Polycarbonate CNC Machining Service
Get an instant quote on custom polycarbonate machined parts with our online polycarbonate (PC) CNC machining service. Rapid prototyping and production of parts in a matter of days. Certified to ISO 9001:2015, ISO 13485 and AS9100D. Register with ITAR.
About CNC Polycarbonate Machining
Polycarbonate, referred to as PC, is an amorphous thermoplastic. This means that it tends to soften before melting, with no fixed melting point. It is supplied in black or transparent sheets and bars. Its clarity, shattering resistance and lower weight make it a preferred alternative to glass. It is better suited to high temperatures than acrylic. However, CNC machining of polycarbonate does not produce optically transparent parts and requires finishing.
Polycarbonate is an engineering plastic with excellent cracking toughness. Compared to other engineering plastics, it withstands impact while providing clarity, UV resistance and above-room temperature tolerance.
Generic PC (polycarbonate) at a Glance
| Application | Car headlight lenses, wheels, gaskets |
| Advantages | Moderate temperature resistance (up to 275℉ or 135℃), UV resistance, exceptional fracture toughness |
| Disadvantages | Scratches easily |
| Lead Time | Lead time is generally a minimum of 3 days. However, this can increase depending on availability or if the parts are to be internationally manufactured. |
| Price | $$ |
| Tolerances | Machining tolerances of 0.010” (0.25 mm) are achievable. |
| Wall Thickness | A minimum wall thickness of 0.03” (0.8 mm) is achievable. This can vary depending on the ratio of wall thickness to planar dimension. |
| Max Part Size | The maximum size of the part is determined by the machines available and the complexity of the part. |
Generic PC (Polycarbonate)
CNC machining of polycarbonate is quite common in this material. The material’s excellent impact resistance makes it an ideal choice for construction parts. The impact strength of polycarbonate is nearly twice that of ABS and has the highest impact strength of all common engineering plastics. It forms easily without breaking or twisting.
General PC Properties
| Tensile Strength, Yield (MPa) | Elongation at Break (%) | Hardness (Shore D) | Heat Deflection Temperature (°C) | Glass Transition Temperature (°C) |
|---|---|---|---|---|
| 40-154 | 3-233 | 90-95 | 57.2-208 | 142-152 |
Finishes
Only a limited range of surface treatments can be accepted, especially when CNC machining is easy to scratch.
Steam polishing: By exposing the surface to an atmosphere, the atmosphere causes parts of the surface to melt and flow. The process smooths the surface and fills any tool marks.
Sand blasting: Fine sand can be used to reduce visible tool marks.
Cost-saving Design Tips
Polycarbonate is a relatively expensive plastic. The following are more effective ways to reduce costs:
Sub-assembly: PC for processing is supplied in sheet or bar. Processing large pieces from a single piece of polycarbonate can be very expensive. Instead, individual components can be designed and then bolted together or bonded by plastic welding.
Standard dimensions: Order standard sheets or bars to avoid costly custom shapes.