Comparison · Waterjet vs laser
Short answer: sometimes, with the right laser and a lot of care — and sometimes not well at all. Reflective metals are one of the clearest places a laser meets its limits, because the very property that makes them valuable, their reflectivity, is exactly what fights the beam. If your work involves copper, brass or precious metals, it's worth understanding why — and what the alternative is.
Why reflective metals fight the laser
A laser cuts by getting the material to absorb its energy and heat up until it melts. Reflective metals do the opposite of what the process needs:
- They reflect the beam. At the ~1 µm wavelength of a fibre laser, copper, gold and silver absorb only a small fraction of the incident energy and bounce the rest away, so much more power is needed to start and sustain a cut.
- They conduct heat away. High thermal conductivity pulls heat out of the cut zone faster than the beam delivers it, making the process slow and unstable.
- They can reflect energy back into the machine. Back-reflection is a genuine risk to the laser source on highly reflective stock, and a reason some setups simply won't cut it.
High-brightness fibre lasers have improved this considerably, and copper can be cut — but it remains a demanding, slower, less forgiving case than ordinary mild steel.
Where this shows up
- Copper and brass — electronics, connectors, busbars, RF and thermal-management components, where precise, clean cuts in conductive metal are routine.
- Gold, silver and platinum — jewellery, fine accessories and precious-metal work, where every gram and every edge counts, and where reflectivity and value compound the problem.
- Aluminium — manageable for many lasers, but reflectivity and heat conduction still affect speed and edge quality.
Why micro abrasive waterjet doesn't care
Micro abrasive waterjet doesn't ask the material to absorb light — it removes material by mechanical erosion, a fine abrasive jet wearing the contour cold. That makes reflectivity, thermal conductivity and melting point irrelevant: copper cuts much like steel cuts much like brass. There's no back-reflection risk, no heat distortion and no discolouration, and the edge is cold and burr-free. Two further advantages matter on high-value metals specifically: the kerf is fine, so material loss is minimal — which counts when the material itself is the cost — and the part comes off with its properties unchanged.
When it matters most
If your work involves reflective or precious metals — copper and brass in electronics, or the fine-metal components common in luxury and jewellery — a non-thermal process removes the reflectivity problem entirely, and removes the secondary clean-up with it.
Send us the part and the material and we'll cut a sample: book a test cut. The full process comparison is in our waterjet vs laser comparison.
Frequently asked questions
Can a fibre laser cut copper?
A high-brightness fibre laser can cut copper, but it's slower and more demanding than non-reflective metals, with edge-quality and machine-safety (back-reflection) considerations.
Why are reflective metals hard to laser cut?
They reflect much of the beam instead of absorbing it, and conduct heat away quickly, so the process needs more power and is slower and less stable.
What's the best way to cut copper and brass precisely?
A non-thermal process such as micro abrasive waterjet, which ignores reflectivity and conductivity and produces a cold, burr-free edge.
Can waterjet cut gold and other precious metals?
Yes — and with a fine kerf, so very little of the material is lost in the cut, which matters when the metal is the cost.