How to Engrave Metal With a Fiber Laser: Settings and Speed Guide
Fiber laser settings for metal work aren't one-size-fits-all. Stainless steel, aluminum, brass, and titanium each respond differently to laser energy, and even within a single material category the surface finish — polished, brushed, anodized, powder-coated — changes how you need to approach the parameters. The good news is that once you understand why each variable matters, the adjustments become intuitive rather than guesswork.
This guide covers the four core parameters, then works through each major metal with practical starting settings, what to expect, and what to watch out for.
If you're still working on getting your machine physically set up and connected, start with our guide to how to set up a fiber laser engraver before diving into material-specific settings.
What Determines the Quality of a Metal Engraving
Every metal engraving result is determined by four parameters working together. Understanding what each one does prevents the most common frustrations.
Power (%) — determines how much energy the laser source delivers per unit time. Higher power removes more material more aggressively. More is not always better: too much power causes burning, discoloration, and surface damage. Most standard marking on metal runs between 40–80% on a 20–30W machine.
Speed (mm/s) — how fast the galvo mirrors move the beam across the surface. Faster speed means less time on each point, less energy per unit area, lighter marks. Slower speed means more energy delivered, deeper or darker marks. Speed and power work inversely: if you increase one, you typically need to compensate with the other to hold the same mark depth.
Frequency (kHz) — how many laser pulses fire per second. Lower frequency (20–50kHz) delivers fewer, more powerful individual pulses — better for aggressive ablation and deep marks. Higher frequency (50–200kHz+) delivers more pulses per second at lower peak power each — better for smooth surface marks, annealing, and color work. Frequency changes the texture and character of the mark more than just its depth.
Pulse width (ns) — only adjustable on MOPA lasers. Controls the duration of each individual pulse. Short pulses (2–30ns) deliver very high peak power briefly, creating thin oxide layers for color effects. Long pulses (100–500ns) deliver energy over a longer period, better for deep ablation and annealing. On a standard Q-switched fiber laser, pulse width is fixed at approximately 120ns. On a MOPA, it's the key variable for color work and fine surface control. Our MOPA vs standard fiber laser guide covers this distinction if you want to understand the technical difference.
Hatch spacing — the distance between parallel fill lines. Tighter spacing (0.03–0.05mm) produces more uniform fills and is slower. Wider spacing (0.06–0.1mm) is faster but can look lined if too wide for your application. For most solid fill marks, 0.05mm is a safe default.
One principle that applies to every material: always run a test grid before engraving production pieces. Design a matrix of small squares — vary power across one axis, speed across the other — and engrave it on scrap of the same material. Photograph the results, label each square, and keep the grid as your reference. This single practice prevents more wasted material than anything else.
Stainless Steel: The Most Common Starting Point
Stainless steel (grades 304 and 316 are most common) is the go-to starting material for fiber laser calibration. It responds predictably, shows clear marks at a wide range of settings, and is the metal most buyers use fiber lasers for.
Recommended Settings Range
For a 20W fiber laser with a 110mm lens on clean 304/316 stainless steel:
| Application | Power | Speed | Frequency | Passes | Hatch |
|---|---|---|---|---|---|
| High-contrast surface mark | 50–65% | 600–1,000 mm/s | 30–50kHz | 1–2 | 0.05mm |
| Deep engraving | 70–85% | 300–500 mm/s | 20–35kHz | 3–5 | 0.04mm |
| Black annealing (MOPA) | 60–75% | 400–700 mm/s | 25–45kHz | 1–2 | 0.04mm |
For 30W machines, reduce starting power by 10–15% across the board — the higher wattage delivers more energy per unit area at equivalent percentage settings. For 50W machines, reduce by 20–25%.
Always clean stainless with isopropyl alcohol (90%+) before engraving. Fingerprint oils, manufacturing oils, and residues from packaging all affect how the surface oxidizes, which changes both the mark appearance and consistency.
Deep Engraving vs Surface Marking
Surface marking — the most common application — creates a visible, high-contrast mark by changing the surface layer through ablation or oxidation. The mark depth is measured in micrometers and is not tactile on most settings. For logos, text, serial numbers, and decorative designs, this is what you want.
Deep engraving removes significant material depth — measurable in tenths of millimeters — and creates a tactile recessed mark. It's used for mold texturing, tool marking, nameplate recesses, and applications where the mark needs to survive heavy abrasion. Deep engraving requires multiple passes (3–10+ depending on depth), lower speed, and moderate power to avoid heat buildup that warps thin material. Allow brief cooling between passes on thin sheet — 10–15 seconds between passes prevents thermal distortion.
