Make the functional intent easy to manufacture.
CNC cost is driven by setups, cycle time, tooling, material removal and inspection. The best designs give cutters physical access, avoid unnecessary depth and apply tight tolerances only where assembly or performance requires them.
- 01Use generous internal corner radii
- 01Avoid deep, narrow pockets and slots
- 01Keep walls thick enough to resist cutting forces
- 01Align critical features to common setup directions
Tight tolerances create a chain of consequences.
A tighter number can require slower passes, more stable fixturing, controlled temperature and additional inspection. Define datum structure and fits from actual functional relationships instead of applying blanket title-block tolerances.
- 02Dimension from functional datums
- 02Specify surface roughness only where needed
- 02Use standard hole and thread sizes
- 02State inspection expectations for critical features
Design with real cutters and setups in mind.
Most internal features are created by rotating tools, so perfectly sharp internal corners are not possible. Deeper features require longer, more flexible tools and usually larger radii to maintain rigidity.
- 03Prefer pocket depth below four times tool diameter
- 03Relieve unavoidable square internal corners
- 03Provide tool clearance around angled features
- 03Split inaccessible geometry only when assembly permits
Bring us the hard part.
Share your CAD and requirements. An engineer will respond with the clearest path forward.
Start a project ↗What engineers ask.
What is a good internal corner radius?+
Use the largest radius the design allows. A radius slightly larger than the cutter radius reduces engagement and improves finish; pocket radii of roughly one third of pocket depth are a useful early guideline.
What is a standard CNC tolerance?+
General tolerances often follow ISO 2768-m or a supplier standard, but drawing requirements control. Feature-specific tolerances should come from functional fits and inspection capability.