Custom Multi-Spindle Gun Drilling Scales Small Component Production

Customer Background

The customer manufactures small precision components for automotive and industrial systems — metering pins, distributor shafts, and ABS sensor probes — each requiring a small-diameter deep hole drilled along its length. The parts are simple in geometry but produced in large batches, so the economics of the job depend almost entirely on how many parts the drilling machine can run in parallel.

The Challenge

Small-component deep hole drilling is a simple operation with very specific failure points:

One hole per part, thousands per batch. Each component needs a single small-diameter deep hole. Because the geometry is simple, per-part cost is dominated by throughput — how many parts the machine can drill simultaneously.

Deep small-diameter holes. Ø3–16mm holes to 1,000mm represent depth-to-diameter ratios from 62:1 to over 300:1. Chip evacuation and straightness are the limiting factors, and a feed interruption at these ratios snaps the drill.

Parallel drilling needs consistent pressure. When several spindles drill at once, oil pressure must be correct for every spindle and every tool diameter. Manually setting and maintaining pressure across parallel spindles is impractical and error-prone.

Odd-shaped, small workpieces. These parts do not sit on clean reference surfaces. Workholding must be matched to each component, and alignment must survive the loading cycle.

Floor space is a cost. Scaling throughput by adding single-spindle machines multiplies floor space, operators, and loading time. The customer needed more parts per shift per square meter, not more machines.

The Solution

RuidCNC supplied a Multi Spindles Gun Drilling Machine — a custom-configured multi-spindle machine sized to the customer’s product mix:

• Custom spindle count — the number of spindles is specified at order, matched to the customer’s batch volume and component family
• Ø3–16mm drilling range to 1,000mm — covers the small-diameter deep holes across the product line
• 4 parallel spindles at 6,000 rpm — four parts drilled simultaneously per machine
• 15 kW servo high-pressure oil pump with self volume adjustment — pressure is set and maintained automatically across all spindles, removing manual setup between diameters
• Custom workholding — fixtures matched to small, odd-shaped components
• Compact footprint — N× throughput without N× floor space

Key Machine Specifications

Parameter	Specification
Drilling range	Ø3 – Ø16 mm
Max drilling depth	1,000 mm
Spindle max speed	6,000 rpm
High-pressure oil pump	15 kW servo, self volume adjustment
Configuration	Custom spindle count

Results

Metric	Previous Single-Spindle Process	Custom Multi-Spindle (4)	Improvement
Parts per shift	240	880	3.7× throughput
Spindle count	1	4	4× parallelism
Setup time between diameters	25 minutes	~5 minutes (auto pressure)	80% reduction
Scrap rate	2.4%	0.5%	79% reduction
Hole straightness (Ø10mm × 800mm)	0.12 mm/m	0.05 mm/m	58% better
Floor space per part	1 unit	0.25 unit	4× density

Process Validation

The process was validated through:

• Hole position and straightness measurement on sample parts from each spindle
• Throughput study across a full production shift
• Oil pressure consistency check across all parallel spindles
• Scrap-rate analysis across a full production batch

Conclusion

The Multi Spindles Gun Drilling Machine applies parallel drilling economics to small precision components. With a spindle count custom-specified to the customer’s volume, four parts drilled simultaneously, and a self-adjusting servo oil pump that keeps pressure consistent across spindles, the machine increased parts per shift by 3.7× while cutting setup between diameters by 80%. For small-component manufacturers whose per-part cost is dominated by throughput, the custom multi-spindle machine delivers more parts per shift and per square meter than adding single-spindle machines ever could.

Figures are representative of typical applications.