Achieving High-Contrast Black Marks
The most requested result on stainless steel is a deep, clean black mark — sharp logo or text in high contrast against the silver surface. Two routes achieve this:
Standard ablation black: moderate power (50–65%), moderate-low speed (500–800mm/s), frequency 30–50kHz. The laser removes the surface layer and the exposed metal oxidizes dark. Results depend on surface finish — brushed stainless produces a different black tone than polished.
MOPA black annealing: on a MOPA laser, you can produce a particularly rich, smooth black through annealing — heating the surface enough to form a stable dark oxide layer without removing material. Settings: pulse width 100–200ns, frequency 20–45kHz, power 60–75%, speed 400–700mm/s. The annealed black is often preferred for premium product branding because it's more uniform and has less surface texture variation than ablation. For a full treatment of MOPA-specific settings including color, see our fiber laser color engraving guide.
Aluminum and Anodized Aluminum
Aluminum is a significantly different material from stainless steel — softer, higher thermal conductivity, and reflective. The settings that work for stainless will not work directly on aluminum.
Raw Aluminum Settings
Raw (bare) aluminum reflects a large percentage of the 1064nm fiber laser wavelength, which means more of the laser energy bounces off rather than being absorbed. You need higher power than you might expect to get a clean mark.
For 20W fiber laser on raw aluminum (brushed or satin finish):
| Application | Power | Speed | Frequency | Passes |
|---|---|---|---|---|
| Surface marking | 65–80% | 400–700 mm/s | 25–45kHz | 1–2 |
| Deep engraving | 80–90% | 200–400 mm/s | 20–35kHz | 3–6 |
Mirror-polished aluminum is the most challenging — the high reflectivity increases back-reflection risk and makes consistent marks harder to achieve. Either apply a thin coat of laser marking spray (Cermark or equivalent) for a coated surface to interact with, or work with satin/brushed finishes where practical.
The mark on bare aluminum is typically light gray to dark gray rather than the near-black you get on stainless. It's visible but lower contrast. For a truly high-contrast black mark on aluminum, anodized aluminum is a much better substrate.
Anodized Aluminum: Different Rules Apply
Anodized aluminum behaves completely differently from bare aluminum because the laser is interacting with the anodized coating rather than the base metal. The anodized layer is essentially a hard oxide film (typically 5–25 micrometers thick) that absorbs 1064nm energy much more efficiently than bare aluminum. The result is a high-contrast mark at much lower power.
For 20W fiber laser on anodized aluminum (black or colored anodized):
| Application | Power | Speed | Frequency | Passes |
|---|---|---|---|---|
| Light-colored mark (white appearance) | 25–40% | 1,000–2,000 mm/s | 50–80kHz | 1 |
| Dark mark | 40–55% | 600–1,000 mm/s | 40–60kHz | 1–2 |
The key with anodized aluminum is to remove the anodized layer to reveal the lighter aluminum below (for a white/light mark on dark anodized) or to ablate the surface differently for contrast on lighter anodized finishes. The mark is permanent because it's the base metal being revealed, not just a surface color change.
Start conservatively on anodized aluminum — it's more sensitive to over-engraving than bare metal, and burning through the anodize layer into the metal below changes the appearance completely. Low power, high speed, single pass is your starting approach.
Brass and Copper
Brass and copper are popular substrates for decorative engraving, jewelry, and instrument parts — but they present challenges that catch beginners off guard.
Settings and What to Expect
Both metals have higher thermal conductivity than stainless steel, meaning heat dissipates quickly into the bulk of the material rather than concentrating at the surface. This requires more power to compensate.
For 20W fiber laser on brass (yellow brass, common alloy):
| Application | Power | Speed | Frequency |
|---|---|---|---|
| Surface marking | 70–85% | 400–700 mm/s | 25–45kHz |
| Deep engraving | 80–90% | 200–350 mm/s | 20–30kHz |
Copper requires slightly higher power still — it's one of the most thermally conductive common metals and also one of the most reflective at 1064nm. Expect to use 80–90% power for surface marking. The mark on copper is typically a darker tone against the copper surface — high contrast if settings are right, but surface discoloration (heat-affected zone around the mark) is common if power is too high or speed too slow.
For a beginner-friendly comparison of how fiber lasers handle these materials in practice, our ComMarker B4 review includes hands-on testing on brass and copper alongside stainless.
Managing Reflectivity
Reflectivity is the main practical concern with brass and copper. Polished brass and copper can send a meaningful percentage of the laser energy back toward the lens. Over time, this contributes to lens degradation and potentially to laser source damage.
Practical mitigations: work with satin or brushed finishes where possible, apply a thin coat of laser marking spray on highly polished pieces, and monitor your lens condition more frequently when regularly engraving copper. The field lens is the component most exposed to back-reflection — keep it clean and inspect it for coating damage periodically.
Gold and silver behave similarly to copper in terms of reflectivity, require high power settings, and benefit from the same surface prep approaches.
