Yes, you can use a grinder to cut aluminum coil, but it's essential to choose the right type of grinder and blade. A metal cutting grinder with a suitable blade designed for cutting aluminum is recommended. Ensure the blade is sharp and the grinder is powerful enough to handle the material. Always wear appropriate safety gear, including gloves and eye protection, as cutting aluminum can produce sharp edges and flying debris. Be cautious of the heat generated during cutting, as it can warp or damage the aluminum.