The bottom of the circular bottom knife has a curved edge and is generally semi-circular. It is mainly used for processing circular grooves, curved surfaces, chamfers, rounded corners, and decorative lines. It cuts smoothly and can mill standard circular arc surfaces in one go, avoiding multiple tool connections and ensuring smooth and beautiful curved surfaces. The blade has strong rigidity and good stability during processing, suitable for materials such as wood, acrylic, plastic, soft metal, etc. Commonly used in woodworking modeling, handicraft relief, aluminum profile arc groove, and product appearance rounded corner treatment. When in use, the speed is moderate, the feed is uniform, and the corresponding tool can be selected according to the radius of the arc. When machining curved surfaces, the tool path is coherent, reducing vibration patterns and improving the overall smoothness and forming effect of the workpiece.