DN Solutions SMX 3100ST

Est. $350,000 - $500,000 Updated 2026-08-10

Key Specifications

Max Turn Length

1,540 mm (61 in)

chuck size

12 inch

max turning diameter

660 mm (26 in)

main spindle speed max

3,000 r/min

main spindle power max

30 kW (40 hp)

main spindle torque max

1,300 N·m (959 ft-lb)

Overview

The DN Solutions SMX 3100ST is a horizontal multi-tasking machine with two turning spindles, a tilting B-axis milling head and a 12-station lower turret. The ST suffix marks that combination: a part can be turned on the main spindle while the lower turret cuts at the same time, then passed to the sub spindle so the back end is finished without a manual re-chuck.

Capacity is built around a 12 inch chuck, 660 mm (26 in) of maximum turning diameter and 1,540 mm (61 in) of maximum turning length. That envelope covers substantial shaft and flange work rather than small bar parts, and the length figure in particular puts the machine into territory usually reserved for a dedicated long-bed lathe.

The spindles are the strongest specification here. The main spindle produces 1,300 N·m (959 ft-lb) at up to 3,000 r/min from a 30 kW (40 hp) drive. Thirteen hundred newton-metres is a heavy-turning figure — this is a machine set up to take a deep cut in alloy steel and stainless at large diameters, where torque rather than spindle speed governs what is achievable. The sub spindle is not a parts catcher either: 30 kW (40 hp), 724 N·m (534 ft-lb) and 4,000 r/min mean second-end operations can include genuine roughing rather than a facing cut and a chamfer, and that is usually what decides whether a part truly comes off the machine complete.

The 12-station lower turret is a high-rigidity servo unit, and it is what separates this machine from a simpler mill-turn: it provides a second, independently controlled cutting point rather than extra tool storage. B and C axes resolve to 0.0001°, so angular features and indexed positions are not the limiting factor on accuracy.

The machine is 5,790 mm long, 3,021 mm wide and 2,820 mm tall (228 × 119 × 111 in), weighing 18,500 kg (40,786 lb). That mass is what supports the torque figures above, and it means installation needs a properly prepared floor rather than levelling pads on an existing slab. It fits oil and gas, aerospace and heavy component shops where large shaft-type parts currently pass through a turning operation, a milling operation and a second turning setup.

Full Specifications

Parameter	Value
Chuck Size	12 inch
Max Turning Diameter	660 mm (26 in)
Max Turning Length	1,540 mm (61 in)
Main Spindle Speed Max	3,000 r/min
Main Spindle Power Max	30 kW (40 hp)
Main Spindle Torque Max	1,300 N·m (959 ft-lb)
Sub Spindle Speed Max	4,000 r/min
Sub Spindle Power Max	30 kW (40 hp)
Sub Spindle Torque Max	724 N·m (534 ft-lb)
Lower Turret	12-station high-rigidity servo turret
B Axis C Axis Resolution	0.0001°
Machine Length	5,790 mm (228 in)
Machine Height	2,820 mm (111 in)
Machine Width	3,021 mm (119 in)
Machine Weight	18,500 kg (40,786 lb)

Specifications sourced from www.dn-solutions.com — verified 2026-08-09

Strengths & Limitations

Strengths

Main spindle torque of 1,300 N·m (959 ft-lb) from a 30 kW (40 hp) drive is a heavy-turning figure - this machine takes a deep cut in alloy steel and stainless at large diameters
The sub spindle is not a parts catcher: 30 kW (40 hp), 724 N·m (534 ft-lb) and 4,000 r/min mean second-end operations can include genuine roughing
1,540 mm (61 in) of maximum turning length on a 12 inch chuck puts the machine into territory usually reserved for a dedicated long-bed lathe
The 12-station lower turret is a high-rigidity servo unit - a second, independently controlled cutting point rather than extra tool storage
B and C axes resolve to 0.0001°, so angular features and indexed positions are not the limiting factor on accuracy
At 18,500 kg (40,786 lb) the machine has the mass to support those torque figures rather than merely quote them

Limitations

Main spindle speed tops out at 3,000 r/min, which is the trade for the torque - small-diameter high-speed turning is not what this machine is set up for
Maximum turning diameter is 660 mm (26 in), so the bed reaches further than the swing does; long slender work will need steady support
The machine is 5,790 mm long and 3,021 mm wide at 2,820 mm tall (228 x 119 x 111 in), which is a substantial floor commitment
18,500 kg (40,786 lb) means installation needs a properly prepared floor rather than levelling pads on an existing slab
Two spindles, a B-axis milling head and an independently controlled lower turret make four things to coordinate, and the machine only repays that complexity when parts genuinely use the concurrency

Best For

Large shaft-type parts that currently pass through a turning operation, a milling operation and a second turning setup Oil and gas work - valve bodies, connectors and downhole components with OD and ID features plus cross-holes Aerospace landing gear, structural and turbine components up to 1,540 mm long Heavy component work where 1,300 N·m of turning torque, not spindle speed, decides what is achievable Parts that need both ends finished on a single datum Long cycles where the lower turret's second cutting point can overlap with milling

Frequently Asked Questions

01 What size work does the SMX 3100ST handle?

It is built around a 12 inch chuck, with 660 mm (26 in) of maximum turning diameter and 1,540 mm (61 in) of maximum turning length. That envelope covers substantial shaft and flange work rather than small bar parts, and the length figure in particular puts the machine into territory usually reserved for a dedicated long-bed lathe.

02 What does the ST suffix mean?

Two turning spindles plus a lower turret. A part can be turned on the main spindle while the 12-station lower turret cuts at the same time, then passed to the sub spindle so the back end is finished without a manual re-chuck. That combination is what separates this from a simpler mill-turn machine.

03 Is the sub spindle capable of real work?

Yes, and that is rather the point of it. The sub spindle is rated 30 kW (40 hp) with 724 N·m (534 ft-lb) to 4,000 r/min - matched on power to the main spindle. Second-end operations can therefore include genuine roughing rather than a facing cut and a chamfer, which is usually what decides whether a part truly comes off the machine complete.

04 Why is the main spindle limited to 3,000 r/min?

Because it is a torque machine. It produces 1,300 N·m (959 ft-lb) from a 30 kW (40 hp) drive, which is set up for deep cuts in alloy steel and stainless at large diameters, where torque rather than spindle speed governs what is achievable. Small-diameter high-speed turning is the trade-off you accept for that.

05 What accuracy do the rotary axes hold?

B and C axes resolve to 0.0001°. In practice that means angular features and indexed positions are not the limiting factor on part accuracy; workholding, thermal conditions and tooling usually are, as on any machine of this size.

06 What does installation involve?

The machine is 5,790 mm long, 3,021 mm wide and 2,820 mm tall (228 x 119 x 111 in), weighing 18,500 kg (40,786 lb). That mass is what supports the torque figures, and it also means a properly prepared floor rather than levelling pads on an existing slab. Allow access along the full length for loading long shafts.