Casting surface defect repairing method

The invention discloses a casting surface defect repairing method. The method comprises the steps that S1, an electric drill is used for drilling a hole shrinkage position in a milling face of a casting; s2, preparing an insert; s3, an insert is embedded into the drill hole; s4, the surface of the insert is polished through a file; s5, carefully grinding a high point on the upper surface of the insert by using a small-granularity abrasive oilstone until the upper surface of the insert is flush with the repaired surface of the casting; s6, measuring the flatness of the repaired surface of the casting, and if the flatness does not meet the technical requirements, repeating the step S5 until the flatness is qualified; and S7, the repaired surface of the casting is polished through 2000-mesh fine abrasive paper so that the roughness of the repaired surface can be guaranteed. The required tools are simple and convenient to carry and use, and the repaired casting surface is smooth, flat and attractive; the method i