Okuma MULTUS B400II
Key Specifications
Tool Capacity
Rapid Traverse
max turning diameter
max machining length
main spindle speed
main spindle power
Overview
The Okuma MULTUS B400II is the mid-range workhorse of Okuma's MULTUS horizontal multitasking lineup, offering a significantly larger work envelope than the B200II for shops machining longer and larger-diameter parts. With a maximum turning diameter of 710 mm (28.0 in) and maximum machining length of 1,500 mm (59.1 in), it handles the shaft and housing work that is too long for the B200II while staying smaller and more affordable than the B750.
The main turning spindle delivers 30/22 kW (40/30 hp) at up to 3,800 RPM with 500 Nm (369 ft-lb) of torque through an A2-8 spindle nose with 80 mm (3.15 in) bar capacity. The milling spindle runs up to 12,000 RPM with 22/18.5 kW (30/25 hp) through a Capto C6 interface. The B-axis swings 225 degrees (-30 to +195 degrees) with direct-drive and 0.001-degree minimum increment.
X-axis travel is 480 mm (18.9 in), Y-axis is 200 mm (7.9 in), and Z-axis is 1,500 mm (59.1 in). The larger Y-axis range compared to the B200II (200 mm vs 130 mm) provides more off-center milling reach for features like keyways, flats, and off-center holes. Rapid traverse is 40 m/min on X and Z. The standard ATC holds 40 tools with options up to 120.
An optional sub-spindle and optional lower turret expand the machine's capability. The sub-spindle enables back-end machining for complete done-in-one parts. The lower turret adds simultaneous cutting capability for balance turning and roughing while the milling spindle handles finishing. Okuma's Thermo-Friendly Concept and Collision Avoidance System are standard.
The MULTUS B400II competes with the Mazak Integrex i-400, DMG Mori CTX beta 2000 TC, and Nakamura-Tome MX-250. Pricing runs $500,000-$750,000 new. Machine weight is approximately 18,000 kg (39,683 lb). It targets aerospace, oil and gas, and precision manufacturing shops running complex long parts that require turning, milling, and angular machining in a single setup.
Full Specifications
| Parameter | Value |
|---|---|
| Max Turning Diameter | Ø710 |
| Max Machining Length | 1,500 mm (59.1 in) |
| Main Spindle Speed | 3,800 RPM |
| Main Spindle Power | 30/22 kW (40/30 hp) |
| Main Spindle Torque | 500 Nm (369 ft-lb) |
| Spindle Nose | A2-8 |
| Bar Capacity | 80 mm (3.15 in) |
| Milling Spindle Speed | 12,000 RPM |
| Milling Spindle Power | 22/18.5 kW (30/25 hp) |
| Milling Tool Interface | Capto C6 |
| B Axis Range | -30° to +195° (225° swing, 0.001° increment) |
| X Axis Travel | 480 mm (18.9 in) |
| Y Axis Travel | 200 mm (7.9 in) |
| Z Axis Travel | 1,500 mm (59.1 in) |
| Tool Capacity | 40 (options: 60, 80, 120) |
| Rapid Traverse Rate | 40 m/min (X, Z) |
| Sub Spindle | Optional |
| Lower Turret | Optional |
| Machine Weight | 18,000 kg (39,683 lb) |
| CNC Control | Okuma OSP-P300SA |
| Speed Range | 38~3,800 [30~2,800] |
| Standard Power | VAC 22/15 |
| Rapid Traverse Xz Y | 40/26 |
| Okuma Global Repair Center | Charlotte, North Carolina |
| Inches | Metric |
| Spindle Nose Type | JIS A2-8 [JIS A2-11] |
Specifications sourced from okuma.com — verified 2026-03-28
Strengths & Limitations
Strengths
- 1,500 mm machining length handles long shafts, spools, and housing parts that the B200II cannot reach
- 200 mm Y-axis travel provides generous off-center milling reach for keyways, flats, and complex milled features
- 500 Nm main spindle torque enables aggressive roughing on large-diameter steel and alloy shaft work
- Optional sub-spindle plus optional lower turret create a full done-in-one platform with simultaneous cutting capability
- 40-120 tool ATC provides deep tool library for complex long parts requiring many different operations
- 80 mm bar capacity covers the broad range of bar stock sizes for mid-size production turning
Limitations
- Capital cost of $500,000-$750,000 fully configured requires consistent complex-part volume to justify the investment
- 18,000 kg machine weight requires substantial foundation preparation and careful rigging planning
- 3,800 RPM main spindle speed is adequate but slower than the B200II's 5,000 RPM for smaller-diameter aluminum work
- OSP control for multitasking with optional sub-spindle and lower turret creates significant programming complexity
- Larger footprint than the B200II may be a factor in shops with limited floor space
Best For
Frequently Asked Questions
01
A new MULTUS B400II starts around $500,000 in base configuration and can reach $750,000 with sub-spindle, lower turret, expanded tool magazine, and automation options. Used machines from 2016-2020 trade in the $250,000-$450,000 range depending on hours and configuration.
02
Both are 400-class multitasking machines with similar turning and milling capability. The Mazak uses MAZATROL SmoothAi with strong conversational programming. Okuma offers Thermo-Friendly Concept and Collision Avoidance as standard differentiators. The Mazak may offer 20,000 RPM milling options. Both machines are strong competitors with loyal user bases.
03
The B400II has 1,500 mm machining length versus 750 mm, 710 mm turning diameter versus 630 mm, 30 kW spindle versus 22 kW, 80 mm bar capacity versus 65 mm, 200 mm Y-axis versus 130 mm, and optional lower turret. The B400II is for longer and larger parts; the B200II is more compact and affordable.
04
The lower turret adds a second cutting point that can operate simultaneously with the milling spindle. Use cases include balance turning (roughing on the lower turret while finishing with the milling spindle), OD roughing while boring, and reducing cycle time on parts with many operations by running two tools at once.
05
Yes, the 1,500 mm machining length and 710 mm turning diameter cover many landing gear actuator housings, cylinders, and structural components. The B-axis milling spindle handles the angled features, cross-holes, and milled pockets typical of landing gear parts. The sub-spindle option enables back-end machining for complete parts.
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