Citizen Miyano BNA-42SY

$150,000 - $220,000 Updated 2025-03-15

Key Specifications

X Travel

140 mm (5.51 in)

Max Spindle

SP1

Spindle Power

SP1

max bar capacity sp1

42 mm (1.65 in)

max bar capacity sp2

34 mm (1.34 in)

max machining length

100mm

Overview

The Citizen Miyano BNA-42SY is a dual-spindle, single-turret fixed-headstock CNC automatic lathe built for complete front-and-back machining of bar stock up to 42 mm diameter. The SY designation means sub-spindle plus Y-axis, giving the machine full mill-turn capability in a compact footprint that Miyano has refined over multiple generations.

The main spindle (SP1) runs from 60 to 6,000 RPM with an 11/7.5 kW (15/10 hp) motor, while the sub-spindle (SP2) reaches 5,000 RPM with 5.5/3.7 kW (7.5/5 hp). The sub-spindle accepts parts up to 34 mm diameter and travels independently on a Z2 axis with 360 mm of stroke, enabling synchronized part pickup and backworking operations. This dual-spindle architecture eliminates the need for a separate second-operation machine for most bar-fed parts.

The 12-station turret with Y-axis capability accepts live tools at all 12 positions, running up to 5,000 RPM with 2.8/1.0 kW of rotary tool power. Y-axis travel of 70 mm (+/-35 mm) enables off-center drilling, milling, and tapping for flats, keyways, and eccentric features. Superimposition control allows simultaneous machining on both spindles using the single turret, overlapping front and back operations to reduce cycle times significantly.

Axis travels measure 140 mm on X, 285 mm on Z1, and 360 mm on the sub-spindle Z2 axis, with rapids of 20 m/min on X, Z, and Z2, and 12 m/min on Y. Maximum machining length is 100 mm per chucking. The machine weighs 3,880 kg with a floor space requirement of 2,350 x 1,433 mm — compact enough for shops adding mill-turn capability without major floor plan changes.

The BNA-42SY sits in the sweet spot of the Miyano lineup for shops running small precision parts in moderate to high volumes. It handles medical components, automotive fittings, hydraulic connectors, and electronic housings that need complete machining from bar stock in a single cycle. The superimposition capability is particularly valuable for reducing cycle times on parts where backworking operations would otherwise idle the main spindle.

Direct competitors include the Nakamura-Tome SC-200 and Tsugami B0386-III. The Miyano's 12-position all-live turret with Y-axis and proven superimposition control give it strong tooling density and cycle time advantages in its size class.

Full Specifications

Parameter	Value
Max Bar Capacity Sp1	42 mm (1.65 in)
Max Bar Capacity Sp2	34 mm (1.34 in)
Max Machining Length	100mm
Main Spindle Speed	60 - 6,000 RPM
Main Spindle Power	11/7.5 kW (15/10 hp)
Sub Spindle Speed	50 - 5,000 RPM
Sub Spindle Power	5.5/3.7 kW (7.5/5 hp)
Turret Stations	12
Live Tool Stations	12
Live Tool Speed	5,000 RPM
Live Tool Power	2.8/1.0 kW
X-Axis Travel	140 mm (5.51 in)
Travel Z1	285 mm (11.22 in)
Travel Z2	360 mm (14.17 in)
Y Axis Travel	70 mm (+/-35 mm)
Rapid Traverse Xz	20 m/min (787 ipm)
Rapid Traverse Y	12 m/min (472 ipm)
Machine Weight	3,880kg
Floor Space	2,350 x 1,433 mm
Power Consumption	26 kVA
CNC Control	Mitsubishi CNC
Item	BNA-42SY
Standard Machining Diameter	SP1
Sp2	5.5/3.7kW（15min/cont.）
Turret Slide Travel Distance	X axis
Z Axis	20m/min
Y Axis	12m/min
Number Of Spindles	2
Max Spindle Speed	SP1
Collet Chuck Size	SP1
Number Of Tool Posts	1
Type Of Tool Post	12 ST.
Dimensions Of Tools Used	20mm Sq.
Dimensions Of Tool Post Holes	25mm Dia.
Number Of Installed Rotary Tools	Max.12
Rotating Speed Of Rotary Tools	50 - 5,000min-1
Rapid Feed Rate	X axis
B Axis	20m/min
Spindle Motor Power	SP1
Rotary Tools Motor	2.8/1.0kW
Rated Power Consumption	26kVA
Machine Height	1,745mm
Required Floor Surface Area	W2,350 × 1,433mm
Sliding Headstock Type	A20
Bar Work	BNC42
Turning Machine	BNA42CY
High Precision Turning Machines	BNA42SY
Multi Station Machining Cell	MC20 III
Standard Machining Diameter Sp1	42mm Dia.
Standard Machining Diameter Sp2	34mm Dia.
Turret Slide Travel Distance X Axis	140mm
Turret Slide Travel Distance Z Axis	285mm
Turret Slide Travel Distance Y Axis	70（±35）mm
Spindle Speed Sp1	60 - 6,000min-1
Spindle Speed Sp2	50 - 5,000min-1
Collet Chuck Size Sp1	5"
Collet Chuck Size Sp2	4"
Rapid Feed Rate X Axis	20m/min
Rapid Feed Rate Z Axis	20m/min
Rapid Feed Rate Y Axis	12m/min
Rapid Feed Rate B Axis	20m/min
Spindle Motor Sp1	11/7.5/5.5kW（15%/15min/cont.）
Spindle Motor Sp2	5.5/3.7kW（15min/cont.）
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

