Machined Plastic Parts: Design Considerations

When designing a part that will be produced by machining, careful consideration needs to be given to the application to ensure that all the performance requirements will be addressed in the part design. While machining is a forgiving process in that part designs can be easily changed, since the tooling costs required to produce a design are eliminated (as they are not with injection molding, for example), it still makes sense to get the part design right before production commences. In this blog we offer a checklist of considerations that should be taken into account as a part is designed.

Machined plastic parts: checklist of design considerations

The following checklist consists of categories of factors relating to application that should be reviewed when designing a plastic part that will be produced by machining. These factors are critical for ensuring that the part design and material selection are appropriate for the application conditions that will be encountered.

Category 1: Service conditions

  • Temperature, including maximum, minimum, continuous and cycling

  • Loading(including fatigue and cycle loading) that can affect compression and flexing

  • Exposure to environmental elements (such as outdoor use), including UV light

  • Exposure to chemicals and oils

  • Exposure to impacts

  • Exposure to abrasion and wear

  • Electrical properties, including conductivity or insulation

Category 2: Tolerancing

  • Dimensional shape retention required under load (deflection and compression) and temperature (thermo-sensitivity)

  • Tolerancing required in production

Category 3: Other considerations

  • Light conduction (transparent, translucent, opaque)

  • Texture

  • Colour

  • Regulatory requirements (i.e., FDA, UL, etc.)

Using this checklist together with material data sheets, it is possible to create a short-list of candidate materials that qualify as being suitable to meet the design considerations. Reputable suppliers of machined plastic parts will also be able to offer expert guidance that can help ensure that the optimal material is chosen to support the design considerations.

Machined plastic parts from CRG

CRG is a full-service provider of machined plastic parts to the industrial and automotive markets. We employ the latest CNC machining technology and all parts are produced in our ISO 9001-registered facility. Our experienced team uses a structured approach to reviewing each customer’s application, while providing the guidance needed to ensure that the right material is chosen for each job.

For over 30 years, CRG has been an industry leader in the conversion and fabrication of parts from flexible materials, including elastomers, foams and sponges, plastics and other materials. We offer industry-leading responsiveness and fast order turn-around, supporting our customers through all stages of the buying process.

If you are seeking machined plastic parts, CRG will be pleased to review and discuss your needs. To find out more about how we can support you, please contact our sales department at