Citizen Miyano BNA-42MSY

$170,000 - $250,000 Updated 2025-03-15

Key Specifications

Max Spindle

SP1

max bar capacity sp1

42 mm (1.65 in)

max bar capacity sp2

34 mm (1.34 in), 42 mm optional

max machining length

100 mm (3.94 in)

main spindle speed

6,000 RPM

main spindle power

11/7.5 kW (15/10 hp)

Overview

The Citizen Miyano BNA-42MSY is a dual-spindle, single-turret fixed-headstock CNC automatic lathe with enhanced milling capability for bar stock up to 42 mm diameter. The MSY designation — Milling, Sub-spindle, Y-axis — signals a machine built for parts that demand serious cross-milling, drilling, and tapping alongside precision turning, all completed in a single cycle from bar.

The main spindle (SP1) reaches 6,000 RPM with 11/7.5 kW (15/10 hp), while the sub-spindle (SP2) runs to 5,000 RPM with 5.5/3.7 kW (7.5/5 hp). The sub-spindle accepts bar up to 34 mm diameter (42 mm optional) and travels independently on X2 and Z2 axes, enabling simultaneous front-and-back machining through Citizen's superimposition control. The 8-station turret uses a half-indexing mechanism to effectively double tool positions, and all 8 stations accept live tools running at 6,000 RPM with 1.0 kW (12 Nm) of rotary tool power.

Axis travels measure 140 mm on X1, 235 mm on Z1, and +/-35 mm on Y1, with the sub-spindle offering 129 mm on X2 and 360 mm on Z2. Rapids hit 20 m/min on X1, Z1, and Z2, with 12 m/min on Y1 and X2. Maximum machining length is 100 mm. The compact footprint of 2,278 x 1,450 mm and 3,000 kg weight make the BNA-42MSY one of the most space-efficient dual-spindle mill-turn machines in its class.

The MSY variant is the step up from the SY for shops that need more aggressive milling capability. The half-indexing turret mechanism provides effectively 16 tool positions from 8 physical stations, which is a different philosophy from the SY's 12-station turret — fewer individual stations but doubled effective positions for shops that can share tool holders between adjacent indexes.

Typical applications include medical implant components, automotive fuel system parts, hydraulic fittings with complex cross-holes, and electronic connector housings where milling features represent a significant portion of the total machining cycle. The superimposition control is particularly effective at overlapping backworking operations with front machining to squeeze maximum productivity from the single-turret design.

The current MSY2 generation brings input power of 29 kVA and improved rigidity over earlier generations. Direct competitors include the Star SR-38 in the sub-spindle turning center space and the Nakamura-Tome SC-200 for similar mill-turn applications.

Full Specifications

Parameter	Value
Max Bar Capacity Sp1	42 mm (1.65 in)
Max Bar Capacity Sp2	34 mm (1.34 in), 42 mm optional
Max Machining Length	100 mm (3.94 in)
Main Spindle Speed	6,000 RPM
Main Spindle Power	11/7.5 kW (15/10 hp)
Sub Spindle Speed	5,000 RPM
Sub Spindle Power	5.5/3.7 kW (7.5/5 hp)
Turret Stations	8 (half-indexing for 16 effective positions)
Live Tool Stations	8
Live Tool Speed	6,000 RPM
Live Tool Power	1.0 kW (12 Nm)
Travel X1	140 mm (5.51 in)
Travel Z1	235 mm (9.25 in)
Travel Y1	70 mm (+/-35 mm)
Travel X2	129 mm (5.08 in)
Travel Z2	360 mm (14.17 in)
Rapid Traverse Xz	20 m/min (787 ipm)
Rapid Traverse Y	12 m/min (472 ipm)
Machine Weight	3,000kg
Floor Space	2,388×1,450mm
Power Consumption	29 kVA
CNC Control	Mitsubishi CNC
Items	BNA-42MSY2
Maximum Machining Diameter Of Bar Work	SP1
Sp2	5,000min-1
Maximum Machining Length	100mm
Spindle Motor	SP1
Max Spindle Speed	SP1
Type Of Turret	8St.Turret(half-indexing mechanism)
Shank Height Of Square Turning Tool	20mm Sq.
Diameter Of Drill Shank	25mm Dia.
Rapid Feed Rate	Z1 axis
X1 Axis	20m/min
Y1 Axis	12m/min
Z2 Axis	20m/min
X2 Axis	12m/min
Maximum Number Of Revolving Tool	8
Machine Height	1,620mm
Sliding Headstock Type	A20
Bar Work	BNC42
Turning Machine	BNA42CY
High Precision Turning Machines	BNA42SY
Multi Station Machining Cell	MC20 III
Maximum Machining Diameter Of Bar Work Sp1	42mm Dia.
Maximum Machining Diameter Of Bar Work Sp2	34mm Dia.
Spindle Motor Sp1	11/7.5kW
Spindle Motor Sp2	5.5/3.7kW
Spindle Speed Sp1	6,000min-1
Spindle Speed Sp2	5,000min-1
Rapid Feed Rate Z1 Axis	20m/min
Rapid Feed Rate X1 Axis	20m/min
Rapid Feed Rate Y1 Axis	12m/min
Rapid Feed Rate Z2 Axis	20m/min
Rapid Feed Rate X2 Axis	12m/min
Inquiries	Feel free to get in touch with us by phone or online if you have any questions or need advice about any of our products or services.

