Hammer is the main striking tool, which consists of a hammer head and a hammer handle. Hammer can be divided into derusting hammer, nipple hammer, mechanical hammer, claw hammer, inspection hammer, flat-tailed inspection hammer, derusting hammer, octagonal hammer, German octagonal hammer and nail hammer. The weight of the hammer should be suitable for the workpiece, material and function. Too heavy and too light will be unsafe. (1) The main function of the hammer is to roughly correct the original damage of the steel plate, so that the damaged part can be roughly restored to its original state. For small-scale depressions or protrusions, a finishing hammer can be used for finishing. (2) Skills of using a hammer When using a hammer, the hammering force is related to the weight of the hammer and the speed provided by the arm. The weight of the hammer is doubled, the hammer energy is doubled, the hammer speed is doubled and the hammer energy is quadrupled. When shaping the car body, the wrist is mainly used to swing the hammer, which is called wrist swing. This hammer pendulum method has small hammering force; Swing the hammer with the wrist and elbow is called elbow swing, which has great hammer force; The method of swinging the wrist, elbow and whole arm together is called swing arm, and the hammering force is the greatest at this time. Note: 1. Ensure that the hammer handle is firmly installed before use, and remember not to use a hammer with a loose or damaged hammer handle, so as to avoid accidents caused by the fall of the hammer head. 2. Use a hammer of appropriate size and quality for operation. 3. When the hammer surface is excessively worn, cracked or mushroom head appears, it should be trimmed or replaced to avoid personal injury caused by steel plate damage or splash. 4. When hammering, the hammer surface should be parallel to the panel to avoid uneven stress or hammering with a hammer angle. When hitting tools such as punches and mirrors, the hammer face should be proportionally larger than the heads of these tools. 5. Keep the hammer handle clean and free of oil or sand to prevent it from slipping.