Daily cleaning is essential. During use, jigs accumulate various metal shavings, oil, and dust. Just like in a machining workshop, when lathe jigs are used to process parts, shavings constantly fly onto the jigs. After each use, they must be cleaned promptly. Use a brush to carefully remove surface metal shavings, especially in the crevices and grooves of the jig, where dirt easily accumulates. For oil stains, use a clean cloth dampened with a suitable amount of specialized cleaning agent to wipe them clean. For example, jigs used to hold parts in auto repair shops often come into contact with engine oil and require repeated wiping to clean them thoroughly. After cleaning, wipe them dry with a clean cloth to prevent residual cleaning agent or moisture from corroding the jig surface.
Inspect the fixture for wear. Critical components such as the locating and clamping surfaces of the fixture are prone to wear due to frequent use. For example, in mold manufacturing plants, injection mold fixtures open and close dozens of times a day, causing gradual wear between the locating pins and locating holes, leading to decreased positioning accuracy. Regularly check the dimensions and shape of these parts using calipers, dial indicators, and other measuring tools. If wear exceeds the specified range, repair or replacement must be carried out promptly. For high-precision aerospace parts machining fixtures, even a wear of 0.01 mm requires treatment; otherwise, the machining accuracy of the parts will be affected.
Proper lubrication of fixtures is essential. Moving parts on fixtures, such as guide rails, lead screws, and hinges, require regular lubrication to reduce friction and extend their lifespan. In automated production lines, guide rails endure significant sliding friction daily; without timely lubrication, they will quickly wear out. Specialized lubricating oils or greases can be used; lithium-based grease is well-suited for general mechanical fixtures. When applying grease, clean the surfaces of moving parts thoroughly, then apply it evenly, ensuring every area is lubricated. For fixtures with oil filling holes, lubricate according to the prescribed schedule, generally every 50-100 hours of operation.
Store fixtures properly. Fixtures not used for extended periods should be stored in a dry, well-ventilated place to prevent moisture and rust. In some southern factories with high humidity, fixtures may rust within days if left unattended. Fixtures can be placed on dedicated shelves, with a layer of rust-preventive oil applied to their surface, and then wrapped in plastic film. For precision fixtures, they also need to be placed in a temperature- and humidity-controlled environment to prevent temperature and humidity changes from affecting their accuracy. For example, precision fixtures used in optical lens processing have extremely high requirements for their storage environment; unsuitable conditions can cause fixture deformation and affect the processing quality of the lenses.
Perform regular accuracy calibration. After a period of use, the accuracy of fixtures may decrease, requiring regular calibration. In automotive parts processing plants, engine block machining fixtures need to be calibrated periodically using a coordinate measuring machine to ensure that positioning accuracy and clamping force meet requirements. During calibration, if any deviations are found, adjustments should be made promptly. For some simple clamps, fine adjustments can be made by adjusting shims, bolts, etc.; for complex clamps, professional technicians need to use specialized equipment for calibration and repair.
