DMG Mori GMX 400
Key Specifications
Spindle Taper
Spindle Power
Max Turn Length
Accuracy
max tool length
max tool diameter
Overview
The DMG Mori GMX 400 is a 5-axis universal tool and cutter grinding machine designed for the precision manufacture and reconditioning of cutting tools — end mills, drills, reamers, hobs, and custom form tools — up to 400 mm (15.7 in) in length and 300 mm (11.8 in) in diameter. It targets tool manufacturers, precision grinding job shops, and large machining facilities that maintain their own cutting tool inventories in-house rather than outsourcing regrinding.
The machine's 5-axis kinematic configuration — three linear axes (X, Y, Z) and two rotary axes (A and C) — provides the full simultaneous grinding freedom required for complex flute geometries, relief angles, and chip breakers in a single setup. The grinding spindle runs at up to 12,000 RPM and accepts standard HSK-E50 (or alternative mounting options depending on configuration) wheel arbors, compatible with the standard CBN and diamond wheel systems used in production tool grinding.
A key feature of the GMX 400 is its integrated automatic wheel changer and dressing system. Automatic dressing ensures consistent wheel profiles throughout a production run, which is critical for maintaining the geometric accuracy and surface finish quality that cutting tool tolerances demand. The machine can store multiple wheel packs in the changer and swap between them during a grinding cycle without operator intervention.
Control is via Siemens Sinumerik 840D sl or the NUMROTO grinding software platform — the latter being the industry-standard NC system for tool grinding, offering a library of pre-programmed tool geometries that drastically reduces setup time for standard tool families. The machine is compatible with automated loading systems for high-volume tool production environments.
Full Specifications
| Parameter | Value |
|---|---|
| Max Tool Length | 400 mm (15.7 in) |
| Max Tool Diameter | 300 mm (11.8 in) |
| Max Workpiece Weight | 20 kg (44 lb) |
| Grinding Spindle Speed | up to 12,000 RPM |
| Spindle Motor Power | 15 kW (20.1 hp) |
| Wheel Mount | HSK-E50 |
| Linear Axes | X, Y, Z |
| Rotary Axes | A, C (5-axis simultaneous) |
| Positioning Accuracy | < 0.003 mm (< 3 µm) |
| Automatic Wheel Changer | Yes (multi-pack) |
| Coolant System | High-pressure grinding coolant, filtration |
| CNC Control | Siemens Sinumerik 840D sl / NUMROTO |
| Manufacturer | ORTEC |
| Model | GMX 400 LINEAR |
| Year | 2004 |
| Condition | Used |
| Stock Number | 064378 |
| Status | Available |
| Number Of Axis | 5-Axis |
| Tool Changer | 60 ATC |
| Cnc Control | SIEMENS 840D |
| Spindle | 12,000 rpm |
| Spindle Taper | HSK-A63 |
| B Axis | +/- 120 degrees |
| Spindle Number | 2 |
| Turret Number | 1 |
| Spindle 1 | 4,000 rpm |
| Turret 1 | 12 Position |
| Spindle 2 | 4,000 rpm |
| Taper Type | VDI 40 |
| Swing Diameter | 25.2" |
| Max Turning Diameter | 25.2" |
| Max Turning Length | 62.4" |
| Drive Power | 60.3 hp |
| Max Speed | 4,000 rpm |
| Torque | 553.2 lb/ft |
| Torque C Axis | 442.5 lb/ft |
| Chuck Diameter | 7.9-15.7" |
| Chuck Currently On Main Spindle | SCHUNK ROTA THW plus 315-104 |
| Max Bar Diameter | 3.5" |
| Rapid Traverse Speed X Y Z | 1,574/945/2,755 ipm |
| Linear Drive Z1 | 1FN3900-3WB00 |
| Slide Travel X1 Y1 | 21.7"/+/-4.3" |
| Measuring Systems | absolute direct |
| Tool Mount | HSK63-A |
| Max Spindle Speed | 12,000 rpm |
| Max Drive Power | 29.5 hp |
| Max Torque | 553.2 lb/ft |
| Indexing Of Spindle Axis | 1 Degrees |
| Swivel Travel B1 | Plus or minus 120 degrees |
| Resolution | 0.001 Degrees |
| Hydraulic Clamping | 1,475 lb/ft |
| Number Of Tool Stations | Shelf 60 |
| Length Max Number | 7.9/1.5-13.8/29.5 |
| Tool Weight G1 G2 | 6/10 lbs |
| Tool Diameter Max With Pocket Empty | 80-140" |
| Tool Exchange Time G1 G2 | 1.3/2.6 s |
| Type Of Tool Exchange | covered |
| Average Chip To Chip Time | 8 s |
