WD-40’s low viscosity lets it work as an aerosol, allowing the fluid to reach even the smallest holes, gaps, cavities and cracks.
WD-40 is popular largely because it can help loosen stubborn threaded connections covered in rust, grime or other deposits. Its effectiveness comes from the way its ingredients work together. The volatile solvent, mineral spirits, breaks down and softens various types of contamination. Once the solvent evaporates, a nonvolatile lubricant, mineral oil, remains on the treated surface, helping protect the part and making threaded components easier to loosen.
Because WD-40 contains a solvent, it can also help remove grease and oil from your hands after working on a vehicle, such as during an engine rebuild.
Spray a small amount onto your hands and wipe them with a shop rag to remove the grime. Afterward, wash your hands thoroughly with soap and water several times.
Important: Prolonged skin contact with WD-40 should be avoided. Wash the product off your hands as soon as possible after using it.
Removing an old sticker from a surface can be surprisingly frustrating. No matter how carefully you peel it, the sticker may tear while the adhesive backing remains behind.
Instead of scraping the residue off and potentially scratching the surface, you can use WD-40. Spray a small amount onto the sticker or leftover adhesive, wait three to five minutes, and then wipe away the softened residue with a cloth.
The aerosol solvent can also be useful for removing permanent-marker writing from certain surfaces. Spray a small amount of WD-40 directly onto the mark or apply it to a cloth first.
Marker usually comes off fairly easily from smooth surfaces. If the writing is on a porous or textured material, you may need to wipe the area several times.
Tip: After using WD-40 on a nonmetal surface, wash the area with soapy water to remove any remaining solvent and lubricant.
WD-40 can also be used in a limited way to remove grime from vinyl records while leaving behind a light lubricating film. A small cloth lightly moistened with the product can be used to gently wipe the record and remove built-up waxy dirt.
However, this is one case where less is definitely more. Avoid soaking the record or rubbing it aggressively.
Even stainless steel can develop stubborn stains and mineral deposits over time. WD-40 can help loosen some of these deposits.
Spray the product onto the affected area and let it sit for about five minutes, giving the solvent time to penetrate the buildup. Once the deposits have softened, remove them with a plastic scraper. Repeat the process if necessary.
Tip: After cleaning the sink, wash the sink and any tools you used with warm water and dish soap to remove any remaining WD-40.
WD-40 can also be useful for loosening rust and other deposits from metal surfaces, including cast iron.
Apply the product to the rusted area and let it sit for three to five minutes. To slow evaporation, you can cover a pipe or other metal part with a shop rag lightly moistened with WD-40.
Once the rust has softened, remove it mechanically with a power sander, sandpaper or another suitable abrasive tool. The treatment can make the cleaning process considerably easier and can also leave the surface with a protective lubricating film.