DMG Mori GM 20|6

$550,000 - $800,000 Updated 2026-03-19

Key Specifications

Max Spindle

5,000 RPM per spindle

Max Workpiece ⌀

25 mm (1.0 in)

number of spindles

bar capacity

25 mm (1.0 in)

max workpiece length

100 mm (3.9 in)

x axis travel

42 mm (1.7 in)

Overview

The DMG Mori GM 20|6 is a 6-spindle CNC multi-spindle automatic lathe designed for high-volume production of parts up to 25 mm (1.0 in) bar diameter. It occupies the middle position in the GM range between the smaller GM 16|6 and the larger GM 35ISM, offering the ideal bar capacity for common automotive fasteners, hydraulic fittings, and connector components.

The GM 20|6 features 6 independently driven spindles reaching 5,000 RPM. While slower than the GM 16|6's 9,000 RPM, the 5,000 RPM speed is optimized for the larger bar diameters this machine handles. X-axis travel is 42 mm (1.7 in) and Z-axis travel is 50 mm (2.0 in), with a maximum workpiece length of 100 mm (3.9 in). Four compound-rest slides provide tooling positions for complex multi-operation parts.

The adjustable minimum cycle time under 1.4 seconds makes the GM 20|6 exceptionally productive for its size class. Six simultaneous spindle positions mean the machine is performing six different operations concurrently, producing a finished part with every index of the spindle drum. This throughput rate is unmatched by any combination of single-spindle or twin-spindle machines.

The monoblock construction with oil-cooled spindle bearings delivers the thermal stability required for 24/7 production. The Siemens 840D sl control handles the complex synchronization of up to 31 CNC axes. Back-working capability with C-axis enables complete part machining without secondary operations.

New GM 20|6 machines price between $550,000 and $800,000. The GM 20|6 competes with the INDEX MS22C, Tornos MultiSwiss 6x26, and other CNC multi-spindle automatics in the 20-25 mm bar class. Specs sourced from DMG Mori published data.

Full Specifications

Parameter	Value
Number Of Spindles	6
Bar Capacity	25 mm (1.0 in)
Max Spindle Speed	5,000 RPM per spindle
Max Workpiece Diameter	25 mm (1.0 in)
Max Workpiece Length	100 mm (3.9 in)
X Axis Travel	42 mm (1.7 in)
Z Axis Travel	50 mm (2.0 in)
Compound Rest Slides	4
Minimum Cycle Time	< 1.4 sec
Spindle Bearing Cooling	Oil-cooled
Construction	Monoblock
CNC Control	Siemens 840D sl
Machine Weight	9,500 kg (20,944 lb)
25 Mm	1 in.
100 Mm	3.9 in.
42 Mm	1.7 in.
50 Mm	2 in.

Specifications sourced from us.dmgmori.com — verified 2026-03-28

Strengths & Limitations

Strengths

25 mm bar capacity covers the most common size range for automotive fasteners, hydraulic fittings, and precision connectors
Sub-1.4 second minimum cycle time with 6 simultaneous operations delivers per-part throughput no single-spindle machine can match
Monoblock construction with oil-cooled bearings provides thermal stability for consistent accuracy across multi-shift production
Gildemeister multi-spindle heritage ensures a proven design refined over 70+ years of production experience
Siemens 840D sl control handles up to 31 CNC axes for complex synchronized multi-spindle operations
Back-working with C-axis enables complete part machining without secondary handling or fixturing

Limitations

5,000 RPM spindle speed is lower than the GM 16|6, which can limit surface speed optimization on smaller-diameter parts within the range
At $550,000-$800,000, the investment requires production volumes exceeding 50,000 pieces to justify over single-spindle alternatives
Setup times of 6-10 hours for full changeover make the GM 20|6 impractical for batch sizes below 10,000-20,000 pieces
Multi-spindle programming requires specialized operators with experience that most job shops do not have on staff

Best For

Automotive tier-1 suppliers producing fasteners, ABS sensor components, fuel rail fittings, and small drivetrain parts in high volumes Hydraulic and pneumatic component manufacturers running valve bodies, spool valves, and high-pressure fittings up to 25 mm diameter Medical device companies mass-producing implant screws, dental abutments, and surgical instrument components Electrical connector manufacturers producing contact pins, sockets, and housing components in brass, copper, and stainless Any production facility running 50,000+ identical parts per lot where multi-spindle throughput drives down per-part cost

Frequently Asked Questions

01 What does a new DMG Mori GM 20|6 cost?

New pricing runs $550,000-$800,000 depending on configuration. Adding back-working spindle, additional cross slides, and high-pressure coolant systems push toward the higher end. Used units from 2010-2020 trade between $250,000 and $500,000.

02 GM 20|6 vs GM 16|6 — which should I choose?

Bar capacity is the primary differentiator. The GM 16|6 handles up to 16 mm at 9,000 RPM; the GM 20|6 handles up to 25 mm at 5,000 RPM. If your parts fit within 16 mm, the 16|6 delivers faster cycle times. If you need 17-25 mm capacity, the 20|6 is your machine.

03 How does the GM 20|6 compare to the INDEX MS22C?

Both are 6-spindle CNC multi-spindle automatics targeting similar bar sizes. The INDEX MS22C offers more modern programming through VirtualLine software and is generally considered easier to set up. The GM 20|6 counters with Gildemeister heritage, robust monoblock construction, and DMG Mori service support. Performance is comparable.

04 Multi-spindle vs Swiss-type — when does each make sense?

Swiss-type machines (like the SPRINT series) excel at complex, long slender parts with fast changeover. Multi-spindle machines like the GM 20|6 win on per-part cost at volumes above 50,000 pieces due to 6 simultaneous operations. For high-mix/low-volume work, Swiss-type is more flexible. For dedicated high-volume production, multi-spindle is more economical.