A fiber laser cutting machine is one of the most deceptively specified pieces of fabrication equipment you can buy. The brochure almost always leads with a single number - the laser power in kilowatts - and lets everything else ride on that headline. But the document that actually decides whether the machine earns its floor space is the spec sheet underneath: the cutting table, the assist-gas options, the automation wrapped around the beam, and the integration of the motion system. If you are comparing a fiber laser cutting system from a manufacturer that also builds laser welding robots, the same discipline applies, because both machines share a laser source, the same motion-control engineering, and the same service expectations. This guide walks through the spec sheet line by line so that two quotes from two vendors can finally be compared on the same footing.
The first mistake buyers make is to open the conversation at laser power. Power is the last thing you should fix, because it is the easiest thing to oversize and the most expensive thing to oversize wrongly. What you actually need to know first is the work envelope: the maximum sheet size the bed will accept, the maximum part height the cutting head can clear, and - for 3D robotic cells - the reach and articulation of the robot. A flatbed fiber laser is constrained by its table; a robotic cutting cell is constrained by the robot's working volume and the fixture that holds the part. Write down your three largest recurring parts and your thickest recurring material before you read a single kilowatt figure, and you will immediately disqualify half the machines that look attractive on the front page.
Laser power sets the maximum cutting speed at a given thickness, and it sets the thickest material the machine can process at all. The trade-off is cost: higher power means a more expensive resonator, more electrical demand, and more aggressive cooling. For precision 3D laser cutting in particular, manufacturers openly note that many customers open by asking for 3 kW, 6 kW or higher, yet a 3 kW fiber laser is frequently described as the point that gives the best balance between cutting capability and system cost. That is a useful anchor. Below 3 kW you gain economy but lose the ability to process thicker sections or hold speed on high-mix work; above 6 kW you pay steeply for capacity you may only use on a handful of jobs. The right answer is driven by your thickness distribution, not by the sales chart.
When you read a power claim, ask which material it is measured against. A machine that cuts 20 mm carbon steel at 3 kW is a different proposition from one that cuts 20 mm stainless at the same power, because stainless and aluminium absorb and conduct heat very differently. A spec sheet that quotes a single thickness without naming the material is not a spec sheet - it is an advertisement.
A flatbed fiber laser cuts flat sheets on a gantry. It is fast, repeatable, and easy to automate with shuttle tables and automatic loading. A 3D robotic laser cutting system mounts the laser head on a six-axis robot and cuts complex curved surfaces - tube ends, pressed brackets, hydroformed sections, and welded assemblies that cannot be laid flat. The core value of 3D robotic cutting is exactly that ability to follow a contoured part instead of a plane. If your work is flat plate, a robotic cell is the wrong tool; if your work is shaped components, a flatbed cannot reach them at all.
Several manufacturers publish robot-integrated cutting lines built on mainstream industrial arms. For example, laser cutting robots are offered in FANUC, Yaskawa and ABB series alongside the builder's own series, with 2 kW and 3 kW configurations shown in the published product range. The robot brand you choose has consequences for the rest of your plant: if you already run FANUC welding robots, a FANUC cutting robot shares controllers, programming training and spare servo axes with equipment you already service.
Almost every fiber laser cut is made with an assist gas blowing through the cut zone. The gas is not optional, and the choice changes the edge you get and the cost you pay. The simplest comparison is worth committing to memory before you sign:
| Assist gas | Best for | Edge quality | Running cost |
|---|---|---|---|
| Oxygen | Carbon steel, thicker sections | Oxidised edge, needs light deburr | Low gas cost, higher speed |
| Nitrogen | Stainless, aluminium, clean edges | Bright, oxide-free, paint-ready | Higher gas cost, slower on thick |
| Compressed air | Thin gauge, cost-driven work | Acceptable on thin stock | Lowest, but limited thickness |
None of these is universally correct. Oxygen gives you speed and low gas spend on mild steel but leaves an oxide layer that matters for coatings and welds. Nitrogen gives you a clean, oxide-free edge on stainless and aluminium that is ready for painting or further welding, at the price of gas consumption and reduced speed on thick sections. Air is cheap but only defensible on thin material. The spec sheet should state which gas the quoted speed and edge claim assumes - if it does not, you do not have a comparable quote.