Specifications sourced from cmj.citizen.co.jp — verified 2026-03-28

Strengths & Limitations

Strengths

Half-indexing turret mechanism effectively doubles the 8-station turret to 16 tool positions, providing excellent tooling density in a compact single-turret design
6,000 RPM live tool speed with dedicated milling capability delivers stronger cross-milling performance than the standard SY variant's 5,000 RPM rotary tools
Superimposition control enables simultaneous front-and-back machining with the single turret, reducing cycle times by 15-30% on parts with significant backworking
Extremely compact 2,278 x 1,450 mm footprint and 3,000 kg weight make it one of the smallest dual-spindle mill-turn machines available in the 42 mm class
Independent X2 axis on the sub-spindle enables true overlap machining where both spindles work simultaneously during different phases of the cycle
Proven Miyano fixed-headstock platform with cast iron bed construction delivers the rigidity needed for tight-tolerance medical and aerospace components

Limitations

34 mm standard sub-spindle capacity is smaller than the 42 mm main spindle, limiting backworking on larger-diameter parts without the optional upgrade
8 physical turret stations is fewer than the 12-station SY variant, and the half-indexing mechanism requires careful tool layout planning to maximize effective positions
1.0 kW (12 Nm) live tool power is modest for heavy milling cuts; shops doing extensive cross-milling in hardened materials may find it limiting
100 mm maximum machining length restricts the machine to short, compact parts only
Single turret shared between two spindles means tool allocation between front and back operations requires careful optimization to minimize idle time

Best For

Medical device manufacturers producing implant components, bone screws, and instrument fittings requiring extensive milling features from 42 mm bar stock Automotive fuel system component production where cross-drilling, hexagonal profiles, and milled flats are integral to the part design Hydraulic fitting manufacturers needing complete front-and-back machining with multiple cross-holes and milled features in a single cycle Shops with limited floor space that need full dual-spindle mill-turn capability in the smallest possible footprint High-volume production of electronic connector housings and RF components requiring tight tolerances and multiple milling operations Contract manufacturers upgrading from basic SY-type machines that need more aggressive milling capability without stepping up to a twin-turret platform

Frequently Asked Questions

01 What does a new Citizen Miyano BNA-42MSY cost?

New BNA-42MSY2 machines typically range from $170,000 to $250,000 depending on tooling, high-pressure coolant, bar feeder, and parts catcher options. Used BNA-42MSY machines from 2013-2020 sell for $70,000-$150,000 depending on generation, hours, and condition. The MSY commands a premium over the standard SY for its enhanced milling capability.

02 How does the half-indexing turret work on the BNA-42MSY?

The half-indexing mechanism allows the 8-station turret to stop at intermediate positions between the primary stations, effectively providing 16 tool positions. Adjacent tools can be mounted on the same station holder at different half-index positions. This requires careful planning of tool layout but delivers high tooling density from a compact turret.

03 What is the difference between the BNA-42MSY and the BNA-42DHY?

The DHY (Dual turret, H-axis, Y-axis) has two separate turrets — an 8-station main turret and a 6-station sub turret — allowing truly simultaneous independent machining on both spindles. The MSY uses a single turret with superimposition control. The DHY is more capable but also more complex and expensive. Choose the MSY for simpler programming and lower cost; choose the DHY for maximum multi-tool simultaneous cutting.

04 Can the BNA-42MSY run unattended with a bar feeder?

Yes. The BNA-42MSY pairs well with magazine bar feeders like the Edge M-542 or LNS Quick Load Servo for lights-out production. The sub-spindle pickup and parts catcher handle completed parts automatically. Budget for high-pressure coolant and a mist collector for reliable unattended operation, especially when running stainless steel or titanium.

05 What control system does the BNA-42MSY use?

The BNA-42MSY runs on a Mitsubishi CNC control with superimposition capability, C-axis interpolation, rigid tapping, and milling interpolation. The control handles the synchronization between main and sub-spindle operations and the half-indexing turret management. Programming is similar to other Mitsubishi-controlled Citizen machines.