The choice between Fiber and CO2 laser cutting comes down to physics: they operate at different wavelengths of light, which fundamentally dictates what materials they can cut and how efficiently they do it.
Here is the definitive comparison to help you decide which technology fits your needs.
⚡ The Fundamental Difference: Wavelength
The most important technical distinction is the wavelength of the laser beam.
- Fiber Laser (1.06 micrometers): Produces a very short wavelength. It is readily absorbed by metals, including reflective ones like copper and brass. However, this wavelength passes straight through most organic materials (wood, plastic) without cutting them.
- CO2 Laser (10.6 micrometers): Produces a wavelength 10x longer. It is highly absorbed by organic materials and glass. It generally reflects off bare metal unless the metal is coated or the laser power is extremely high.
⚔️ Side-by-Side Comparison
| Feature | Fiber Laser | CO2 Laser |
|---|---|---|
| Best Materials | Metals (Steel, Aluminum, Brass, Copper, Titanium). | Non-Metals (Wood, Acrylic, Leather, Fabric) & some Metals. |
| Cutting Speed | Extremely Fast on thin metals (up to 3-5x faster than CO2). | Slower on thin metals; competitive on very thick plate (20mm+). |
| Maintenance | Near Zero. Solid-state source. No moving mirrors to align. | High. Requires mirror alignment, lens cleaning, and gas resonator maintenance. |
| Operating Cost | Low. High electrical efficiency (~30-40% wall-plug efficiency). | High. Low electrical efficiency (~10%). Consumes laser gas. |
| Reflective Metals | Excellent. Cuts copper/brass easily. | Dangerous. Reflections can damage the machine optics. |
| Safety | High Risk. Light damages retinas instantly; requires fully enclosed cabin. | Moderate Risk. Standard polycarbonate (clear plastic) blocks the beam. |
🪵 vs ⚙️ Detailed Material Breakdown
1. When to choose Fiber (Metal Fabrication)
Fiber has completely dominated the metal fabrication industry.
- Thin Sheet Metal: For cutting mild steel, stainless steel, or aluminum under 6mm, a Fiber laser is unbeatable in speed.
- Reflective Metals: If you cut brass or copper, you must use Fiber. CO2 lasers struggle here because the heat is reflected rather than absorbed.
- Why not wood? If you try to cut wood with a fiber laser, it creates a serious fire hazard without actually cutting cleanly. The beam passes through the material and heats the metal bed underneath.
2. When to choose CO2 (Signage & Mixed Use)
CO2 is the king of versatility for makers, signage shops, and non-metal manufacturing.
- Acrylic: CO2 is the only choice for cutting clear acrylic with a “flame-polished” edge. Fiber lasers melt acrylic into a messy blob.
- Wood & Leather: Essential for cutting plywood, MDF, and leather.
- Thick Steel: High-power CO2 lasers (4kW+) produce a smoother edge quality on thick plate steel (above 20mm) compared to standard Fiber lasers, though high-power Fiber (10kW+) is closing this gap.
💰 Cost Implications
- Purchase Price:
- CO2: Generally cheaper upfront for equivalent wattage, especially in the hobby/prosumer range.
- Fiber: Higher initial investment, though prices have dropped significantly (you can now get entry-level industrial fiber cutters for under $15k).
- Running Costs (The “Per Hour” Cost):
- Fiber: Costs 50% less to run than CO2. No optical mirrors to replace, no laser gas (He/N2/CO2 mix) to refill, and vastly lower electricity bills.
- CO2: The consumables (mirrors, lenses, gas) and higher power draw make it more expensive to operate over time.
🏆 Verdict
- Choose Fiber if: Your business is 90-100% metal cutting. You want high speed, low maintenance, and energy efficiency.
- Choose CO2 if: You are a sign shop, job shop, or hobbyist working with wood, acrylic, plastic, and occasionally thin metal. You need flexibility more than raw metal-cutting speed.