Clear iron filings, oil dirt and welding slag on the granite surface with a plastic scraper and compressed air gun. Seal all threaded holes and positioning holes with rubber stoppers to prevent cleaning agents and polishing powder from seeping into internal structures and causing secondary contamination. Separate two types of surface damage: rust stains from metal oxidation and scratches caused by friction or impact, and use targeted cleaning processes respectively.
1. Removal methods for rust stains
Light surface rust film
Take neutral special granite rust remover free of strong acid ingredients, dip a lint-free soft cloth and wipe rust areas in circular motions. Let the agent stay for 3 to 5 minutes to decompose iron oxide deposits. After rust disappears, wipe the platform twice with a water-moistened clean cloth to wash away residual liquid, then dry thoroughly.
Deep embedded rust spots
Mix superfine granite polishing powder with neutral detergent into a thick paste, spread the paste evenly over rust spots and rub gently with a soft sponge pad. The fine powder can lift rust particles trapped in stone pores without scratching the base plane. After cleaning all paste residue, completely dry the surface.
Forbidden operations: Never use hydrochloric acid, oxalic acid and other strong acid rust removers. Strong acid will corrode granite grain boundaries, form tiny pits and permanently damage flatness and measurement precision.
2. Repair methods for scratches
Shallow micro-scratches (only faint traces without depression)
Use ultra-fine diamond polishing paste and soft wool polishing pads. Polish scratched areas with low pressure in cross directions until scratch traces fade and surface gloss recovers. Wipe off polishing paste residue with degreasing cloths and blow dry. This method will not cause material loss and can restore original flatness.
Medium & deep impact scratches with obvious grooves
Fill scratch grooves with granite repair glue matching the stone’s thermal expansion coefficient. After the glue fully cures, scrape excess glue flat with a straight ruler. Carry out progressive fine polishing with diamond abrasives from coarse to ultra-fine grade to unify the flatness and gloss of repaired areas and surrounding surfaces.
Deep scratches accompanied by tiny cracks
Clean all debris inside cracks before filling repair glue to avoid air bubbles. Complete polishing afterward, then test flatness with standard measuring tools to verify accuracy still meets the original grade standard.
3. Post-cleaning protective treatment
After removing rust and repairing scratches, coat the entire working surface with a thin layer of granite anti-fouling sealant. The sealant fills micro-pores on the stone surface, blocks penetration of oil and iron powder, and slows the generation of rust and scratches during daily workshop use. Conduct flatness re-inspection and record data for later precision tracking.
4. Daily preventive measures
Place copper or plastic gaskets between metal workpieces and the granite surface to reduce direct friction. Clear cutting fluid and iron filings after each shift to avoid long-term oxidation and rust infiltration. Do not drag sharp steel workpieces randomly across the platform surface.
Reference List
GB/T 7714 Format
Chen L. Repair and cleaning technology of scratch and rust defects on precision granite measuring platform[J]. Equipment Maintenance, 2022(9): 71-75.
MLA Format
Chen, Lin. "Repair and Cleaning Technology of Scratch and Rust Defects on Precision Granite Measuring Platform." Equipment Maintenance, vol. 9, 2022, pp. 71-75.
APA 7th Format
Chen, L. (2022). Repair and cleaning technology of scratch and rust defects on precision granite measuring platform. Equipment Maintenance, 9, 71–75.
