Common engineering plastics
| Material | Properties | Typical applications |
|---|---|---|
| PEEK | High temperature, chemical-resistant, biocompatible | Medical, aerospace, electronics |
| Delrin (Acetal) | Low friction, high stiffness, dimensional stability | Gears, bearings, wear parts |
| Nylon | Tough, wear-resistant, impact-resistant | Gears, structural components |
| PTFE (Teflon) | Non-stick, chemical-resistant, high temperature | Seals, bushings, liners |
| ABS | Tough, impact-resistant, cost-effective | Enclosures, housings, prototypes |
PEEK is one of the most challenging plastics to machine due to its high melting temperature and abrasive properties.
Plastic machining challenges
- Heat sensitivity — plastics melt or deform at high temperatures
- Burr formation — plastics tend to form burrs during cutting
- Dimensional instability — plastics may warp during machining
- Tool wear — abrasive plastics (PEEK) wear tools faster
- Chip control — plastic chips can be stringy and difficult to manage
Choose a supplier with experience in plastic machining. Plastic machining requires specific tooling and techniques that not all shops have.
Best practices for plastic machining
- Use sharp tools — sharp edges reduce heat and burr formation
- Maintain consistent feeds — avoid dwell and overheating
- Use coolant — reduces heat and improves surface finish
- Minimize clamping force — prevents deformation of plastic parts
- Consider stress relieving — for critical dimensions, stress relief may be needed
Using metal machining feeds and speeds for plastics. Plastic requires higher speeds and lower feed rates to avoid melting.
Typical applications
- PEEK — medical implants, aerospace components, electronics insulation
- Delrin — gears, bearings, automotive components
- Nylon — structural components, wear parts, rollers
- PTFE — seals, bushings, chemical-resistant components
- ABS — enclosures, housings, prototypes
Frequently Asked Questions
What is the easiest plastic to machine?
Delrin (Acetal) is one of the easiest plastics to machine due to its excellent machinability and dimensional stability.
Which plastic is the most challenging to machine?
PEEK is challenging due to its high melting temperature, abrasiveness, and tendency to work-harden.
What tolerance can plastic machining achieve?
Typical tolerance for plastic machining is ±0.01mm to ±0.05mm, depending on the material and geometry.
Do plastics require special tooling?
Yes. Sharp tools with specific geometries are recommended for plastic machining to reduce heat and burr formation.