The laser cutting technology revolutionized how we manufactured and produced objects across industries. LASER, an acronym for Light Amplification by Stimulated Emission of Radiation, was developed and improved since the 1970s. It is less prone to warping and has increased precision and reduced wastage and contamination.
A laser cutter is a computer-controlled machine. It can be programmed through various designing software. It uses a laser beam to accurately cut, etch or engrave different materials. It can melt, burn or vaporize the contacted area. It is a process of manufacturing parts by the direct reflection of the laser beam on the material to cut out specific geometry shapes.
Laser Power Of Laser Cutting Machine
It can increase and decrease the total processing time for the application. It is used to cut materials into customized shapes and designs. It is a non-contact thermal-based fabrication process.
It can laser cut acrylic, glass, paper, metal, mild steel, steel plate, and non-metals. Higher power laser can engrave, etch or cut thick materials like metals and gemstones. Lower power is required for cutting thin materials like paper, fabric, and leather.
The Wavelength Of Laser Cutter
The wavelength determines the absorption rate of radiation. It is the spatial length of one complete cycle of vibration for a photon within the beam. The smaller wavelength has a much higher intensity. They can cut through thicker materials.
The Frequency Of Laser Cutting
The frequency is to determine the rapidity of laser pulses during the cutting process. It is the number of pulses per second. It depends upon the material properties and thickness. If the laser is turning on and off very frequently while cutting, then the high frequency will create a cleaner cut. This does not apply to flammable materials like paper and wood. It might catch fire. So use low frequency while using such materials.
The Speed Of Laser Cutter
The speed of laser cutting is a crucial factor. You can change the speed of the laser head according to the kind of cutting you need. Increase the speed for cutting thin sheets. Decrease the speed for cutting thick materials.
High speed will cut faster but it may not cut well through thick material at one go. A low speed will cut through. But there are chances of burning or melting the edges of the material.
Importance Of Laser Beam
The Laser cutter machine generates beams according to material properties and laser cutting applications. The laser originates from the laser resonator. It sends a beam through the lens to the cutting head. Earlier the beam was directed via mirrors. Now fiber optic does the same.
The beam is focused to a small spot of high intensity. The point at which the beam’s diameter is the smallest is called the focal point of focus. As its narrowest, a laser beam is under 0.33mm in diameter. Due to the very small beam, it can create very fine and small designs with precision and quality. But if the beam remains in a specific place for a longer time, it will create a lot of heat. This may cause fire accidents if not regulated carefully.
The pulsed beams have a shorter wavelength. They travel very frequently. They are on and off beams in high speed used for scribing and cutting delicate designs. The continuous wave beams are long and continuous beams. They are suitable for high efficiency and high-speed cutting application.
Three Main Types Of Laser Cutting Tasks
The laser cutters are very powerful machines. They can perform the following task in precision-
LASER CUTTING
Laser cutters are known for their precision and clean-cut than mechanical mills. The cutting of the material varies due to different physical and chemical properties. Reflectance and surface thickness is the most important factor while laser cutting.
- Laser Fusion Cutting: This process is used in melting material in columns by using a high-pressure stream of gas. It removes the molten material and leaves an open-cut kerf. It completely cuts the material. It is a faster process.
- Ablative Laser Cutting: It removes material layer by layer. The beams work like chisels. It evaporates the material rather than cutting it. It is used to make partial cuts. Thus, a time-consuming process.
LASER ENGRAVING
During the engraving process, the laser beam removes the only upper part of top materials. It does not cut through the entire piece.
LASER MARKING
In the process of marking, the laser does not remove or cut the material completely. It changes color the color of the material. Lasers are used in engraving color in the marking process. They oxidize material like wood until it changes its color. By adjusting of laser wavelength, speed, focus point, and material type, you can achieve the surface finish.
LASER CUTTING DESIGN SOFTWARE
Laser cutter drivers read vector paths in a designed software program. Specific drivers are used to transferring data from a computer into a format that can be read by the cutter. It can process-
VECTOR IMAGE: This format stores lines and colors in mathematical formulas.
RASTER IMAGE: This is a pixel-based image format. They can break resolution during certain enlargement.