Titanium
Titanium is a favorite material for premium applications — knife scales, watch components, jewelry, medical devices, and high-end drinkware. It's harder than stainless steel, has lower thermal conductivity (which actually helps laser interaction), and produces remarkable color effects on MOPA lasers.
Settings for Marking and Color Effects
For standard surface marking, titanium settings are broadly similar to stainless steel — start around the same parameters and adjust based on results.
For 20W fiber laser on titanium (grade 2 or grade 5):
| Application | Power | Speed | Frequency |
|---|---|---|---|
| High-contrast marking | 55–70% | 500–800 mm/s | 30–50kHz |
| Deep engraving | 70–85% | 300–500 mm/s | 20–35kHz |
Where titanium genuinely distinguishes itself is color marking on MOPA lasers. Titanium's oxide layer (titanium dioxide, TiO₂) has a higher refractive index than the chromium oxide layer on stainless steel, which amplifies the thin-film interference effect significantly. The colors produced on titanium — particularly blues, golds, and purples — are noticeably more vivid and saturated than equivalent marks on stainless.
For MOPA color on titanium, use similar frequency and pulse width ranges as stainless steel but expect to find your color sweet spots at slightly different power/speed combinations. Build a separate test grid for titanium — don't assume your stainless parameters transfer directly. The higher refractive contrast means colors shift at different oxide thicknesses, so the parameters that produce gold on stainless may produce a different tone on titanium.
Common Problems and Solutions
Marks Too Light or Inconsistent
Most likely cause: Power too low, speed too high, or incorrect focus.
Start by verifying focus — even 1–2mm off focus reduces energy density enough to produce faint marks. Re-calibrate using your machine's focus method (two-dot convergence, autofocus, or focus spacer block).
If focus is correct: increase power by 5–10% or reduce speed by 100–200mm/s. Add a second pass before aggressively increasing power — two passes at moderate settings often produces better results than one pass at high power.
For inconsistency across a batch: surface contamination is the most common cause. If some pieces mark well and others don't, the variable is almost always surface condition. Clean every piece consistently.
Surface Damage or Burning
Most likely cause: Power too high, speed too slow, or frequency too low for the application.
Burning (visible heat-affected zone around the mark, discoloration of the surrounding metal) indicates too much total energy. Reduce power by 5–10% first. If burning persists, increase speed or raise frequency — higher frequency delivers energy more evenly with lower peak pulses, which reduces thermal impact.
For thin material (under 0.5mm): always use multiple lighter passes rather than attempting the target depth in one high-power pass. Thin sheet has almost no thermal mass to absorb excess energy.
Blurry Edges
Most likely cause: Focus error, incorrect correction file loaded, or mechanical vibration.
Verify focus first — blurry edges are most commonly a focal distance problem. If focus is confirmed correct: check that the correct .cor correction file for your installed lens is loaded in EZCAD2 or LightBurn. The wrong correction file causes geometric distortion that appears as blurring, especially at the edges of the work area.
If both are confirmed correct: check that the material is flat and fully supported, and that the machine isn't being vibrated by external sources (HVAC, nearby equipment). Even subtle vibration causes visible edge degradation at high galvo speeds.
How Material Finish Affects Results
Surface finish is often overlooked in settings guides but has a significant effect on mark appearance — sometimes more than small parameter adjustments.
Mirror-polished finish produces the most visually striking marks on stainless steel and titanium. The high reflectivity of the surrounding surface maximizes the contrast between the mark and the base material. For color engraving specifically, polished surfaces produce the most vivid, saturated colors because the thin-film interference effect is maximized by the reflective background. The trade-off: polished surfaces show fingerprints and handling marks more than brushed finishes, which means consistent glove handling is required throughout the process.
Brushed/satin finish produces softer, slightly lower contrast marks than polished — the directional surface texture diffuses reflected light. For most functional marking (logos, text, serial numbers) the contrast is still completely professional. Many customers actually prefer the look of laser marks on brushed stainless because the surface texture reads as more intentional and less stark. Color marks on brushed stainless are softer and more muted than on polished — again, can be desirable depending on the aesthetic.
Bead-blasted/matte finish produces the lowest contrast and least vivid colors. The random surface texture scatters all reflected light diffusely. For high-contrast functional marking on matte surfaces, higher power and more passes help compensate. For color work, matte finishes are generally not recommended as a substrate.
Powder-coated and painted surfaces: the laser removes the coating rather than interacting with the base metal. This requires significantly less power than marking bare metal — start at 30–40% power for powder coat removal. The mark reveals the base metal underneath, which creates a two-tone contrast between the coating color and the metal. Common for branded promotional products, tool handles, and industrial components.
Final Advice
Metal laser engraving rewards methodical testing and disciplined documentation more than any other laser application. The variables interact in ways that aren't always predictable from theory — your machine, your specific metal stock, your lens, and your ambient conditions all introduce small differences from published reference settings.
