Difference between flame cutting machine and plasma cutting machine Also known as oxy-fuel cutting machine, the flame cutting machine is used to cut mild steel or low carbon steel, which can also be worked by plasma cutting machine. But there are some differences between flame cutting machine and plasma cutting machine. For the cutting quality, flame cutting machine has an excellent cutting effect form 15mm, while plasma cutting machine can produce excellent cutting effect till 25mm. For the operation cost, flame cutting machine need to rework, while plasma cutting machine can result in a lower cost than that of a flame cutting machine.