Blade molded surface allowance removing method

According to the blade profile allowance removing method, punching is conducted in advance before grinding and polishing, the punching depth is smaller than the depth of the allowance needing to be removed, the hole serves as a reference during grinding and polishing, and due to the fact that the punching depth is smaller than the depth of the allowance needing to be removed, grinding and polishing are not excessive when grinding and polishing do not exceed the bottom of the hole; the blade profile size does not need to be detected in the stage of grinding and polishing the depth above the hole bottom, so that the grinding and polishing efficiency and precision are improved, and when the hole bottom is ground and polished, an operator knows that the allowance depth needing to be removed is reached at the moment, so that the grinding and polishing force is reduced, the problem of blade scrapping caused by excessive grinding and polishing can be avoided to a great extent, and the product quality is improved. An