Axis Structure: What Do 3, 4 and 5 Axes Mean?
On a CNC machine the word "axis" denotes the number of independent directions in which the machine head can move in space.
- X — horizontal travel along the bridge (usually 3,000-6,000 mm)
- Y — cross travel beneath the bridge (1,500-3,000 mm)
- Z — up and down plunge (300-500 mm)
- C — head rotation, 0-360° (changes the cutting direction, the "yaw")
- A — tilt axis, ±90° (the "tilt" used for chamfering, V-cut and 3D machining)
4 Axis (X, Y, Z + C or A)
- Straight cutting + one rotation or one tilt
- Sufficient for standard marble cutting
- Side cutting (cladding) can be done
- Lower investment cost
- 3D sculpting and complex contours CANNOT be done
5 Axis (X, Y, Z + A + C)
- Both rotation and tilt — full 3D movement
- V-cut (45° chamfer), internal corner profile
- Kitchen countertop edge rounding (ogee, bullnose)
- Sculpting work, decorative relief
- Complex internal cut-out + edge profile in a single setup
- Higher investment, far broader capacity
Why Is the Bridge Type Structure Preferred?
On bridge type (gantry) machines the head travels in the X axis on a bridge spanning above the material. The advantages:
- Large working area — slabs of over 6,000 × 2,000 mm can be machined in one go
- High rigidity — a twin-column bridge plus a solid horizontal beam; vibration is minimal
- The material stays put — the stone does not move, which is critical for accuracy
- Industry standard — every workshop processing large marble or granite slabs uses this structure
Spindle Technology
The spindle is the motor plus tool holder unit that does the cutting and machining. On CNC bridge machines:
- Power: 9-15 kW (for marble and granite), 18-30 kW (3D machining + heavy work)
- Speed: 2,000-4,000 rpm (diamond blade) / 6,000-24,000 rpm (3D milling tool)
- Cooling: oil circulation unit — the temperature is held between 25-45°C
- Tool taper: ISO30, ISO40 or HSK63 (for fast tool changes)
- Lubrication: central automatic lubrication system — operator intervention is minimal
Typical Applications
- Kitchen countertop cutting + edge rounding + sink cut-out
- Bathroom panel + internal corner + chamfer + decorative relief
- Marble flooring — bespoke sizes, bespoke patterns
- Sculpture and works of art (3D machining)
- Gravestones — shape + lettering + decorative relief in a single setup
- Façade panels — bespoke patterns, laser-marked composite
- Architectural elements requiring tight tolerances (columns, column capitals)
Accuracy and Quality
Modern 5 axis machines offer ±0.05 mm repeatability. That level is maintained by annual laser interferometer calibration. Cut quality depends on the spindle speed, the feed rate, the tool type and the cooling water flow being set correctly.
CNC Software (CAM)
The design file (DXF, DWG, STL) is processed in CAM software and sent to the machine as G-code. Common software: TEX Computer (the USEL standard), Fagor optional. The operator receives programming training on the five-day operator course that USEL Academy runs specifically for our machines.
Operational Characteristics
5 axis CNC bridge machines are an efficient solution for medium to high volume workshops thanks to their capacity and productivity advantages. The operational input items are: electricity consumption, cooling water, central lubrication, diamond blade or milling tool depreciation, and periodic spindle servicing. The net running cost varies with production volume, material type and local input prices.
Which USEL Model Is Right for You?
- 4 Axis CNC Bridge Saw and Machining — Standard marble cutting, straight work + manual chamfering; for workshops with a controlled investment budget
- 5 Axis CNC Bridge Saw and Machining (STORMA) — General cutting + 3D chamfering + V-cut
- 5 Axis 3D CNC Marble Machining Centre — High-volume 3D machining + sculpting + advanced series production