Dual-spindle architecture with independent Z2 axis enables complete front-and-back machining from bar stock in a single cycle, eliminating second-operation handling entirely
All 12 turret stations accept live tools at 5,000 RPM, providing maximum tooling density without sacrificing turning positions to static-only stations
Superimposition control overlaps front and back operations on the single turret, reducing cycle times by 15-30% on parts with significant backworking requirements
Y-axis travel of 70 mm adds off-center milling, drilling, and tapping capability for complex features like flats, keyways, and hexagonal profiles
Compact 2,350 x 1,433 mm footprint delivers full dual-spindle mill-turn capability without the floor space demands of larger multi-tasking machines
6,000 RPM main spindle provides adequate speed for both steel roughing and aluminum finish turning across the 42 mm bar capacity range

Limitations

Sub-spindle bar capacity limited to 34 mm versus 42 mm on the main spindle, restricting backworking on larger-diameter parts unless the optional 42 mm sub-spindle is fitted
100 mm maximum machining length is relatively short, limiting the machine to compact parts and ruling out longer shaft-type components
Single turret shared between two spindles means backworking tool selection is limited compared to twin-turret machines like the BNE or BNJ series
5,000 RPM live tool speed is competitive but below the 6,000 RPM available on newer-generation Miyano platforms for demanding cross-milling work
No LFV chip-breaking technology standard on this model, which can be a limitation for unattended production of gummy stainless steel and titanium parts

Best For

Medical device manufacturers producing complete small components like bone screws, dental abutments, and instrument fittings from bar stock in one cycle Automotive shops running high-volume precision fittings, sensor housings, and connector bodies that need front-and-back machining Hydraulic and pneumatic component manufacturers producing valve bodies, fittings, and couplings with cross-holes and back-end features Contract manufacturers needing a versatile 42 mm bar-fed mill-turn machine for high-mix production with short setup times Shops replacing separate first-operation and second-operation lathe setups to consolidate into a single done-in-one process Electronics manufacturers producing precision connector housings and RF components requiring tight concentricity between front and back features

Frequently Asked Questions

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

New pricing for the BNA-42SY typically ranges from $150,000 to $220,000 depending on tooling configuration, high-pressure coolant, parts catcher, and bar feeder. Used machines from 2014-2020 sell for $60,000-$130,000 depending on hours, spindle condition, and included tooling. The single-turret dual-spindle design positions it below the more complex MSY and DHY variants in price.

02 How does the BNA-42SY differ from the BNA-42MSY?

The MSY adds a milling spindle designation with enhanced rotary tool capability, an 8-station turret with half-indexing for 16 effective positions, and improved milling power. The SY has a 12-station turret with all-live capability at 5,000 RPM. Choose the SY for maximum tool count and general-purpose mill-turn work; choose the MSY for more demanding milling operations that need higher rotary tool power.

03 Can the BNA-42SY handle 42 mm bar on both spindles?

The standard sub-spindle accepts up to 34 mm diameter. An optional 42 mm sub-spindle configuration is available for shops that need full-diameter backworking. Check with your Citizen distributor for the specific sub-spindle upgrade availability for your machine generation.

04 What bar feeder works with the BNA-42SY?

The BNA-42SY is compatible with magazine-style bar feeders from Edge Technologies, LNS, and Iemca in the 42 mm capacity class. Edge M-542 and LNS Quick Load Servo 80 are common pairings. The bar feeder interface is straightforward, and most shops run 6-foot or 12-foot magazine loaders for lights-out production.

05 How does superimposition control work on the BNA-42SY?

Superimposition synchronizes the sub-spindle movement with the turret to enable simultaneous machining on both spindles using the single turret. While the turret is cutting on the main spindle, the sub-spindle can move independently to position for its next operation. This overlapping of front and back operations reduces cycle time by 15-30% compared to sequential processing.

06 What maintenance schedule does the BNA-42SY require?

Standard maintenance includes daily chip removal and coolant level checks, weekly way lube and hydraulic oil inspection, and annual spindle bearing preload verification. The turret indexing mechanism should be checked every 2,000-3,000 hours. Budget approximately $3,000-$6,000 per year for consumables, filters, and periodic service on a machine running two shifts.