As the name suggests, laser cutters create patterns and designs by cutting into materials. A powerful laser beam is the source that melts, burns, or vaporizes the material.
Essentially, laser cutting is a fabrication process that uses a thin, focused, laser beam to cut and etch materials into custom designs, patterns, and shapes as specified by a designer. This non-contact, thermal-based fabrication process is ideal for several materials, including wood, glass, paper, metal, plastic, and gemstone. It’s also capable of producing intricate parts without needing a custom-designed tool.
A Bit of Background
The invention of the laser cutter is attributed to Kumar Patel, who began his research in laser action when he joined Bell Labs in 1961. In 1963, he developed the first C02 laser, which is the variant with more modern applications than any other type of laser. C02 lasers are for engraving materials ranging from acrylic and plywood to cardboard and MDF.
Today, laser cutting has found a home in industries such as electronics, medicine, aerospace, automotive, and semiconductors. One of the most common applications is for cutting metal – whether its tungsten, steel, aluminum, brass, or nickel – because lasers deliver clean cuts and smooth finishes. Lasers are also used for cutting ceramics, silicon, and other non-metals.
Perhaps one of the most intriguing uses of laser cutting technology is in the surgical field, where laser beams are now replacing the scalpel and are being used to vaporize human tissue. This is especially useful in high-precision surgical procedures like eye surgery.
We’ll talk about more applications in a later section, but for now, let’s see how the laser cutting process works.
A laser cutter’s beam usually has a diameter between 0.1 and 0.3 mm and a power of between 1 to 3 kW. This power needs to be adjusted depending on the material being cut and the thickness. To cut reflective materials like aluminum, for instance, you may need laser powers of up to 6 kW.
Laser cutting is not ideal for metals like aluminum and copper alloys because they have excellent heat-conductive and light-reflective properties, meaning they need powerful lasers.
Below are some core components of a laser cutter:
Three Major Varieties of Laser Cutting
Generally, a laser cutting machine should also be able to engrave and mark. In fact, the only difference between cutting, engraving, and marking is how deep the laser goes and how it changes the overall appearance of the material. In laser cutting, the heat from the laser will cut all the way through the material. But that is not the case with laser marking and laser engraving.
Laser marking discolors the surface of the material being lasered, while laser engraving and etching remove a portion of the material. The main difference between engraving and etching is the depth to which the laser penetrates.
Here’s the difference between marking and engraving:
Differences in laser cutters come from the types of lasers in the machines, and the kind of laser determines the type of material thickness the laser may be able to cut. Generally, a high-powered laser will be ideal for professional applications where large sections of plastic or metal need to be cut. On the other hand, a low-power laser is effective for thinner materials like plastics, card stock, paper, and wood.
The three main types of lasers are:
1. Gas Lasers/C02 Laser Cutters
The cutting is done using electrically-stimulated CO2. The CO2 laser is produced in a mixture that consists of other gases like nitrogen and helium.
C02 lasers emit a 10.6-mm wavelength, and a CO2 laser has enough energy to pierce through a thicker material compared to a fiber laser with the same power. These lasers also give a smoother finish when used to cut thicker materials. CO2 lasers are the most common types of laser cutters because they are efficient, inexpensive, and can cut and raster several materials.
Materials: Glass, some plastics, some foams, leather, paper-based products, wood, acrylic
2. Crystal Laser Cutters
Crystal laser cutters generate beams from nd:YVO (neodymium-doped yttrium ortho-vanadate) and nd:YAG (neodymium-doped yttrium aluminum garnet). They can cut through thicker and stronger materials because they have smaller wavelengths compared to C02 lasers, which means they have a higher intensity. But since they are high power, their parts wear out quickly.
Materials: Plastics, metals, and some types of ceramics
3. Fiber Laser Cutters
Here, cutting is done using fiberglass. The lasers originate from a “seed laser” before being amplified via special fibers. Fiber lasers are in the same category with disk lasers and nd:YAG, and belong to a family called “solid-state lasers”. Compared to a gas laser, fiber lasers do not have moving parts, are two to three times more energy-efficient, and are capable of cutting reflective materials without fear of back reflections. These lasers can work with both metal and non-metal materials.
Though somewhat similar to neodymium lasers, fiber lasers require less maintenance. Thus, they offer a cheaper and longer-lasting alternative to crystal lasers
Materials: Plastics and metals
Out the three, C02 lasers are used most commonly, by both makers and professionals. They are used primarily for cutting non-metal materials, and even though they have evolved to cut through metals, they are still better suited for non-metals and organic materials (wood, leather, rubber), and engraving hard materials.
Here are the reasons why laser cutting is preferred compared to other cutting technologies, such as CNC milling:
Key considerations when shopping for a laser cutter:
There are other concerns like the mechanics of the laser machine and the component parts, both of which can significantly determine how smooth and clean your cut will be.
Here are two of our favorite machines:
For even more, go through our comprehensive list of the best laser cutters.
Laser cutters work just like your regular inkjet printers. The machines have certain drivers that enable them to pick designs from the computer and to convert those designs into a readable format.
Several software packages can support the drivers of a laser cutter:
While the designer’s imagination is theoretically the only limitation to what can be created, here are some general guidelines when designing for laser cutting:
Once the design is ready and has been loaded on the machine, the laser cutting head will move over the metal plate following the directions of the design to cut the part as desired. The laser beam follows the vector file that holds the design to cut away at the material until the shape/pattern is completed.
Laser cutters have become handy tools for prototyping and manufacturing. They are being used:
Feature image source: soulcraftcle.org
License: The text of "What Is a Laser Cutter? – Simply Explained" by All3DP is licensed under a Creative Commons Attribution 4.0 International License.