Fiber laser vs. CO2 engraving comes down to one sentence: fiber marks metal, CO2 marks organics. Everything else in this article is detail on top of that sentence, but the detail matters when your project is the one on the table.
Shops that run only one machine will sometimes talk you into the wrong process rather than send you elsewhere. We run both, so we don’t have that incentive.
The difference
The two lasers emit different wavelengths, and materials absorb those wavelengths differently. Fiber sits around 1.06 microns, which metal absorbs well. CO2 sits around 10.6 microns, which wood, leather, glass, and acrylic absorb well. Point a CO2 laser at bare steel and very little happens without a marking spray. Point a fiber laser at a cutting board and you get scorch instead of contrast.
| Fiber laser | CO2 laser | |
|---|---|---|
| Wavelength | ~1.06 microns | ~10.6 microns |
| Best on | Steel, aluminum, titanium, brass | Wood, leather, acrylic, glass |
| Mark types | Anneal, etch, deep engrave | Burn, frosted etch |
| Weak spot | Raw wood, clear organics | Bare metal |
Fiber on metal
Metal absorbs fiber’s wavelength in a way that permits two things CO2 can’t do. Annealing produces a permanent dark mark with zero material removed, which matters for parts that can’t be weakened or given crevices: knife blades, medical items, food-contact pieces. Deep engraving removes metal to a measurable depth, which is what regulatory work demands. The ATF’s firearm marking rules specify a minimum depth of 0.003 inch, and depth like that is a machine setting on fiber, not an aspiration.
Our metal engraving and firearm engraving run on fiber for exactly this reason.
CO2 on organics
Wood develops contrast as the beam caramelizes and chars the grain. Leather darkens sharply. Cast acrylic frosts to a bright white. Glass takes an elegant frosted etch. These are the materials behind our wood, leather, glass, and acrylic work, and CO2 is the right tool for all of them.
Which one you need
You don’t need to know. That’s the shop’s job, and any shop that makes you specify the laser is outsourcing its own expertise to you. Tell us the material and how the item will be used, and we’ll run it on the correct machine with settings matched to the stock.
Not sure what your material even is? That happens more than you’d think, and it’s fine. Request a quote, describe the item, and we’ll sort it out. Reston, VA based, nationwide shipping.
Frequently asked questions
Not well. Wood wants CO2. Fiber on wood produces scorching without much contrast.
Only with a marking spray or a coating, and the result is a surface treatment rather than a true engraving. For real metal marking you want fiber.
Both are permanent. Durability comes from matching the process to the material and the item’s life, not from the laser brand on the machine.