Build your own settings library from the ground up. The test grid process — running a systematic power/speed matrix on scrap of each new material — takes 15–20 minutes and produces a reference that saves hours over the life of your machine. Document every successful parameter set. When a customer orders 200 branded steel tags three months from now, you'll want to reproduce that perfect mark without any guesswork.
A few principles that hold across every material:
Clean surfaces are non-negotiable. IPA clean, nitrile gloves, every time. This matters more than most parameter adjustments.
Match your approach to the application. Deep engraving and surface marking require different strategies — don't try to achieve both with the same settings.
More passes at moderate power beats one pass at maximum power for almost every application on metal. It's more forgiving, produces less heat distortion, and gives you more control over depth.
If you're moving toward color work on stainless steel or titanium — one of the highest-value applications for a fiber laser — you'll need a MOPA laser and a solid understanding of pulse width and frequency. Our guide to fiber laser color engraving covers the MOPA-specific methodology in full.
Frequently Asked Questions
What are the best settings for laser engraving stainless steel?
For a 20W fiber laser with a 110mm lens on clean 304/316 stainless steel, solid starting settings for high-contrast surface marking are: power 50–65%, speed 600–1,000 mm/s, frequency 30–50kHz, 1–2 passes, 0.05mm hatch spacing. For deep engraving, increase power to 70–85%, reduce speed to 300–500mm/s, frequency 20–35kHz, and use 3–5 passes with brief cooling between them. Always run a power/speed test grid on scrap stainless before engraving production pieces, as every machine and metal batch varies slightly.
Why are my fiber laser marks on aluminum so light?
Bare aluminum reflects a large percentage of 1064nm fiber laser energy, meaning less energy is absorbed by the surface compared to stainless steel. You typically need significantly higher power (65–80%+) than for stainless at equivalent settings. Also verify your focus is correct — aluminum is particularly sensitive to focus errors. If you need high-contrast black marks on aluminum, anodized aluminum is a better substrate — it requires much less power (25–55%) and produces higher contrast because the laser interacts with the anodized coating rather than the reflective base metal.
What's the difference between anodized aluminum and raw aluminum settings?
The laser interacts with these two materials completely differently. On raw aluminum, the beam ablates the metal surface directly, requiring high power (65–80%+) to overcome the metal's reflectivity and thermal conductivity. On anodized aluminum, the beam removes or modifies the anodized coating (not the base metal), which absorbs laser energy much more efficiently. This requires significantly less power — typically 25–55% on a 20W laser — and produces high-contrast marks. Use much lower power on anodized aluminum than raw aluminum, and start conservatively to avoid burning through the anodize into the metal below.
Can you engrave brass with a standard fiber laser?
Yes, brass engraves well with a standard fiber laser but requires higher power than stainless steel due to its high thermal conductivity and reflectivity. Starting settings for brass on a 20W fiber laser: power 70–85%, speed 400–700mm/s, frequency 25–45kHz. Copper requires even higher power and is particularly reflective at 1064nm — work with brushed or satin finishes where possible rather than mirror-polished, and be aware of back-reflection risk with polished copper or brass. Clean the surface thoroughly before engraving.
Does material finish affect laser engraving results?
Significantly. Polished/mirror surfaces produce the highest contrast marks and most vivid color effects because the surrounding reflective surface maximizes visual contrast. Brushed/satin finishes produce softer, slightly lower contrast marks that many prefer for a less stark industrial appearance. Matte/bead-blasted surfaces produce the lowest contrast. For color marking specifically, polished stainless or titanium is strongly recommended — the reflective background amplifies the thin-film interference effect that produces the colors. On matte surfaces, color work produces noticeably less vivid results at equivalent parameters.
What causes blurry edges in fiber laser engraving?
The three most common causes are: incorrect focal distance (the most frequent — even 1–2mm off focus significantly degrades edge sharpness), incorrect or missing correction file in the software (the .cor file compensates for lens distortion; using the wrong one or not loading one causes geometric distortion that appears as blurring), and mechanical vibration during engraving (ensure the machine is on a stable surface with no external vibration sources). Check focus first, then verify your correction file matches your installed lens. If both are confirmed correct, inspect your work surface for stability issues.
What is the difference between surface marking and deep engraving on metal?
Surface marking creates a visible, high-contrast mark by changing the surface layer through ablation or oxidation at depths measured in micrometers. The mark isn't tactile — it's a visual effect. It's used for logos, branding, serial numbers, and decorative work. Deep engraving removes significant material depth (measured in tenths of millimeters), creating a tactile recessed mark. It requires multiple passes, lower speed, and careful heat management to avoid warping. Deep engraving is appropriate for mold texturing, tool marking, plaques where the mark needs to survive abrasion, and industrial identification that must remain legible under wear.
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