Okuma LB2500 EX II

$125,000 - $185,000 Updated 2026-03-13

Key Specifications

Max Spindle

4,500 RPM

Rapid Traverse

25 m/min X, 30 m/min Z

Spindle Power

18.5/15 kW (25/20 hp)

Max Turn Length

150

Accuracy

±0.004 mm

Repeatability

±0.002 mm

Overview

The Okuma LB2500 EX II occupies a sweet spot in Okuma's turning center lineup, sitting between the smaller LB2000 EX and the mid-size LB3000 EX. It's designed for shops that need more swing and bar capacity than an 8-inch chuck lathe provides but don't need the full capability of the LB3000. The EX II generation brought refined thermal compensation, updated control software, and improved spindle bearing technology over the original EX.

Max turning diameter is 340 mm (13.4 in) with a swing over bed of 560 mm (22 in). Standard turning length is 500 mm (19.7 in), with 750 mm (29.5 in) and 1,000 mm (39.4 in) options for longer shaft work. The spindle delivers 18.5/15 kW (25/20 hp) at up to 4,500 RPM through a JIS A2-8 spindle nose. Bar capacity is 65 mm (2.56 in) on the standard bore, handling the majority of production bar stock without a spindle liner swap.

The LB2500 EX II uses Okuma's proven box way construction for both X and Z axes. The 12-station turret supports BMT tool mounting on M/MY variants, with driven tool speeds up to 6,000 RPM. The machine weighs approximately 4,500 kg (9,921 lb), providing solid thermal mass for stability.

Okuma's OSP-P300L control handles both standard G-code and One Touch IGF conversational programming. Thermo-Friendly Concept monitors and compensates for thermal growth in real time, which matters most on production runs exceeding 4 hours in shops without climate control.

The LB2500 EX II competes with the Mazak Quick Turn 250, DMG Mori NLX 2000, and Haas ST-20 in the mid-range turning center segment. It offers more spindle power than the Haas and better thermal stability than both the Mazak and DMG Mori at a competitive price point. Shops often choose it when the LB2000 EX is too small and the LB3000 EX is more machine than they need. Specs sourced from Okuma published data.

Full Specifications

Parameter	Value
Max Turning Diameter	410
Max Turning Length	150
Swing Over Bed	560 mm (22 in)
Max Spindle Speed	4,500 RPM
Spindle Motor Power	18.5/15 kW (25/20 hp)
Spindle Nose	JIS A2-8
Chuck Size	10 in (254 mm)
Bar Capacity	65 mm (2.56 in)
Turret Stations	12
X Axis Travel	200 mm (7.9 in)
Z Axis Travel	560 mm (22 in)
Rapid Traverse Rate	25 m/min X, 30 m/min Z
Positioning Accuracy	±0.004 mm
Repeatability	±0.002 mm
Machine Weight	4,500 kg (9,921 lb)
CNC Control	Okuma OSP-P300L
Speed Range	45~5,000
Rapid Traverse X Z	25/30
Standard Power	22/15
Okuma Global Repair Center	Charlotte, North Carolina
Inches	Metric
Spindle Nose Type	JIS A2-6

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

Strengths & Limitations

Strengths

340 mm turning diameter fills the gap between compact 8-inch chuck lathes and full-size 10-inch platforms
18.5 kW spindle provides more power than competing Haas and Doosan models in this size class
Box way construction delivers superior rigidity and vibration damping for heavy roughing in tough materials
65 mm bar capacity covers the most common production bar stock sizes without spindle liner changes
Thermo-Friendly Concept maintains dimensional accuracy during multi-shift production without shop climate control
BMT turret mounting on M/MY variants provides rigid milling for done-in-one part processing

Limitations

4,500 RPM max spindle speed is lower than the LB2000 EX III's 5,000 RPM, limiting high-speed finishing on small diameters
Starting at $125K, it costs considerably more than a Haas ST-20 with comparable basic turning specs
OSP control requires retraining for shops standardized on Fanuc or Siemens
The LB2500 EX II is being superseded by the LB2500 EX III in some markets, which may affect long-term parts support

Best For

Production shops that need more swing than an 8-inch chuck lathe but don't need the full LB3000 EX platform Automotive and hydraulic component manufacturers running 65 mm and under bar stock in production volumes Shops holding 0.01 mm tolerances over 8+ hour runs where thermal stability directly affects scrap rates Facilities standardized on Okuma that need a mid-range lathe to complement LB3000 and LB4000 machines Job shops wanting box way rigidity for mixed material work including stainless, tool steel, and cast iron

Frequently Asked Questions

01 What does an Okuma LB2500 EX II cost?

New LB2500 EX II machines run $125,000-$185,000 depending on configuration. Base turning models start around $125,000-$140,000. MY configurations with Y-axis and driven tools push toward $170,000-$185,000. Used machines from 2016-2022 sell for $65,000-$100,000.

02 How does the LB2500 EX II compare to the LB3000 EX II?

The LB3000 EX II has a larger turning diameter (400 vs 340 mm), more spindle power (22 vs 18.5 kW), higher spindle speed (5,000 vs 4,500 RPM), and larger bar capacity (76 vs 65 mm). The LB2500 EX II costs about $10,000-$15,000 less for comparable configurations. Choose the LB2500 if your work fits within 340 mm diameter; step up to the LB3000 for larger parts.

03 What's the difference between the LB2500 EX and LB2500 EX II?

The EX II brought upgraded spindle bearings for improved thermal performance, refined Thermo-Friendly algorithms, updated OSP control software, and minor structural improvements. Existing LB2500 EX owners report the EX II reaches thermal stability faster after cold starts and holds tighter tolerances during extended production runs.

04 Can the LB2500 EX II handle shaft work?

Yes. With the 750 mm or 1,000 mm bed length option and tailstock, the LB2500 EX II handles shaft turning up to about 39 inches between centers. For shaft work beyond 1,000 mm, step up to the LB35 III or LB45 III with extended bed options.

05 Is the LB2500 EX II good for aerospace work?

Yes. The combination of box way rigidity, Thermo-Friendly thermal compensation, and ±0.002 mm repeatability makes it well-suited for aerospace shaft and fitting work. Many aerospace shops run the MY variant to complete turned-and-milled parts in one setup, reducing the tolerance stackup from multiple setups.