Starrag Bumotec s191H

$400,000 - $650,000 Updated 2026-03-15

Key Specifications

X Travel

200 mm (7.87 in)

Y Travel

160 mm (6.30 in)

Z Travel

250 mm (9.84 in)

Tool Capacity

90 positions

Accuracy

±0.002 mm (±0.00008 in)

Repeatability

±0.001 mm (±0.00004 in)

Overview

The Starrag Bumotec s191H is a 7-axis CNC mill-turn machining center designed for the complete machining of complex, high-precision parts in a single setup. Developed by Bumotec, a Swiss division of the Starrag Group, this machine is purpose-built for the watchmaking, medical device, and jewelry industries where micron-level accuracy on small, intricate components is non-negotiable. The s191H can handle turning, milling, drilling, tapping, and even engraving operations without unclamping the workpiece, delivering finished parts from bar stock in one hit.

The machine features a high-speed motorized spindle running up to 40,000 RPM with 12.5 kW of power, paired with a turning spindle capable of 6,000 RPM for lathe operations. X/Y/Z travels of 200 x 160 x 250 mm define a compact but optimized work envelope for parts up to approximately 65 mm diameter. The machine processes bar stock up to 32 mm diameter through its bar feeder interface, and can also work with blanks or previously roughed components. The 90-position tool magazine ensures that even the most complex parts can be completed without manual intervention for tool changes.

What sets the s191H apart from conventional mill-turn centers is its kinematic architecture. The 7-axis configuration (X, Y, Z, B-axis on the milling spindle, C-axis on the turning spindle, plus two additional axes for part manipulation) enables access to virtually any surface of the workpiece without manual repositioning. The machine achieves positioning accuracy within 2 microns and repeatability under 1 micron, specifications that meet the demands of Swiss watchmaking and medical implant manufacturing.

The Bumotec s191H competes with machines like the Willemin-Macodel 508MT and Citizen Cincom series, but occupies a unique niche: it's more of a micro machining center with turning capability than a lathe with milling. The Fanuc 31i-B5 CNC control handles the multi-axis synchronization with established reliability. New machines typically price between $400,000 and $650,000 depending on configuration, automation, and tooling packages. For shops producing complex watch components, dental abutments, or micro-surgical instruments, the s191H's ability to eliminate multiple setups across different machines justifies the investment through reduced handling, better accuracy, and shorter lead times.

Full Specifications

Parameter	Value
X-Axis Travel	200 mm (7.87 in)
Y-Axis Travel	160 mm (6.30 in)
Z-Axis Travel	250 mm (9.84 in)
Milling Spindle Speed	40,000 RPM
Milling Spindle Power	12.5 kW (16.8 hp)
Turning Spindle Speed	6,000 RPM
Bar Capacity	32 mm (1.26 in)
B Axis	Yes, continuous
C Axis	Yes, on turning spindle
Axes	7 CNC axes
Tool Capacity	90 positions
Positioning Accuracy	±0.002 mm (±0.00008 in)
Repeatability	±0.001 mm (±0.00004 in)
CNC Control	Fanuc 31i-B5
Machine Weight	5,500 kg (12,125 lb)

Specifications sourced from starrag.com — verified 2026-03-28

Strengths & Limitations

Strengths

7-axis configuration provides full access to all workpiece surfaces, enabling complete machining of complex parts in a single clamping without manual repositioning
40,000 RPM milling spindle delivers the surface speeds needed for micro-milling hard materials like titanium, cobalt chrome, and stainless steel at small diameters
90-position tool magazine supports complex multi-operation parts without stopping for manual tool changes, essential for lights-out production
Sub-2-micron positioning accuracy meets the stringent tolerance requirements of Swiss watchmaking and Class III medical device manufacturing
Bar stock processing up to 32 mm diameter combined with mill-turn capability eliminates the need for separate lathe and milling center setups
Compact footprint relative to capability — replaces multiple machines (lathe, mill, engraving) with a single integrated platform

Limitations

200 x 160 x 250 mm work envelope strictly limits the machine to small parts — anything over 65 mm diameter or moderate length is out of scope
Price point of $400K-$650K is steep for a machine with such a small work envelope, making it hard to justify unless you're running high-value parts
7-axis programming complexity requires operators and programmers with advanced multi-axis CAM skills — not a machine you hand to a junior operator
Starrag/Bumotec service presence in North America is limited compared to Japanese and German mainstream brands, potentially leading to longer support response times

Best For

Swiss watchmaking manufacturers producing cases, movements, bridges, and plates requiring micron-level accuracy across milled and turned features Medical device companies machining dental abutments, bone screws, spinal implants, and micro-surgical instruments from titanium and cobalt chrome bar stock Jewelry and luxury goods manufacturers producing complex small components with both rotational and prismatic features Aerospace micro-component production where multi-surface access and tight tolerances are required on small sensor housings and actuator components High-mix production environments running small complex parts that currently require setups on three or more different machines

Frequently Asked Questions

01 What types of parts is the Bumotec s191H designed for?

The s191H is designed for small, complex parts that require both turning and milling operations — typically under 65 mm diameter. Its core markets are Swiss watchmaking (cases, movement plates, bridges), medical devices (dental abutments, bone screws, spinal implants), and precision industrial components. The 7-axis architecture means parts that previously needed three or four setups across different machines can be completed in one clamping.

02 How does the s191H compare to a Swiss-type lathe?

While Swiss-type lathes like the Citizen Cincom series excel at high-volume production of turned parts with some milling capability, the s191H is fundamentally a milling center with turning capability. It offers a larger work envelope, more milling axes, and a 90-tool magazine compared to a typical Swiss lathe's 20-30 tools. Choose the s191H when milling complexity is high; choose a Swiss lathe when production volume and cycle time on turned parts are the priority.

03 What CNC control does the Bumotec s191H use?

The s191H runs on a Fanuc 31i-B5 CNC control, which is Fanuc's high-end platform for 5-axis and multi-axis applications. It handles the synchronization of all 7 axes, high-speed milling interpolation, and turning operations. The Fanuc platform is widely supported with established training programs and service networks worldwide.

04 Can the s191H run unattended?

Yes. With a bar feeder for continuous stock supply and the 90-position tool magazine, the s191H is well-suited for lights-out or lightly attended production. Bumotec also offers integrated automation solutions including part handling and palletization for blank-fed operations. The machine's done-in-one capability means finished parts come off without manual intervention between operations.

05 What does a Starrag Bumotec s191H cost?

New s191H machines typically price between $400,000 and $650,000 depending on spindle options, tool magazine size, automation, and bar feeder configuration. This is premium pricing for the work envelope, but reflects the machine's unique 7-axis capability and sub-2-micron accuracy. Used machines are rare on the secondary market due to limited production volumes and high demand in watchmaking and medical sectors.

06 What materials can the s191H machine?

The s191H handles a wide range of materials including stainless steels, titanium alloys (Ti-6Al-4V), cobalt chrome, brass, aluminum, and precious metals. The 40,000 RPM spindle provides the surface speeds needed for efficient micro-milling of hard materials with small-diameter tools. The machine is particularly strong on the bio-compatible alloys used in medical implants.