Abnormal noise during CNC Machining may be caused by various reasons, such as loose equipment components, tool wear, spindle motor problems, etc. To solve this problem, the following measures can be taken: 1. First, it is necessary to stop the machine for inspection and determine the source of the abnormal noise. This can be judged through observation, hearing, and touch. If the abnormal noise comes from loose equipment components, it is necessary to tighten the relevant components to ensure their firmness and reliability. 3. If the abnormal noise comes from tool wear, it is necessary to replace the tool with a new one or repair it. 4. If the abnormal noise comes from a problem with the spindle motor, it is necessary to check the status of the spindle motor, including the motor bearings, gears, and other parts, to ensure its normal operation. 5. In addition, it is necessary to check the lubrication system of the equipment to ensure that it receives sufficient lubrication to reduce the occurrence of abnormal noises. If the above measures cannot solve the problem, you can consider conducting a comprehensive inspection and maintenance of the equipment, or contacting professional technicians for diagnosis and repair.