A fibre laser is a type of solid-state laser that generates a high-energy beam through a doped optical fibre, then focuses it onto metal to cut, engrave or mark with precision. Fibre lasers have become the dominant cutting technology in modern fabrication workshops because they cut faster, cost less to run and require less maintenance than CO2 lasers, while handling a wider range of metals including mild steel, stainless steel, aluminium, brass and copper.

If you’re considering a fibre laser for your workshop, understanding how the technology works, what it can and can’t do, and how it compares to the alternatives will help you make a confident decision.

How a Fibre Laser Works

The core of a fibre laser is an optical fibre, typically made from silica glass, that has been doped with a rare-earth element such as ytterbium. Semiconductor diodes pump light energy into this fibre, exciting the atoms inside it. As those atoms release energy, they produce photons of a specific wavelength, and mirrors within the fibre (called Bragg Gratings) bounce that light back and forth to amplify it into a concentrated, coherent laser beam.

That beam is then delivered through a fibre-optic cable to the cutting head, where it’s focused onto the workpiece. An assist gas, usually nitrogen or oxygen, blows away molten material from the cut path, leaving a clean edge.

The entire process happens within the fibre itself. There are no mirrors to align, no gas tubes to maintain and no warm-up time. You switch it on and start cutting.

What Can a Fibre Laser Cut?

Fibre lasers handle most metals you’d find in a fabrication workshop. The thickness you can cut depends on the power of the laser source, measured in kilowatts (kW).

Material	Typical Max Thickness (6kW source)
Mild steel	Up to 20mm
Stainless steel	Up to 12mm
Aluminium	Up to 10mm
Brass	Up to 6mm
Copper	Up to 6mm
Titanium	Up to 6mm

Higher power sources (10kW, 12kW and above) push these limits further. A 12kW fibre laser can cut through 25mm+ mild steel with good edge quality.

Reflective metals like brass and copper require adjustments to power settings and cutting speed. Modern fibre laser machines include anti-reflection optics to protect the laser source from bounce-back light during processing. AFM’s range of fibre laser machinery from Ermaksan and Glorystar covers power outputs suited to these applications.

Fibre Laser vs CO2 Laser

CO2 lasers dominated metal cutting for decades. They generate a laser beam by passing electricity through a gas mixture (primarily carbon dioxide), and they still cut well, particularly on thicker materials. But fibre lasers have overtaken them for most sheet metal work.

The differences that matter on the shop floor:

	Fibre Laser	CO2 Laser
Cutting speed (thin metals)	Up to 5x faster	Slower on materials under 5mm
Energy efficiency	~30% wall-plug efficiency	~10-15% wall-plug efficiency
Reflective metals	Cuts brass, copper, aluminium well	Struggles with reflective materials
Maintenance	Minimal. No mirrors, no gas tubes	Regular mirror alignment, gas refills
Laser source lifespan	80,000-100,000 hours typical	20,000-30,000 hours typical
Running costs	Lower electricity, fewer consumables	Higher across the board
Thick mild steel (20mm+)	Capable, improving rapidly	Still competitive at extreme thickness

For workshops cutting predominantly thin to mid-thickness sheet metal (up to 12-15mm), fibre lasers are the clear choice. They cost less per hour to operate, produce less downtime and handle a broader material range. CO2 still holds an edge on very thick mild steel, but that gap closes with every generation of higher-power fibre sources.

If your current setup uses plasma cutting, the comparison is different again. Plasma handles very thick materials cost-effectively but can’t match fibre laser precision on thinner gauges or complex profiles.

What Power Level Do You Need?

Choosing the right power level depends on the materials and thicknesses you process most often. More power gives you faster cutting speeds and thicker capacity, but it also costs more upfront. There’s no benefit in paying for 12kW if your typical work is 3mm stainless steel.

A practical guide:

• 1-3kW suits workshops cutting primarily thin sheet metal (up to 6mm mild steel, 3-4mm stainless). Good for signage, light fabrication, prototyping and smaller production runs.
• 4-6kW covers the majority of general fabrication work. Handles mild steel up to 20mm, stainless to 12mm, and aluminium to 10mm with good speed and edge quality.
• 8-12kW+ targets high-volume production and thicker materials. Faster cycle times on mid-range thicknesses and the ability to cut 25mm+ mild steel.

AFM supplies fibre lasers across this range through the Ermaksan Fibermak and Glorystar lines, with machines available to see at our Cramlington showroom.

Maintenance and Running Costs

One of the strongest practical arguments for fibre lasers is how little they demand in day-to-day maintenance. The laser source has no consumable parts, no mirrors to align and no laser gas to replenish. A typical fibre laser source lasts 80,000 to 100,000 operating hours before it needs replacing, which for most workshops means well over a decade of use.

The main ongoing costs are assist gas (nitrogen or oxygen depending on the material), replacement nozzles and protective lenses for the cutting head, and electricity. All of these are lower than the equivalent costs for a CO2 laser running the same workload.

Planned servicing and maintenance still matters. Keeping the cutting head clean, checking the chiller system and maintaining the extraction unit all contribute to consistent cut quality and machine lifespan.

Choosing a Fibre Laser Machine

Beyond power level, several factors affect which machine suits your workshop:

Bed size. Match the bed to your most common sheet sizes. Standard options range from 1500 x 3000mm to 2000 x 6000mm. Larger beds reduce sheet handling time on bigger production runs.

Single table vs exchange table. An exchange (shuttle) table lets you load the next sheet while the machine is still cutting. For higher-volume workshops, this can significantly reduce idle time between jobs.

Flatbed vs tube. Flatbed machines cut sheet metal. Tube laser cutters handle round, square, rectangular and open-section profiles. Some machines combine both. AFM supplies both configurations, and we’ve covered tube cutting technology in more detail in our article on fibre laser tube cutting.

Software and CNC controls. Modern fibre lasers run through CNC systems with CAD/CAM software for programming cut paths, nesting parts efficiently and managing production files. Most systems use Windows-based interfaces that operators can learn within a few days.

After-sales support. A fibre laser is a significant investment. The machine’s value depends as much on the supplier’s ability to install, commission, train your team and provide ongoing support as it does on the specifications. Spare parts availability, engineer response times and service contracts all matter, particularly if the machine is central to your production.

A Technology Worth Understanding Before You Invest

Fibre laser technology has matured to the point where it’s the default choice for most metal cutting applications in fabrication workshops. The combination of cutting speed, material versatility, low maintenance and falling costs makes it a strong investment for workshops of all sizes.

The key is matching the right machine to your specific work. Power level, bed size, table configuration and supplier support all play a role.

If you’d like to see fibre laser cutting in action before making a decision, explore AFM’s range of fibre laser machinery or visit our showroom in Cramlington, Northumberland, where we run live demonstrations for customers evaluating their options. Our team can walk you through the options and help you find the right fit for your workshop.