Star Micronics SC-20

$500,000 – $900,000 Updated 2026-03-17

Key Specifications

machine type

CNC Multi-Spindle Automatic Lathe

number of spindles

number of stations

bar capacity

1 – 20 mm (0.04 – 0.79 in) diameter

spindle speed

Independent per spindle, up to 8,000 RPM

spindle drive

Individual CNC servo motors per spindle

Overview

The Star Micronics SC-20 is a CNC multi-spindle automatic lathe designed to deliver high-volume production of small precision turned parts at diameters up to 20 mm. Star Micronics, globally recognized for its Swiss-type CNC lathes, developed the SC-20 as a fully CNC multi-spindle alternative to cam-driven systems, bringing the programming flexibility and fast changeover of CNC to the multi-spindle platform. Where conventional multi-spindle automatics require cam sets and lengthy mechanical setup, the SC-20 programs entirely through CNC, making it practical for production runs where part families change weekly rather than monthly.

The SC-20 features six spindles arranged in a drum configuration, with each spindle capable of independent speed and direction control. This per-spindle CNC flexibility allows the machine to run different spindle speeds at different stations — optimizing cutting speed for each operation rather than running all spindles at the same speed as traditional cam-driven machines. Each station accommodates a mix of turning, drilling, boring, threading, and cross-drilling tools through CNC-controlled tool slides, with the ability to use back-working units for simultaneous front and rear machining to complete parts in cycle without secondary operations.

Star's control system supports FANUC-compatible programming, providing a familiar interface for shops already running Star Swiss-type lathes or other Fanuc-controlled equipment. The machine handles bar stock from 1 mm to 20 mm in diameter, covering the small-diameter precision parts segment dominated by medical device components, electronic hardware, and miniature hydraulic fittings. Cycle times for typical small parts run 3–10 seconds per piece, providing throughput competitive with cam-driven systems while maintaining the changeover speed of CNC.

At $500,000–$900,000, the SC-20 occupies a competitive price point relative to both cam-driven multi-spindles and the higher-end fully-CNC systems from Index and Tornos. Its appeal lies particularly in shops that make the transition from single-spindle Swiss turning to multi-spindle production, where Fanuc-compatible programming reduces the learning curve and shops can leverage existing programmer expertise on the new platform.

Full Specifications

Parameter	Value
Machine Type	CNC Multi-Spindle Automatic Lathe
Number Of Spindles	6
Number Of Stations	6
Bar Capacity	1 – 20 mm (0.04 – 0.79 in) diameter
Spindle Speed	Independent per spindle, up to 8,000 RPM
Spindle Drive	Individual CNC servo motors per spindle
Actuation	Full CNC (no cams)
Back Working Spindles	2 back-working units standard
Tool Slides Per Station	2–3 CNC slides per station (configurable)
Coolant	Through-spindle coolant standard
Bar Feeder	Automatic magazine bar feeder
CNC Control	Fanuc-compatible CNC
Programming	Fanuc-compatible G-code
Materials	Steel, brass, aluminum, titanium, plastics
Machine Weight	Approx. 7,500 kg (16,535 lb)
Typical Cycle Time	3 – 10 seconds per part (part-dependent)

Strengths & Limitations

Strengths

Fully CNC actuation with no cams means part changeover is a program change rather than a cam replacement — enabling practical multi-spindle production on weekly-changing part families
Independent CNC spindle speed per station allows speed optimization at each position, improving tool life and cut quality compared to fixed-speed cam-driven systems
Fanuc-compatible programming leverages existing programmer expertise and reduces training investment for shops already running Fanuc-controlled equipment
20 mm maximum bar capacity covers the full range of medical, electronic, and hydraulic precision parts where multi-spindle economics are most compelling

Limitations

Six-spindle configuration limits throughput compared to eight-spindle systems (Tornos Sigma 8, Index MS 16) — maximum productive positions available per index is lower
20 mm maximum bar diameter excludes medium-sized precision parts — shops needing up to 32 mm or 45 mm capacity require different machines
CNC multi-spindle cycle times on simple parts may be marginally slower than cam-driven equivalents, since servo slide movements are not as instantaneous as cam-driven actuation

Best For

Medical device and dental implant manufacturers producing small-diameter precision components at high volumes where weekly part changeover makes cam-driven systems impractical Electronics and connector manufacturers producing threaded inserts, standoffs, and precision hardware from 1–20 mm bar stock at 100,000+ parts/month volumes Shops transitioning from single-spindle Swiss turning to multi-spindle production who want Fanuc-compatible CNC to leverage existing programmer training and toolpath knowledge

Frequently Asked Questions

01 What does a Star Micronics SC-20 cost?

New SC-20 machines typically price between $500,000 and $900,000 depending on configuration, back-working units, and bar feeder type. The fully CNC architecture eliminates cam tooling costs that add significantly to cam-driven machine setup costs.

02 How does the SC-20 compare to a Swiss-type single-spindle Star lathe?

A Swiss-type single-spindle Star lathe offers maximum flexibility for complex, low-volume precision parts. The SC-20 trades some geometric flexibility for raw throughput — it produces 4–6x more parts per hour on suitable high-volume families. The SC-20 is the right choice when volumes exceed what single-spindle equipment can support economically.

03 What materials can the SC-20 machine?

The SC-20 handles free-cutting steel, stainless steel, brass, aluminum, titanium, and engineering plastics. Material machinability affects achievable cycle times — free-cutting brass and aluminum achieve the fastest cycles, while stainless and titanium require reduced speeds and feeds.