In the overhaul work of metal cutting machine tools, it is often encountered to replace the new lead screw and the light bar, and the matching parts (sets, clutches, cranks, etc.) do not need to be replaced. The lead screw, the light bar and the fitting are generally connected by a tapered pin. How to make the taper pin hole on the new lead screw and the light bar to keep it concentric with the original taper pin hole on the fitting, so that the fitting is not scrapped. We have found a good way in many years of overhaul work, simple and reliable, and to ensure concentricity. The following takes the X51 vertical milling machine table screw and clutch as an example to introduce the specific method as follows: