Three Precautions During the Operation of Universal Tool Microscope
Follow the correct focusing sequence for the eyepiece and objective lensMany users start by focusing with the objective lens during measurement. After focusing on the object, they align the crosshair reticle for measurement and adjust the eyepiece if the reticle is unclear. This sequence is incorrect, as it creates a slight ghosting effect on the focused image of the measured object. The proper procedure is to first sharpen the crosshair reticle in the eyepiece, then focus on the object. This ensures both the reticle and the object image remain clear.
Remove burrs and indentations from the workpiece surface before measurementWorkpieces often develop tiny burrs and indentations during machining, handling, or transportation. These subtle defects can easily cause alignment errors on the universal tool microscope or create local ghosting by shifting parts of the measured surface out of the focal plane, reducing measurement accuracy. All surface burrs and indentations must be thoroughly removed beforehand.
Install the workpiece correctlyThere are two common mounting methods for workpieces on a universal tool microscope:
(1) Mounting flat workpiecesEnsure the measured surfaces lie on the same focal plane; otherwise, local ghosting will occur. For parts with chamfers, place the chamfer facing downward to avoid unclear focusing and inaccurate measurements.
(2) Mounting shaft-type workpiecesShaft workpieces are usually positioned by center holes. Thoroughly clean the center holes before installation, especially removing sand, debris, and burrs. Failure to do so will misalign the workpiece axis with the instrument's centerline, leading to significant measurement errors. After installation, check the runout of the shaft's outer diameter using the horizontal line of the reticle to verify correct mounting.