| Volume | 264.2 gal. |
| Belt Filter Filter Fineness | 40 um |
| Pres Pump 1 Pump 2 Pump 3 With Cool Device | 8/20/80 bar |
| Shaft Diameter According To Vdi Din 69880 | 1.6" |
| Max Power | 15.7 hp |
| Rapid Traverse Speed X Z | 945/1,574 ipm |
| Slide Travel X2 Z2 | 225/1,400" |
| Rapid Traverse Speed Z | 1,417 ipm |
| Feed Power S6 40 Dc | 13 kN |
| Slide Travel Z3 | 59.1" |
| Setup Dimensions L H B | 366.1"/181.1"/120.1" |
| Gross Weight Including Cnc | 44,000 lbs. |
| Processor Interface | Pentium III 1,2 GHz |
| Screen | 15"-TFT Screen |
| Power Requirement | 88 kW |
Specifications sourced from machinio.com — verified 2026-03-28
Strengths & Limitations
Strengths
- Full 5-axis simultaneous grinding enables complex flute geometries, relief angles, and chip breaker forms in a single setup without re-fixturing
- Integrated automatic wheel changer and dressing system maintains wheel profile accuracy throughout production runs without operator intervention
- NUMROTO software compatibility provides a library of standard tool geometries, reducing programming time dramatically for common end mills, drills, and reamers
- Sub-3-micron positioning accuracy on all axes delivers the geometric precision that premium solid carbide cutting tool production requires
Limitations
- Acquisition cost of $350,000-$550,000 is only justifiable for shops with high-volume tool production or reconditioning operations
- Tool grinding expertise is a specialized skill set; operators require significant training time compared to general machining center operators
- Limited to 400mm tool length — longer specialty tools (gundrills, long-reach end mills over 400mm) require a larger machine class
Best For
Frequently Asked Questions
01
The GMX 400 handles the full range of rotary cutting tools: end mills (2-flute through 8-flute), drills (twist, carbide, step), reamers, countersinks, taps (for thread grinding), burrs, hobs (smaller diameter), and custom form tools. The 5-axis simultaneous capability covers helix grinding, relief grinding, gashing, and chip breaker forming in a single setup.
02
NUMROTO is an optional software package from NUM that runs as the CAM/NC environment for tool grinding on compatible machines. On DMG Mori tool grinding machines, NUMROTO or an equivalent tool grinding software (such as Walter Helitronic Tool Studio or a Siemens-based system) is typically quoted as an option. It is highly recommended for shops that need to program a variety of tool geometries — the geometry library alone reduces setup time by 60-80% compared to manual programming.
03
The machine uses HSK-E50 wheel arbors as standard. Compatible wheel materials include CBN (cubic boron nitride) for HSS and cobalt tool grinding and diamond wheels for solid carbide tools. Standard wheel packs for common operations (cylindrical OD, end grinding, fluting, relief) are available from major wheel manufacturers including Saint-Gobain, 3M, and Tyrolit.
04
Yes. The GMX 400 is compatible with automated loading systems — robot arms and gravity-feed magazine loaders are both used in production tool grinding environments. Combined with the automatic wheel changer and dressing system, it can operate for multiple hours without manual intervention on standard tool families. Batch sizes of 50-200 tools overnight are achievable on common geometries.
05
Walter Helitronic (now United Grinding) and Rollomatic are the primary competitors in the 5-axis tool grinding segment. Both have strong reputations: Helitronic is widely used in European tool manufacturing; Rollomatic has a strong following in North America for carbide round tool production. DMG Mori's GMX series competes on the strength of its CELOS ecosystem integration and DMG Mori's broad global service network. Shops already standardized on DMG Mori cutting centers often prefer the GMX for consistency in service contracts and operator familiarity.
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