Small-diameter deep-hole precision components require stable machines, controlled heat input, accurate boring or drilling strategies, and strict inspection for straightness, surface finish and concentricity.
Quick Answer
These components are difficult because a long, narrow bore or internal feature can amplify tool deflection, heat buildup, chip evacuation problems and measurement error. A successful process depends on rigid equipment, suitable tooling, controlled coolant strategy and careful inspection planning.
Common Materials
- 300M steel
- 4340 steel
- 17-4 PH stainless steel
- Inconel 718
- 7075 aluminum
Manufacturing Considerations
- Straightness: Long bores require datum control and verified alignment.
- Surface finish: Functional bores often need controlled Ra values and clean edges.
- Heat control: Excessive heat can damage surface integrity and reduce repeatability.
- Chip evacuation: Deep features require reliable chip removal to avoid scoring.
- Inspection: Bore gauges, CMM, air gauges or optical inspection may be required depending on part geometry.
HYR-CNC Recommendation
For this type of work, HYR-CNC recommends evaluating turning centers, boring solutions, 5-axis machining centers and dedicated inspection fixtures based on part length, bore diameter, material and production volume.