The precision testing of high-precision mirror shaft rods is a key step in ensuring their quality. The following are some commonly used testing methods:

1、 Dimensional accuracy testing

Caliper measurement

For basic dimensions such as the diameter and length of the shaft rod, high-precision calipers can be used for measurement. Calipers with a general accuracy requirement of 0.01mm or even higher can preliminarily detect whether the shaft rod is within the design dimensional tolerance range. When measuring, ensure that the caliper is in vertical and smooth contact with the surface of the shaft rod, and take the average of multiple measurements to reduce human error.

Micrometer measurement

A micrometer can provide more accurate dimensional measurements, with an accuracy of up to 0.001mm. By rotating the ratchet, the measuring anvil and micrometer screw are brought into contact with the shaft rod, and the values are read from the dial. For key dimensions such as outer diameter and inner diameter of high-precision mirror shaft rods, micrometers are essential testing tools. Moreover, measuring at different positions and directions can comprehensively evaluate the dimensional uniformity of the shaft rod.

2、 Shape accuracy detection

Roundness meter detection

The roundness meter detects the roundness of a shaft by rotating it and measuring the distance change from the surface of the shaft to the center of rotation using a high-precision sensor. For high-precision mirror shaft rods, roundness error is usually required to be in the micrometer level. It can accurately detect whether there are defects such as ellipticity, local protrusions, and depressions on the surface of the shaft rod.

Straightness detection

Using an optical straightness measuring instrument, utilizing the principle of linear propagation of light. Place the shaft rod on the measuring platform and measure the straightness of the shaft rod busbar using equipment such as laser beams or optical collimators. If the straightness of the shaft rod does not meet the requirements, deviations may occur during equipment installation or movement, affecting its performance.

3、 Surface roughness detection

Roughness meter detection

The roughness meter measures the fluctuation of the micro profile of the surface by tracing the surface of the shaft rod with a stylus and moving it up and down. It can measure surface roughness parameters such as Ra (arithmetic mean roughness). For high-precision mirror shaft rods, the Ra value is generally required to be very low, possibly at the nanometer level, which requires the use of high-precision roughness meters for detection.

Optical microscope and electron microscope testing

An optical microscope can observe the microstructure of the surface of the shaft rod and make preliminary judgments on larger surface defects or processing marks. Electron microscopes can provide higher magnification and resolution, and can be used to detect surface defects and roughness at the nanoscale, ensuring that the surface of the shaft meets the requirements of high-precision mirror surfaces.

During the testing process, it is necessary to strictly follow the relevant standard operating procedures and conduct the testing under suitable environmental conditions (such as constant temperature, constant humidity, dust-free, etc.) to ensure the accuracy and reliability of the testing results.