Laser and plasma cutting are the two most popular methods of CNC cutting metal sheets in the metal industry. Here is a quick guide and insight into how each technique works.
What Is a Plasma Cutting?
Developed as an alternative to flame cutting in the 1950s, plasma cutting is the oldest form of cutting. Electrically ionised gases are fired from nozzles at high speeds toward the workpiece of the plasma laser cutter to superheat and ionise them during plasma cutting. The gas then forms an electrical arc. This electric arc creates electrically conductive plasma channels by ionising some of the gas. This plasma is heated by electricity as it travels down the cutter torch, melting through the workpiece. Hot molten metal is blown away by plasma and compressed gas.
Plasma Cutting – Advantages and Disadvantages
- It can achieve a faster cutting speed than CNC sheet cutting and flame cutting for a medium-thick plate, much faster than laser cutting or flame cutting.
- It is cheaper to invest in this equipment initially, and it requires much less future maintenance.
- Plasma metal cutter surface perpendicularity is poor: there is a large oblique cutting edge on one side of the cutting surface, and the surface is not perpendicular.
- Increase the production of cutting slag: cutting slag will accumulate at the bottom of the cutting surface during the cutting process. It is necessary to grind away this slag, which increases labour costs as well, so as not to affect the post-processing quality.
- Plasma cutting produces dust and arc light: Plasma cutting generates harmful gases and arcs during the cutting process.
What Is CNC Laser Cutting?
Developed in the 1960s, CNC laser cutting is a technique for cutting holes in diamond dies. In this process, high-power lasers burn, melt, vaporise, or blow away materials through oxygen, nitrogen, and compressed air. Laser beams are emitted from tubes, reflected by mirrors, and guided into the laser head. When you cut or engrave something with this machine, a lens inside the head focuses the beam on the surface of your CNC cutting sheet. A laser can either be a fiber laser or a CO2 laser.
Cost, Quality, Technology used, Precision
CNC Laser Cutting – Advantages and Disadvantages
- It is possible to weld directly from the cut surface without grinding if there are small cuts.
- This process allows thin sheets to be cut at 10 meters per minute, much faster than plasma cutting.
- The exceptional cutting quality is characterised by a small amount of deformation, low surface roughness, and a low degree of oblique cutting.
- With a positioning accuracy of 0.05mm and re-positioning accuracy of 0.02mm, the positioning system has a high level of precision.
- The machine can cut many materials, including metal, wood, plastic, rubber, PVC, leather, textiles, and organic glass.
- Cost is the number one factor.
- Investing in the first place and maintaining it later require higher costs.
- Currently, laser cutting is more cost-effective for thin plates.
- Due to the low efficiency when cutting thick plates, laser cutting isn’t suitable unless high quality is required.
Key Differences between laser cutting and plasma cutting
There are fundamental differences between plasma cutting and CNC plasma cutter. The plasma-cutting process uses plasma, while the laser-cutting process uses amplified laser light.
|Parameters||Laser Cutting||Plasma Cutting|
|By Principle||On the other hand, the laser cutting process involves the generation of laser beams by laser devices. To transmit laser beams, a series of reflectors are used. Once the beam has been focused on the workpiece, it is directed by a focus lens. Using the laser beam, you can create a smooth, high-quality surface finish by heating and melting the focal point.||Depending on the material, plasma cutting uses compressed gases such as oxygen, air, or inert gases. In this process, a plasma channel is artificially created through the workpiece. Due to the high temperature of the plasma, any object, no matter how thick, can be melted, evaporated, or burned.|
|By Application||Lasers have higher precision, direction, and intensity than lasers, which require no post-processing. It is also more cost-effective to use plasma cutting rather than CNC steel cutting.||Plasma-cut material’s range of options is limited compared to a laser-cut material’s wide range. Cutting thin sheets with lasers is better than cutting them with plasma. A plasma cutter is used when the following characteristics are needed: a small deformation, a quick cutting speed, a narrow cutting slot, and a small heat-affected area.|
|By Cost||Laser cutting is typically more expensive than plasma cutting, but it offers greater detail. Lasers can therefore be used to engrave details on metal or cut out small shapes.||Plasma, on the other hand, is less costly and is better for simple cuts. The plasma cutters can easily cut through thicker sheets of metal.|
|By Material||Lasers cutting technique is widely used in cutting wood, plastic, glass, and many other materials.||While only conductors of electricity can be cut by plasma. Because Instead of using an optical beam to create cuts, plasma uses electrically conductive gas.|
Which one to Use-Laser or Plasma?
There are many factors to consider when choosing a material, such as its thickness and type. A laser cutter offers greater accuracy and consistency, while a plasma cutter offers more versatility and requires a lower initial investment.
Laser cutters are suitable for thin or medium-thick parts with tight tolerances, high-precision cuts, or parts with tight tolerances.
Common uses for plasma cutters include cutting parts made of metals with high reflective properties, cutting parts made from thicker materials, and cutting simple shapes.
There is no one-size-fits-all approach when it comes to projects. We may choose to use a laser CNC machine or a plasma cutting machine depending on our time and budget constraints. In addition, how we get to the end product depends on the thickness and material of your project. Therefore, you can be sure that the final product will meet your expectations! Let a leading CNC laser cutting service like RP Lasertech’s experienced fabrication team know about your next project today!