Yamazaki Mazak Mill-Turn / Multi-Tasking Machines

Mazak INTEGREX i-400ST

$500,000 - $750,000 Updated 2026-03-17

Key Specifications

max turning diameter

658 mm (25.9 in)

max part length

1,519 mm (59.8 in)

main spindle speed

3,300 RPM

main spindle power

30 kW (40 hp)

sub spindle speed

4,000 RPM

sub spindle power

15 kW (20 hp)

Overview

The Mazak INTEGREX i-400ST is the highest-capability variant of the INTEGREX i-400 platform, adding both a second (sub) turning spindle and a lower turret to the base i-400's single-spindle, single-milling-head configuration. The "ST" suffix stands for Sub-spindle and Turret — these two additions transform the machine from a capable mill-turn into a simultaneous multi-tasking system that can perform turning, milling, and drilling on both ends of a workpiece at the same time.

The main turning spindle delivers 30 kW (40 hp) at 3,300 RPM through an A2-8 spindle nose with 102 mm (4.0 in) bar capacity. The second spindle matches the sub-spindle found on MSY-class lathes — typically 11-15 kW at 4,000-6,000 RPM with a 6-inch chuck — enabling automatic part transfer and simultaneous backworking. The lower turning turret operates in parallel with the upper milling head, allowing two tools to cut simultaneously and dramatically reducing cycle times on complex parts.

The upper milling spindle runs to 12,000 RPM (20,000 RPM optional) at 22 kW (30 hp) through a Capto C6 interface. The B-axis provides 240 degrees of tilt (−30° to +210°) with 0.0001-degree resolution. Combined with 250 mm of Y-axis travel and full C-axis rotation on both spindles, the i-400ST can perform 5-axis simultaneous contouring, full turning, and drilling across the entire workpiece in a single clamping.

The standard ATC holds 36 tools (72 or 110 optional) at Capto C6 shank. Machine weight is approximately 19,000 kg (41,888 lb). The i-400ST runs on MAZATROL SmoothAi CNC. It competes with the DMG Mori CTX beta TC and Okuma Multus B400II at the higher-capability end of the mill-turn segment. New machines carry pricing from $500,000 to $750,000 depending on configuration.

Full Specifications

Parameter	Value
Max Turning Diameter	658 mm (25.9 in)
Max Part Length	1,519 mm (59.8 in)
Main Spindle Speed	3,300 RPM
Main Spindle Power	30 kW (40 hp)
Sub Spindle Speed	4,000 RPM
Sub Spindle Power	15 kW (20 hp)
Milling Spindle Speed	12,000 RPM (20,000 RPM optional)
Milling Spindle Power	22 kW (30 hp)
Milling Spindle Taper	Capto C6
B Axis Range	240° (-30° to +210°)
B Axis Resolution	0.0001°
Y Axis Travel	250 mm (9.84 in)
Number Of Axes	9 (with lower turret and sub-spindle)
Bar Capacity	102 mm (4.0 in)
Chuck Size Main	10 in (A2-8)
Chuck Size Sub	6 in
Atc Tool Capacity	36 tools (72 or 110 optional)
Rapid Traverse Xz	50 m/min (1,969 ipm)
Machine Weight	19,000 kg (41,888 lb)
CNC Control	MAZATROL SmoothAi CNC

Strengths & Limitations

Strengths

Sub-spindle and lower turret together enable true simultaneous multi-tasking — turning, milling, and backworking happening at the same time, cutting total cycle time on complex parts by 30-50%
102 mm (4.0 in) bar capacity handles larger-diameter bar stock than most competing 5-axis mill-turns, opening up energy sector and oilfield component work
22 kW (30 hp) Capto C6 milling spindle at 12,000 RPM provides genuine machining center performance rather than auxiliary live tooling
240-degree B-axis with roller gear cam drive and 0.0001-degree resolution delivers zero-backlash angular positioning for complex aerospace and defense components
SmoothAi control with Ai Thermal Shield maintains dimensional accuracy during long simultaneous multi-tasking cycles on expensive workpieces
36 to 110-tool ATC eliminates manual tool change interruptions on complex multi-operation parts with deep tool libraries

Limitations

$500K-$750K investment is only justified for shops consistently eliminating four or more setups per part across significant production volume
19,000 kg (41,888 lb) machine weight demands serious foundation preparation, rigging expertise, and long-term floor space commitment
Programming a 9-axis machine with simultaneous upper milling and lower turning requires experienced CAM programmers; post-processor availability and configuration is a known pain point
3,300 RPM main turning spindle is slower than ideal for small-diameter high-speed turning on aluminum or non-ferrous parts
B-axis and sub-spindle synchronization requires careful verification after any crash or major alarm; recalibration is time-consuming without Mazak service support

Best For

Aerospace manufacturers producing complex shafts, structural components, and fitting hardware that require simultaneous 5-axis milling and turning on both ends Energy sector shops machining oilfield downhole components, valve bodies, and wellhead parts that need complete machining in a single setup at scale Defense contractors producing ordnance, guidance housings, and precision structural parts where done-in-one processing is mandatory for accuracy and traceability Job shops running high-value, high-complexity parts where the ability to run two tools simultaneously justifies the premium over a standard i-400 Production cells running lights-out with bar feeders on medium-to-large bar stock, leveraging simultaneous machining to offset the machine cost per part

Frequently Asked Questions

01 What is the difference between the INTEGREX i-400, i-400S, and i-400ST?

The base i-400 has a single turning spindle and the upper milling B-head. The i-400S adds a second (sub) spindle for automatic part transfer and backworking — enabling done-in-one machining of both ends. The i-400ST adds both the sub-spindle and a lower turning turret. The lower turret means two cutting tools can work the part simultaneously, dramatically reducing cycle time. The S and ST cost $100,000-$200,000 more than the base i-400 but pay back quickly on complex, high-value parts.

02 How much cycle time reduction does the lower turret provide?

It depends heavily on the part, but on multi-feature turned and milled parts, simultaneous machining with the lower turret and upper milling head can reduce total cycle time by 30-50%. The lower turret handles turning, grooving, threading, and boring while the upper B-head mills features — tasks that would otherwise be sequential. The more operations a part requires, the bigger the cycle time advantage.

03 What post processors are available for the i-400ST?

MAZATROL SmoothAi supports both conversational and EIA/ISO programming. For CAM-posted work, Mastercam, Siemens NX, and Hypermill offer verified i-400ST post processors. Third-party post processors vary significantly in quality — many shops use Mazak-verified posts exclusively for 9-axis synchronization to avoid crashes during simultaneous machining cycles. Mazak's own application engineering team can assist with post qualification.

04 Can the i-400ST run unattended overnight?

Yes. With a bar feeder matched to the 102 mm bore, NC tailstock for long workpieces, part catcher on the sub-spindle, and chip conveyor, the i-400ST is well-suited to lights-out production. SmoothAi tool life management, automatic tool compensation, and SMOOTH Monitor remote status monitoring support multi-shift unattended operation on complex multi-tasking programs.

05 How does the i-400ST compare to the DMG Mori CTX beta 1250 TC?

Both are high-capability mill-turn machining centers with sub-spindle and lower turret. The Mazak i-400ST uses a Capto C6 upper milling spindle with roller gear cam B-axis, paired with MAZATROL SmoothAi control. The DMG Mori CTX beta runs CELOS with a Fanuc or Siemens control underneath. Both machines are broadly comparable on specs; the Mazak typically offers stronger conversational programming capability while DMG Mori provides more control platform options. Dealer support in your region is often the deciding factor.