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Optimize Laser Cut Quality
Optimizing Fiber Laser Cut Quality
A Guide for Clients & Operators — 15 mm Carbon Steel & 8 mm Stainless Steel
This comprehensive guide will teach you how to achieve optimal cut quality by understanding and controlling the three critical parameters that determine laser cutting success.
Scenario & Setting
Scenario:
Understanding how Focus, Gas Pressure, and Nozzle Height affect cut quality.
Setting:
Cutting 15 mm carbon steel and 8 mm stainless steel.
Even with correct power and speed, issues like burrs, slag, or uneven texture may appear.
The Big Three
Focus Position
Critical for beam concentration and penetration depth
Gas Pressure
Essential for molten material removal and cut quality
Nozzle Height (standoff)
Determines gas flow coherence and cutting efficiency
Carbon Steel: Focus vs. Slag
Test Parameters
  • Constants: Height 0.6 mm, Air 0.5 MPa
  • Focus series: +13 → +12 → +11 → +10 (from high to low)

Insight: Best focus window is around +11 ~ +12. Too high causes heavy dross; too low increases bottom slag.
Stainless Steel: Focus vs. Burrs (8 mm)
Focus Test Results
Focus series: −4, −5, −6, −7, −11
Insight: Middle values produce fewer burrs; very negative (−11) worsens finish.
Gas Pressure Sweep (Increased) — Carbon Steel
Test Parameters
  • Constants: Height 0.6 mm, Focus +14
  • Pressures: 0.5 → 0.6 → 0.8 → 1.0 MPa

Insight: Optimal around 0.8 MPa; 1.0 MPa may introduce turbulence.
Gas Pressure Sweep (Reduced) — Carbon Steel
Low Pressure Test
  • Constants: Height 0.6 mm, Focus +14
  • Pressures: 0.5 → 0.4 → 0.35 → 0.3 MPa
Insight: Below 0.5 MPa quality drops rapidly; molten metal not fully ejected.
Nozzle Height (Standoff) — Carbon Steel
01
0.3 mm Height
Too close - risk of spatter and nozzle damage
02
0.8 mm Height
Optimal - best gas coherence and cut quality
03
1.0 mm Height
Too far - weak gas jet and poor material removal
Constants: Air 0.5 MPa, Focus +14
Heights: 0.3 ↓, 0.8 ↑, 1.0 ↑
Insight: 0.8 mm standoff offers best gas coherence; 0.3 mm too close (risk of spatter), 1.0 mm too far (weak jet).
Annotated Focus Change (15 mm Carbon Steel)
Focus Impact Analysis
Description: Focus changes from high to low — top focus too high leads to stuck slag ("Difficult to remove"); lower focus improves discharge ("Easy to remove") but surface smoothness must be balanced.
Troubleshooting Matrix
Best Practices (Checklist)
1
Verify nozzle height and sensor calibration
Ensure accurate standoff measurements for consistent results
2
Use clean, dry, high‑purity assist gas
Gas quality directly impacts cut quality and edge finish
3
Adjust one parameter at a time
Systematic approach prevents confusion and enables optimization
4
Record and tag every test result for repeatability
Documentation ensures consistent quality and process improvement
Conclusion & Call to Action
Conclusion:
Perfect cut quality is a precise balance of focus, pressure, and nozzle height.
CTA:
  • Book a live demo
  • Request a quote
Appendix — Image‑to‑Series Mapping (for your reference)