The table is where the part actually lives, and it silently governs throughput. Bed size decides your maximum sheet; load rating decides whether you can stack heavy plate; and the table mechanism decides whether the machine stops for every load. A single fixed table forces an operator to stand in the beam enclosure unloading finished parts while the laser sits idle. A shuttle or exchange table lets the next sheet be staged while the current one cuts, which can lift real utilisation without any change to cut speed. If you are quoting a machine for production rather than prototype work, ask specifically whether the quoted cycle time assumes an exchange table or a manual single bed - the two are not the same machine in practice.
Tube and profile cutting is a separate axis of capability. Some flatbed machines accept a rotary attachment; some robotic cells cut tube ends as part of a shaped part. If your parts include any open section, ask whether the machine cuts it natively or whether it needs a secondary operation. That answer changes both the capital cost and the labour per part.
The laser head is only one component of a cutting system. The productivity lives in what feeds it and what takes away from it: automatic sheet loading and unloading, shuttle tables, fume extraction, and the nesting software that packs parts onto a sheet. A fast cutter starved of material is just an expensive space heater. When you read the spec sheet, separate the beam spec from the handling spec, and recognise that lights-out running depends almost entirely on the handling side. Ask for the manufacturer's stated load or unload method and whether the nesting software is included or licensed separately - a quoted cut speed means little if you are manually placing every sheet.
Because many cutting and welding systems are built around industrial robots from FANUC, Yaskawa or ABB, the robot brand is a service decision as much as a performance one. Standardising on one robot platform across cutting, welding and handling cells means one programming discipline, one spare-parts pool for servo motors and controllers, and one service relationship. A manufacturer that both integrates leading robot brands and develops its own series - established in 2013 and holding ISO 9001 and CE certifications, as one such builder publishes - gives you a path to standardise without being locked to a single source. When you compare quotes, write down the robot brand and model on each, then price the annual spare-parts holding for that platform; the difference can exceed the resonator saving.
The single most useful thing you can do is refuse to accept a one-page quote. A comparable request for quotation forces every vendor to answer the same questions, and it surfaces the gaps that brochures hide. The checklist below is the minimum:
| Parameter | What to ask | Why it matters |
|---|---|---|
| Material and thickness range | State each alloy and its max thickness | Power and gas claims are material-specific |
| Sheet size and bed | Max sheet, load rating, exchange table? | Decides throughput and handling labour |
| Assist gas | Which gas for the quoted speed or edge | Changes edge quality and running cost |
| Automation | Load or unload, nesting licence, lights-out | Beam speed is meaningless if starved |
| Robot brand | Platform and model on robotic cells | Drives spare-parts and training cost |
| Certifications | CE, ISO 9001, enclosure class | Compliance and resale value |
| Commissioning and training | Install, FAT or SAT, operator training days | Hidden cost if quoted separately |
| Warranty and lead time | Resonator warranty, delivery weeks | Cash-flow and downtime exposure |
Hand the same table to every vendor. The quotes that come back with blanks are the ones to discount first, not the ones to negotiate hardest.
Start from your thickness distribution rather than a headline number. A 3 kW fiber laser is widely cited as the balance point between capability and cost for precision cutting, with 6 kW and above justified only when thicker sections or high-mix speed dominate your work. Specify your three thickest recurring materials and let the power follow.
If your parts are flat plate, a flatbed is faster and easier to automate. If your parts are shaped, contoured, or welded assemblies that cannot lie flat, only a 3D robotic cutting cell can reach them. The decision is driven by part geometry, not by budget alone.
Oxygen is faster and cheaper on carbon steel but leaves an oxidised edge. Nitrogen gives a clean, oxide-free edge on stainless and aluminium that is ready for coating or welding, at higher gas cost. Choose per material, and insist the quote states which gas its claims assume.
Use a fixed RFQ checklist - material and thickness, bed and exchange table, assist gas, automation, robot brand, certifications, commissioning and warranty - and require every vendor to answer each line. Quotes with blanks are the first to discount.
Yes. Systems built on shared FANUC, Yaskawa or ABB platforms let a single programming discipline, spare-parts pool and service relationship cover both laser cutting and laser welding cells, which lowers lifetime cost even if the upfront price is similar.
A fiber laser cutting machine is bought on its spec sheet, not its brochure. Read the envelope before the watts, fix the assist gas to your material mix, and treat the table and automation as half the machine. Standardising on a robot platform that also spans welding protects you on spare parts and training for years. If you want to see how a manufacturer that builds both laser cutting and laser welding systems presents its capabilities, the TrueSyn industrial laser cutting robots are a useful reference for the questions above, and its company profile documents the integration depth and certifications worth asking every vendor about.