FOCUS ON PLASMA CUTTING
Plasma is also typically cheaper to operate than oxy-fuel. Unlike oxy-fuel, plasma does not require the need to refill cylinders as often. For example, with thicker mild steel cutting, plasma uses less oxygen and is faster. Plasma also provides more precise cuts. A plasma cutter will produce more precise and clean cuts with better angularity, a thinner kerf, a smaller heat-affected zone and zero-to-no dross. The technology is also easier to master and more forgiving.
Ten plasma cutting tips
CNC plasma cutting is a versatile and efficient way to cut metal. With the right machine and techniques, users can achieve precise cuts, intricate designs and rapid production times.
However, to get the most out of your CNC plasma cutter, operators need to follow some best practices. Here are ten tips from Irish plasma cutting specialist, PlasmaCut. ie, for successful CNC plasma cutting.
1. Choose the right machine and consumables: Select a machine and consumables that are appropriate for the type of metal and thickness that you will be cutting. This will ensure optimal performance and reduce wear and tear on your equipment. Different metals require different machines and consumables, so choose the right ones for your application. For example, if you are cutting thin sheet metal, you might choose a machine with a lower amperage range and a smaller torch. On the other hand, if you are cutting thick steel plate, you might need a machine with a higher amperage range and a larger torch.
2. Set the correct amperage and gas pressure: Adjust your amperage and gas pressure to match the thickness and type of metal that you are cutting. Refer to your machine’ s manual or consult with a technician for guidance. The amperage and gas pressure settings are critical to achieving clean and accurate cuts. If your amperage is too low, you may not be able to penetrate the metal, resulting in a rough or incomplete cut. If your amperage is too high, you risk overheating the metal or damaging your consumables. Similarly, if your gas pressure is too low, you may not be able to achieve a clean cut while if it’ s too high, you risk blowing out the arc and creating an erratic cut.
3. Clean your metal: Clean your metal thoroughly before cutting. This will help to ensure accurate cuts and prevent damage to your consumables. Any dirt, oil or other debris on the metal can interfere with the cutting process and reduce the lifespan of your consumables. Use a clean, dry cloth or wire brush to remove any surface contaminants before cutting.
4. Use a proper ground: Ensure that you have a clean and tight ground connection. A poor ground can cause erratic cutting, poor edge quality and damage to your machine. The ground connection is an essential part of the cutting circuit and must be clean and tight to ensure optimal performance. Use a metal-to-metal connection to ensure a secure ground.
Image: PlasmaCut. ie.
Above: Plasma cutting. Inset: Plasma-cut materials.
5. Keep your consumables clean: Regularly inspect and clean your consumables to prevent build-up of slag or other debris. This will help to extend their lifespan and maintain their cutting performance. Slag is a byproduct of the cutting process and can accumulate on your consumables, reducing their effectiveness over time. Use a wire brush or other cleaning tool to remove any slag or debris from your consumables after each use.
6. Use appropriate speed and feed rates: Adjust your speed and feed rates to match the thickness and type of metal that you are cutting. This will help to ensure clean, accurate cuts and reduce the risk of overheating. The speed and feed rates refer to the rate at which your torch moves across the metal and the rate at which the metal is fed through the machine. Use a slower speed and feed rate for thicker metals and a faster speed and feed rate for thinner metals.
7. Consider the direction of the cut: Think about the direction of your cut when setting up your machine. Cutting with the grain or against it can affect the quality of your cuts and the lifespan of your consumables. When cutting with the grain, the metal is less likely to deform or warp, resulting in a cleaner cut. However, cutting against the grain can help to reduce the build-up of slag on your consumables, which can extend their lifespan. Consider the direction of the cut and adjust your machine settings accordingly.
8. Monitor your machine: Keep an eye on your machine while cutting to ensure that it is operating correctly. Look for signs of overheating, erratic cutting or other issues. If you notice any problems, stop the machine and investigate the cause. Regular monitoring can help to prevent damage to your equipment and ensure the quality of your cuts.
9. Properly dispose of waste: Dispose of your scrap metal and waste material properly. This will help to prevent accidents and keep your workspace safe and tidy. Scrap metal can be sharp and heavy, so it’ s important to handle it with care. Use a scrap metal bin or other designated container to collect your waste and dispose of it in accordance with local regulations.
Image: Kjellberg.
10. Practice regular maintenance: Regularly inspect and maintain your machine and consumables. This will help to ensure optimal performance, extend the lifespan of your equipment and prevent costly repairs. Follow the manufacturer’ s recommendations for maintenance and use only recommended replacement parts and consumables. Regular maintenance can also help to prevent downtime and ensure consistent quality in your cuts. n
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