeds — heat causes melting and dimensional drift
- PEEK and Ultem need annealing before machining to relieve internal stress
- Design generous internal radii — plastics are brittle under sharp corners
- Allow for thermal expansion in tight-tolerance assemblies
Frequently Asked Questions
PEEK vs metal — when to choose PEEK?
PEEK when you need chemical resistance, biocompatibility, or weight savings without corrosion concerns. Metal when you need maximum stiffness, heat tolerance above 250°C, or tightest tolerances.
Can you machine clear acrylic and polycarbonate?
Yes — CNC milling and turning for acrylic (PMMA) and polycarbonate. Vapor polishing available for optical clarity on acrylic parts.
Are plastic parts suitable for autoclave sterilization?
Ultem (PEI) and PEEK withstand repeated autoclave cycles. Specify sterilization requirements in your RFQ for material recommendation.
Need Parts in Plastic?
Upload your design for a free quote and DFM feedback within 24 hours. Our engineers will recommend the optimal grade and finishing.
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