Can a Fiber Laser Engrave Polymer? PMags, Glock Frames, and Grips
Short answer: Yes. A fiber laser can engrave most polymers used on firearms, including PMags, Glock and Sig frames, and many aftermarket grips. The key is controlling heat: polymer melts and bubbles if you hit it like steel. Our standard Edge 50W marking presets for Glock frames, Sig frames, and PMags each run a single pass at 24 to 42% power. Test on a scrap or hidden spot first, and run fume extraction every time. Below are our actual starting presets and how to get clean, consistent marks on the polymer parts gun shops see most.
How a Fiber Laser Marks Polymer
On metal, a fiber laser removes material. On polymer, it mostly changes the surface with heat. Depending on the plastic and your settings, the mark can lighten (the surface foams slightly and turns a frosted gray or white), darken (the surface carbonizes), or cut into the material as an engraved recess.
That's why polymer is less predictable than steel. The base plastic, fillers like glass fiber, and the pigments a manufacturer uses all change how the material reacts. It's also why we keep separate presets for Glock and Sig frames instead of one "polymer" setting: different frames need different numbers.
Our Edge 50W Polymer Presets
These are the starting presets in the LightBurn settings bundle we ship with the Edge 50W, dialed in on the 220mm lens. Each is a single pass with the hatch angle rotating between passes when you add repeats.
| Job | Power | Speed | Frequency | Line interval | Passes |
|---|---|---|---|---|---|
| Glock frame | 42% | 711 mm/s (28 in/s) | 28 kHz | 0.071 mm | 1 |
| Sig frame | 40% | 559 mm/s (22 in/s) | 25 kHz | 0.094 mm | 1 |
| PMag, frosted mark | 24% | 4,826 mm/s (190 in/s) | 35 kHz | 0.089 mm | 1 |
| PMag, photo/image | 60% | 1,016 mm/s (40 in/s) | 25 kHz | 0.033 mm | 1 |
| Cerakote removal on Glock polymer | 50% | 1,143 mm/s (45 in/s) | 28 kHz | 0.071 mm | 1 |
Edge 50W, 220mm lens. Two things stand out. First, polymer settings are dramatically gentler than metal: our PMag frost preset uses 24% power at 190 inches per second. Second, the two frame presets aren't the same, which is the clearest proof that you should dial in each part rather than reuse one number. Treat these as starting points. A different lens changes how concentrated the beam is, so expect to adjust if you run a smaller or larger field, and always confirm on a test spot.
Common Gun Polymers and What to Expect
PMags and other polymer magazines
Polymer magazines are one of the most popular laser jobs: logos, unit markings, names, and numbering for ranges and agencies. Our standard PMag preset produces a frosted, light-gray mark on black, using very low power at very high speed. For photos or detailed artwork, we switch to an image-mode preset with a much finer line interval. Either way, keep heat away from the feed lips and body walls so you don't warp anything that affects feeding.
Glock and Sig polymer frames
Polymer frames are usually a glass-filled nylon. They mark and engrave well with the right settings, and shops use lasers for logos, custom artwork, and texture patterns. Note that our Glock and Sig presets differ in power, speed, frequency, and line interval. Two cautions: stay away from areas that affect function or fit, and remember that on many polymer-frame pistols the serial number sits on an embedded metal plate. For ATF marking rules, see how deep a fiber laser can engrave.
Grips, stocks, and furniture
Aftermarket grips and stocks come in a wide range of plastics and rubber-like materials. Most hard polymers mark well. Softer, rubbery materials are less predictable and tend to melt or leave residue. Always test.
Cerakoted polymer
If a polymer part is Cerakoted, the laser can "blow off" the coating to reveal the polymer underneath, which creates strong contrast. Our preset for this on Glock polymer runs a single pass at 50% power and 45 inches per second: enough to clear the coating without burning into the frame.
Settings That Prevent Melting
- Start low. Begin well below your metal settings and work up. It's easy to add power and impossible to un-melt a frame.
- Go faster. Higher speed spreads the heat out and reduces bubbling. Our PMag preset runs at 190 inches per second.
- One clean pass first. Our polymer presets are single-pass. Get the look you want in one pass before adding repeats, and only add passes if you need a deeper recess, such as for color fill.
- Tune frequency per part. Our polymer presets run between 25 and 35 kHz. Frequency changes how hard each pulse hits, so adjust it alongside power rather than in isolation.
- Run a test grid. Mark a small grid of power and speed combinations on a scrap piece or an out-of-sight area of the same part, then pick the cleanest square.
- Save what works. Once you dial in a brand or part, save it as a preset. That's exactly why our bundle has separate Glock, Sig, and PMag entries.
Getting Better Contrast: Color Fill
Laser marks on black polymer are usually a frosted gray, which can look subtle. For a bolder look, engrave a slightly deeper recess, then color-fill it with paint and wipe off the excess. White, red, and other fill colors make logos and markings pop on magazines and grips, and the recess protects the paint from wear.
Safety: Never Skip Fume Extraction
Lasering plastic produces smoke and fumes you shouldn't breathe, and the residue can coat your lens and the inside of your machine. Run a fume extractor every time you mark polymer. Never laser anything containing PVC or vinyl: it releases chlorine-based gases that are harmful to you and corrosive to the machine. If you can't identify the plastic, don't laser it.
Q-Switched or MOPA for Polymer?
Both can mark polymer. A MOPA's adjustable pulse gives you more control over heat, so it tends to leave cleaner marks on difficult plastics, and it's worth a look if polymer is a large share of your work. A Q-switched laser handles everyday polymer jobs well with the right presets: every setting in the table above runs on our Q-switched Edge 50W. For the full comparison, see MOPA vs Q-switched fiber lasers for gun engraving.
What About a CO2 Laser?
CO2 lasers mark many plastics well, but a gun shop's core work is metal: serial numbers, slides, receivers, and coated parts. A fiber laser handles both metal and most gun polymers, which is why it's the standard choice for firearm work.
Frequently Asked Questions
Can you laser engrave a PMag?
Yes. Our Edge 50W PMag preset (220mm lens) produces a frosted, light-gray mark on black in a single pass at 24% power and 190 inches per second. Keep heat away from the feed lips.
Can you laser engrave a Glock frame?
Yes. Our Edge 50W Glock frame preset (220mm lens) is a single pass at 42% power, 28 inches per second, and 28 kHz. Avoid areas that affect function, and test on a hidden spot first.
Do Glock and Sig frames use the same laser settings?
No. In our presets, the Sig frame runs at 40% power and 22 inches per second versus 42% and 28 inches per second for Glock, with different frequency and line spacing. Dial in each frame separately.
Why does my polymer mark melt or bubble?
Too much heat in one place. Lower the power, increase the speed, and get the mark right in a single pass before adding repeats.
How do I make laser marks on black polymer stand out?
Engrave a shallow recess and color-fill it with paint. The fill adds contrast, and the recess protects it from wear.
Is it safe to laser engrave plastic?
Yes, with fume extraction and the right materials. Never laser PVC or vinyl, and don't laser any plastic you can't identify.
Talk to a Laser Specialist
SA Laser is a veteran-owned company in San Antonio, Texas, selling and supporting fiber and CO2 laser systems since 2012. Every Edge ships with a LightBurn settings bundle that includes presets like these, and our 5-day, in-person Spark training covers real-world settings on metal and polymer so you're producing sellable work from day one. Questions about engraving polymer parts? Book a call or reach us at (888) 964-3568.