Machined plastic prototypes for fit and design checks
A CNC-machined plastic prototype is useful when a project needs a part made to a defined geometry for review. It may be used to check assembly, clearances, interfaces or a design feature. Whether it is suitable for a functional test depends on the resin grade and the test conditions.
This page is about machined prototype parts. The broader plastic rapid prototyping page discusses how to define a prototypeâs purpose; the rapid prototyping capability page outlines the service scope.
State what the prototype needs to prove
- For a fit check, identify mating surfaces, hole locations and assembly interfaces.
- For a visual review, specify color, texture or visible surfaces if they are requirements.
- For a functional evaluation, state the intended load, temperature, chemical exposure or other test condition.
- Identify whether the prototype must use the intended production resin or a named substitute.
Different plastics and grades can have different properties. A substitute may help check geometry but should not be treated as equivalent for performance without approval. Thin walls, deep pockets and small radii should be identified on the drawing so machinability can be reviewed.
Send a complete prototype request
Include the CAD model, drawing revision, resin designation, quantity, critical dimensions, finish and delivery destination. Mark the features that must be accepted and distinguish them from reference dimensions. This helps keep the quotation aligned with the purpose of the prototype.