Aluminum Etc.: You can cut aluminum on a CNC plasma system

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People still tell me confidently that you can’t cut aluminum on a CNC plasma cutting table—even as they watch me cut aluminum with a CNC table right in front of them.

Sometimes old information or a lack of awareness of the advancements that have been made in plasma cutting technology prevent CNC enthusiasts from making projects out of aluminum. With aluminum being both corrosion resistant and so much lighter than steel, they are really missing out!

Modern plasma cutting systems are more capable and adaptable to different materials than older models. So, yes, you can use a plasma cutting table to cut aluminum sheets.

Confusion about aluminum and plasma tables might occur because people do not understand three key points:

1. Material conductivity - Plasma cutting relies on the electrical conductivity of the material being cut. Aluminum is a highly conductive material, making it suitable for plasma cutting.
2. Material thickness - Plasma cutting is effective for a variety of material thicknesses, but the thickness and the power of the plasma cutter need to be matched appropriately. Frustration can occur if someone attempts to cut aluminum that is too thick for their plasma cutting setup.
3. Settings and gas selection - The settings and gas used in plasma cutting can impact cut quality. When cutting aluminum, specific adjustments in power settings and gas selection are necessary for optimal results. If these adjustments are not made, it may lead to poor cut quality and misconceptions about the process.

Some considerations and adjustments that need to be made when cutting aluminum with a plasma cutter include:

• Power settings - Aluminum has different thermal conductivity compared to steel, so you may need to adjust the power settings on your plasma cutter. Consult the manufacturer's recommendations for cutting aluminum with your specific machine.
• Gas selection - When cutting aluminum, it's common to use nitrogen or a nitrogen/argon mix as the plasma gas instead of regular compressed air. This helps prevent oxide formation on the cut edges and produces a cleaner cut. Make sure you don’t overlook this critical factor.
• Cutting speed - Aluminum generally requires a slower cutting speed than steel. Adjust the cutting speed according to the thickness of the aluminum sheet you are working with.
• Consumables - Make sure to use the appropriate consumables for cutting aluminum. This may include a specific type of nozzle and electrode designed for aluminum cutting.
• Cleanliness - Ensure the aluminum sheets are clean and free of any contaminants or coatings that could affect the cutting process.

Always refer to the manufacturer's guidelines and recommendations for cutting aluminum with your specific plasma cutting table. Additionally, it's a good idea to conduct test cuts on scrap material to fine-tune your settings before you begin your project. It's essential for individuals using a CNC plasma cutting system to be well informed about the specific requirements and adjustments needed for cutting aluminum.

I would love to see your aluminum CNC projects! You can email me pictures at ginac@bigbend.edu.