CO2 Versus Fiber Laser: Cost to Cut a Part

Editor’s Note: Don Hoffman has decades of experience with laser cutters and brings to the table a combination of independence, research skills, and thoughtful analysis. Here he tackles a moving target, with appropriate care and cautions, to write a useful guide to the relative per-part costs with CO2 and fiber lasers.

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CO2 laser, flat-material cutting machines have been around for more than 20 years while fiber laser cutters first gained acceptance in 2008. What a difference six years make! Important changes that took 15 years with CO2 lasers, took fiber lasers less than three years. That is, to go from a kW to 4kW with reliable performance.

When fiber lasers were first introduced, at IMTS in 2008, there were only a couple of companies demonstrating them at the show; and they were first introduced at the 2kW level. Contrast that with virtually every major fabrication machine manufacturer, who were showing and demonstrating a startling variety of CO2 laser cutters.

Since that introduction in 2008, virtually every laser cutting machine manufacturer, and some companies brand new to the flat-sheet laser cutting industry, have introduced a fiber laser cutter, or cutters, to their laser cutting machine line.

Both fiber and CO2 laser cutters are work horses in industry with both machines, now at 4kW, having the demonstrated ability to cut plate up to 0.787”; and thicker.

While there are CO2 laser cutting machines available from 250 watts to 6kW, the most prevalent laser power supplied for CO2 flat sheet laser cutting machines has been 4kW. Interestingly enough, fiber laser cutters are available in power levels from 2kW to 6kW, again with the 4kW fiber laser being the most prevalent power supplied. Why are there more 4kW flat laser cutters sold than all other laser powers combined? I cannot say for sure, but my guess is that the technology available for the machine itself, combined with a 4kW laser, is currently the best price/performance ratio available.

Which machine, fiber laser cutter or CO2 laser cutter, would make the most sense for your company? I submit that this choice is dictated by which machine makes your parts for less money; in some cases a lot less money. This article cannot define the costs to make your parts, but it can define the cost to make certain parts, and speaking with potential machine suppliers can help you get a handle on the cost to make your parts.

Laser cutting machine manufacturers have the ability to do time studies on their machines with your parts. Take advantage of it, because that’s the only sure way to nail down you actual, individual costs. In the meantime, we can describe relative costs for the two types of machines.

The Most Important Cost Items That Contribute To the Cost To Make a Part

Here are the key ones. There are other cost items that are important to the overall cost per part. I have focused here on the cost items that are the primary cost drivers in laser cutting. Other cost items are listed later in this article. (Note that all the information below is based on 4kW laser cutting machines, whether fiber laser or CO2 laser.)

Operating cost and cutting speed are the two most important cost drivers.

Operating cost

Operating costs vary, of course, so we will use an “average” cost of $12.73/hour for 4kW CO2 laser cutter. The actual cost will vary from somewhat less to somewhat more.

Based on available data, we will use $6.24/hour for a 4kW fiber laser cutter.

Cutting speed

Again, it is not possible to cover cutting speeds for every 4kW CO2 laser cutter so we will use an “average” cutting speed for these machines. Some CO2 laser cutters may cut a bit faster and some a bit slower. Note that these examples are for brand new laser and beam delivery optics and assume that the optics are in correct alignment. Cutting speeds will drop over time.

Based on available data, we will use the below cutting speeds for a 4kW fiber laser cutter. Note that neither the fiber laser itself, nor the fiber optic beam delivery system of a fiber laser cutter, include individual optics. Without these optics, the cutting speeds should remain constant over time.

Material and thickness cutting speed, and cost to cut 100 ft. of material, cutting cost comparison

This information is derived from publicly available data. If possible, do your own calculations based on your cutting experience. Again, the bottom line is a time study or studies on your parts. These relative values will give you a place to start:

Material/thickness/cutting gas CO2 laser cutting speed and cost to cut 100 ft. of material Fiber laser cutting speed and cost to cut 100 ft. of material:

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*Cutting cost per 100 ft. of material is based on operating cost as stated and cutting speed as stated. While these cutting speeds and operating cost are not the same for every laser cutting machine available, they are a useful place to start when considering a laser cutter. Any math errors are mine.

