Know Your Lasers: CO2 vs Fiber?

Purists may say you have to have a fiber laser to cut metal, but that's not entirely true.

Yes, fiber lasers cut metal faster, with smaller beams, so they are more accurate and use less power. Fiber lasers are also easier to use and less expensive to maintain in the long run. However, fiber lasers are typically twice as expensive as CO2 lasers, and they cannot cut a wide range of materials.

Let's take a closer look at the differences.

CO2 lasers are produced by sending an electric current through a glass tube filled with CO2 and other gases. At the end of this sealed glass tube are two mirrors, and the current flowing through the tube intensifies the gases, causing them to produce light. The light is reflected around some cleverly placed mirrors inside the laser cutter, then focused by the lenses and leaves the device to hit the surface of the material you are working on.

CO2 lasers may be cheaper, but they always require the use of oxygen or nitrogen as a gas assist and are limited to cutting metals with low reflectivity. CO2 lasers are also sensitive machines. Due to the combination of mirrors and glass tubes, they are very fragile and need to be perfectly aligned to function optimally. This leads to maintenance and repair costs that are more expensive in terms of time and money. Nevertheless, this is still balanced by their affordability.

Fiber lasers are a new technology in the field of laser cutting. At the industrial level, they are commonly used to cut thin metal sheets for production parts. In desktop form, they are still expensive machines, but they do offer many advantages, including power efficiency and fewer moving parts.

In a fiber laser, the laser itself is produced by an optical fiber with the addition of rare earth elements such as erbium, ytterbium or neodymium. Fiber lasers do not require an auxiliary gas to perform cutting. The laser produced by this method is very stable and easy to focus.