Software For 2D Cutting
CorelDRAW is a high-quality design software with a lot of tools applications. Adobe and QCAD are also popular for high-quality design. AutoCAD is used for detailed design. Inkscape is a free and open-source graphic design software.
Software For 3D Cutting
You can opt for Autodesk Fusion cloud-based CAD platform. Autodesk 123DMake software allows to make a 3D model and slice it up into layers of laser-cut pieces. You can assemble them later. Other software is Blender, Solidworks, and Onshape.
The Process Of Laser Cutting
The designer design something in the design software and then send it to the laser cutter via computer drivers. The drivers will convert the data which can be read by the cutter. After running the command, it will generate beams. The beams will go through the nozzles with the help of mirrors or beam-benders. The special lens will focus the laser beam in one spot. It will melt or evaporate the material from the spot.
CAD vector files will be in formats like .ai, .dxf, and .eps. Make sure that the color setting is in RGB format. The measurements should be in millimeters. However, different lasers require different file formats. So, go through the machine manual thoroughly.
Main Types Of Laser Cutting Machines
Different types of laser cutters are based on the different laser machine up-gradation. It has different power ranges, frequencies, beam strength, and kerfs. The major components of laser cutting include a laser resonator, mirrors or optic fibers, laser-cutting head, focussing lens, pressurized gas assembly, and a nozzle. The laser is focused on a focal point with the help of reflecting optics. It reads computer code to cut or burn the material. The process uses a motion control system to follow a CNC or G-Code pattern.
CO2 Laser Cutter Machines
They are most popular than the rest of the lasers. It generates electrically stimulated gas mixtures. It uses radio-frequency energy instead of electrodes. They are capable of cutting materials like wood, textiles, paper, acrylic, and some kind of foam, plastic, and leather. They are used for cutting, boring, and engraving purposes.
CO2 laser cutting machines have the infra-red spectrum wavelength. These rays are invisible to the eyes. They use electromagnetically stimulated gas as their laser medium. These gases range from a mixture of Carbon dioxide, Nitrogen, Hydrogen, Xenon, and Helium.
CO2 laser cutting provides better edge quality in thick materials like gemstones and metals. They cause smaller burns. They consume less power. Thus they are cost-effective and easy to maintain.
Fiber Laser Cutter Machines
The fiber laser cutters are more powerful than the CO2 laser cutting machines. The machine’s lasers are made of seed laser. They are amplified by glass fibers and diodes. They are used in heavy industrial production. It can process metal as well as non-metal materials. They can cut all reflective metals in the proper setup. Materials like Copper, Brass, and Titanium are easy to cut. But the material thickness can limit cutting ability.
It has high output while processing thin sheets. They are used for the laser marking processes on metals and plastics also. The laser power intensity and wavelength are similar to Neodymium lasers. They are popular in the metal cutting industry. However, it requires high maintenance, proper cleanliness of nozzles, and lens protection devices. Their replacement parts are quite expensive.
ND: YAG Laser Cutter Machines
The neodymium yttrium-aluminum-garnet laser or Nd: YAG lasers are capable of large cuttings. They use crystal and diodes to generate a laser beam. They provide industrial-grade cutting and manufacturing in various sectors. The crystal laser technology is used in the welding process. They are used in wood, metals, ceramics, plastics, and other materials.
Neodymium laser machines have a smaller wavelength than CO2 laser cutters. Due to the high intensity of the beam, they can laser cut through a thicker and stronger material surface. They can high-power laser boring and engraving on wood, acrylic, metals, and non-metals. They require high maintenance and proper cleanliness of the machine parts and surface. Machine parts can wear during laser works easily. Thus, they are an expensive lot.
Uses Of Laser Cutting
Laser cutting services serve many purposes in art, prototype, and manufacturing. They have the ability to fasten the production with precision in less time. Designers, artists, and engineers use a laser cutter to cut, etch, or engraving into mild steel and metal sheets. The focused industrial lasers can cut through a wide variety of materials. However, it is hard to cut brittle materials with the laser.
High-power fiber lasers increase the quality and repeatability of the cutting process. Laser cutting technology is popular in the aerospace, engineering, and automotive industry. It is not only used for manufacturing and production in industrial sectors but also popular among hobbyists, small-scale businessmen, and educational institutions.
