Why a Waterjet for Glass Cutting?
- COLD CUTTING — no thermal shock, minimal risk of cracking
- COMPLEX SHAPES — internal holes, organic contours, mosaic
- THICKNESS — float glass up to 50 mm, laminated up to 60 mm
- PRECISE DETAIL — ±0.1 mm tolerance, fine lettering and logos
- EDGE QUALITY — matt, and can be cleaned up with further polishing
- LAMINATED GLASS — cuts through the interlayer (PVB) without trouble
Which Types of Glass Can Be Cut?
| Glass Type | Max. Thickness | Notes |
|---|---|---|
| Float glass | 50 mm | Standard, the most common |
| Laminated glass (PVB interlayer) | 60 mm | Cuts the PVB without trouble; automotive/safety |
| Mirror glass | 25 mm | Delicate work; the coating is preserved |
| Acrylic (PMMA, plastic) | 100 mm | Pure waterjet or low garnet |
| Stained glass | 15 mm | Coloured, decorative work |
| Glass-ceramic composite | 30 mm | Aerospace sector |
| Quartz glass (silica) | 40 mm | Resistant to high temperatures |
TEMPERED GLASS — CANNOT BE CUT
Tempered (toughened) glass CANNOT BE CUT — internal stress makes it shatter under shock at the cutting point. Tempering is carried out AFTER the glass has been cut. The order cannot be reversed.
Crack Prevention — Critical Strategies
- SLOW PIERCE — entry at low pressure (low-pressure pierce mode)
- PIERCE UNDER WATER — an extra layer of water at the pierce point (the splash is softened)
- SUPPORT UNDER THE GLASS — minimum vibration during cutting (a rubber mat or foam)
- MODERATE CUTTING SPEED — cutting too fast brings a risk of thermal shock
- BALANCED GARNET QUANTITY — too little → an incomplete cut, far too much → cracking
- EDGE FINISHING — the edge comes out matt after cutting and is brought to a gloss by polishing
Pierce Technique — Specific to Glass
The standard pierce method (straight in at high pressure) is risky for glass. Modern waterjet machines offer a "low pressure pierce" mode:
- Stage 1: a gentle entry at low pressure (1,000-1,500 bar)
- Stage 2: the garnet feed is increased slowly
- Stage 3: a slow transition to full pressure (4,000-6,000 bar)
- Total pierce time: 8-15 seconds (for glass)
- On standard metal 1-2 seconds is enough — glass is far more delicate
Types of Application
Architectural Glass
- Façade panels — bespoke sizes plus a decorative pattern
- Partition walls (offices, banks, hotels) — an integrated logo
- Balustrades and balcony glass — thick multi-layer laminate
- Roof glazing and skylights
- Shopfronts (the front glass of a store) — bespoke contours
Decorative Glass
- Lighting fittings — bespoke shapes
- Glass furniture parts (shelf, door, table)
- Stained glass panels — small-piece mosaic
- Works of art — modern illuminated panels
- Shop decoration — lettering and logos
Industrial Glass
- Optical glass — contours to a defined tolerance
- Solar panel glass — cutting plus half-cut/scoring
- LCD/LED screen frame glass
- Filter glass — bespoke shapes
- Laboratory equipment glass
Edge Finishing
- THE EDGE AFTER CUTTING — matt (the Q3-Q4 class)
- POLISHING MACHINE — a semi-gloss (matt/satin) finish
- WET POLISHING — a full mirror gloss
- EDGE ROUNDING — for safety (no sharp edges)
- CHAMFER CUTTING — a straight angled edge with a 5-axis waterjet
- V-CUT — a 45° angle at the corner (for thick multi-layer laminate)
Quality Control After Glass Cutting
- Micro-crack inspection — the edge under a magnifier
- Optical distortion — no distortion in the reflection of flat glass
- Contour dimensions — ±0.1 mm tolerance
- Surface cleanliness — no garnet residue
- Edge roughness — conformity to the Q standard
- Architectural glass: heat resistance and optical quality tests (where required)
Common Problems and Solutions
| Problem | Cause | Solution |
|---|---|---|
| A pierce crack | Going straight in at high pressure | Use a low-pressure pierce |
| Micro-cracking at the edge | Fast cutting, excess vibration | Reduce the speed by 20%, add support underneath |
| A wavy side face | Thick glass, the taper effect | Go slower, or use 5-axis tilt compensation |
| Garnet staining at the edge | Inadequate cleaning | Ultrasonic cleaning afterwards |
| Damage to a mirror glass coating | Garnet splash | Protective film, the coated side face down |