Small Deep Hole Drilling for Precision Instrument Components

Customer Background

The customer manufactures precision instrument components — servo valve sleeves, nozzle bodies, and sensor housings — where small-diameter deep holes define the part’s function. A metering orifice or a pilot passage drilled off-center by a few microns changes flow characteristics and can send a calibrated component to scrap.

The Challenge

Small precision components fail on a different axis than large production parts — not on throughput, but on repeatability and flexibility:

Tolerances in the micron range. Depth and position of Ø1.5–8mm holes must repeat well under ±0.01mm. On a conventional deep hole machine sized for larger work, holding this repeatability across a small component is not guaranteed.

High-mix, small-batch production. Precision instrument runs are short and change frequently — a batch of servo sleeves, then sensor housings, then a prototype run. The machine must switch part types and materials quickly, or changeover time erases any cycle-time gain.

Fragile small drills. At Ø1.5–3mm, the gun drill is slender and the entry point is unforgiving. Feed variation or entry wander at the start of the hole scraps parts and snaps drills.

Materials that vary part to part. Components arrive in stainless, hardened alloys, brass, and engineering plastics. One machine must drill all of them with predictable parameters, without long reconfiguration.

Prototype-to-production continuity. The same part is often developed as a prototype, then moved to production. If the prototype and production machines differ, the process developed in R&D does not transfer.

The Solution

RuidCNC supplied a Small Deep Hole Drilling Machine — a compact, high-precision machine built around small-diameter drilling:

• Ø1.5–20mm drilling, 300mm depth — covers the small precision components this customer produces
• ±0.005mm repeatability — CNC depth and positioning control that holds micron-level consistency across batches
• 10,000 rpm spindle with BT40/BT50 taper — speeds matched to small-diameter drills, with flexible tooling options
• 10 m/min rapid traverse — fast positioning and quick changeover between part types
• 1,000 kg table capacity — rigid workholding even for small, lightly-clamped fixtures
• 60 L/min coolant with 300 L tank — reliable chip evacuation in small-diameter deep holes
• Compact footprint — fits a laboratory, R&D cell, or production line without crowding

Key Machine Specifications

Parameter	Specification
Drilling diameter	Ø1.5 – Ø20 mm
Max drilling depth	300 mm
Repeatability accuracy	±0.005 mm
Spindle max speed	10,000 rpm
Spindle taper	BT40 / BT50
Rapid feed speed	10 m/min
Coolant flow	60 L/min
Table bearing capacity	1,000 kg

Results

Metric	Conventional Deep Hole Machine	Small Deep Hole Machine	Improvement
Depth repeatability	±0.05 mm	±0.005 mm	10× better
Position repeatability	±0.03 mm	±0.008 mm	73% better
Batch changeover time	40 minutes	12 minutes	70% reduction
Cycle time per part (Ø3mm × 200mm)	9 minutes	5.5 minutes	39% reduction
Scrap from drill entry wander	3.5%	0.8%	77% reduction
Prototype-to-production setup	Re-fixture	Same setup	Eliminated

Process Validation

The process was validated through:

• Hole position and depth measurement on a CMM across consecutive batches
• Repeatability study over 200 consecutively drilled parts
• Entry-quality and surface finish inspection on sample holes
• Dimensional comparison of prototype and production parts from the same setup

Conclusion

The Small Deep Hole Drilling Machine is built for the problem that large machines ignore: drilling small diameters, to micron-level repeatability, across frequently changing batches. With ±0.005mm repeatability, fast 10 m/min positioning, and a compact footprint that suits R&D and production alike, the customer improved depth repeatability by an order of magnitude, cut batch changeover by 70%, and carried the same setup from prototype to production. For precision instrument makers, it is the difference between a calibrated result and a scrapped batch.

Figures are representative of typical applications.