Secondary Cost Items That Also Contribute to The Cost to Make a Part

– Laser rebuild costs- With certain CO2 lasers, this cost can add $4.00/hour+- to your operating cost.
– Ability to common line cut- This can actually be slower but it often can significantly reduce scrap and make more parts out of a given sheet of material.
– Machine acceleration and deceleration- Especially important in thin gauge metal
– Laser rebuild costs– With certain CO2 lasers, this cost can add $4.00/hour+- to your operating cost.
– Ability to common line cut– This can actually be slower but it often can significantly reduce scrap and make more parts out of a given sheet of material.
– Machine acceleration and deceleration– Especially important in thin gauge metal
– Laser reliability– Fewer components means less complexity and more reliability
– Laser beam stabilityOverhead– Faster cutting speeds means less fixed costs assigned to a part
– Labor– Faster cutting speeds means less labor cost per part
– Material– This usually does not affect part cost
– Cutting gas– Faster cutting means overall less gas used
– Optics in laser– Optics wear mean lower cutting speeds
– Optics in beam delivery system– Optics wear and out of alignment means lower cutting speeds
– Focus lens length– Longer FL lenses usually mean longer lens life. Like nd: YAG laser machines, fiber lasers often have a “sacrificial”, relatively inexpensive, optic below the focus lens.
– Spot size– Generally speaking, a small spot size means higher power density and faster cutting speed.
– Beam quality– When discussing CO2 laser cutters, the beam quality is often defined by a TEM or a 1/e square rating with TEM00 being a “perfect” beam; not necessarily to best beam mode for cutting plate.

With fiber lasers, the beam quality is usually defined by BPP (Beam Parameter Product) with the lower the BPP the better the beam for cutting. A primary contributor to low BPP is the diameter of the beam delivery fiber. Smaller beam delivery fiber means a lower BPP which means a “higher” beam quality (smaller spot size with all other things being equal) for laser cutting.

Laser automation: The use of automation, for laser cutters, can significantly decrease manpower costs and can often allow you to run the laser cutter in a “lights out” condition. If you go as far as automatic load (from a tower or towers) and include automatic unload/sort/stack capability, with scrap destruct, you can significantly increase part production; of course this also increases total machine cost so a careful analysis should be done to determine the best level of automation for your company.

Do these, secondary, cost items really change the cost of an individual part. Yes, and that change can be significant to your bottom line.

Rebuild costs: If you do not know that you will have a significant rebuild cost, and do not add it into your part cost or quoting process, you may be in for an unpleasant surprise. When investigating operating cost (a direct contributor to part cost) ask for the total estimated operating cost over at least 30,000 hours (five years in a three shift operation).

Cutting gas: Fiber laser cutters may consume a bit more cutting gas, per hour, than a CO2 laser cutter. This may be offset by the fiber laser having a higher cutting speed and other, lower, operating costs.

Good luck with your “cost to cut parts” investigation and I trust that this has been helpful with your final decision.

Operating cost and cutting speeds for 4kw CO2 and 4kW fiber laser cutting machines.

The operating cost and cutting speeds defined in the comparison chart are calculated from publicly available, and published, information provided to the public by a variety of laser cutting machine manufacturers.

The exact information is not meant to be definitive but as a comparison between the two laser technologies. Current technology is changing and the costs and cutting speeds will change dynamically as manufacturers address issues related to nozzle design, focus lens length, and other pertinent data points. In other words, the operating costs and cutting speeds are not static. Some 4kW (fiber and CO2) laser cutters may be a bit faster and some may be a bit slower than those listed in the charts. The exact difference is less important, to you the potential user, than the relative difference between the two technologies. Please note that CO2 laser cutters have been around for a long time and their cutting speeds may have a limited upside potential, while fiber lasers are a somewhat younger technology and the cutting speeds may have a significant upside potential.

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