According to the relevant data and practice, the repeatability of the tool setting probe is 1 um, and that of the chuck less than 15 inches is 5 um. The repeated accuracy of the tool arm can reach 8um for the chuck of 18 inches and above. This precision can meet the needs of most users without trial cutting. The use of tool setting instrument reduces the auxiliary time of the machine tool and reduces the rework and scrap rate. The efficiency and accuracy of the machine tool can be significantly improved when the machine tool is used from the beginning to the end.