Rust stains are some of the hardest to remove from fabrics, so feel free to say a few nasty words if you find such a stain on your clothing or furniture. Several common household products may work to remove the stain, including lemon juice, salt and white vinegar. If these remedies don't work, a commercial rust-removing chemical might. Proceed with caution, however, as the cures for rust stains can cause their own damage.
Lifting Laundry Stains
The fresher the stain, the easier it is to remove, so you'll want to spring into action like a laundry ninja as soon as you notice a stain. Lay the clothing out on an old towel and then completely saturate the area with salt and either lemon juice or white vinegar. Dab at the stain with a clean white towel to transfer as much of the stain as possible from the garment to the towel. Never rub the stain as this will spread it, and never use a colored towel – doing so may transfer dye from the towel to your clothing, creating an entirely new stain. Continue working the stain until the rust stops transferring to the towel. When it does, set the garment outside in direct sunlight for several hours before washing it as you normally would.
After washing, take the garment out of the washing machine and thoroughly inspect it before placing it in the dryer. Once the garment is exposed to the heat of the dryer, the stain is set and removing it is a lost cause. If the stain is still present after the wash, pour some commercial rust-removing solvent onto a clean white cloth and use it to dab at the stain. Lighten the stain as much as you can and then launder the garment again.
Fixing Furniture Fabrics
You can't just pop your couch into the washing machine if you find a rust stain on it, so you'll need a different approach for stained carpet and furniture. To treat stains on these fabrics, first sprinkle the area liberally with salt. After salting, completely saturate a clean white cloth in white vinegar, ring it out and lay it over the stain and salt. Let the cloth sit on the stain for at least 30 minutes before checking the stain. Apply a fresh vinegar-soaked cloth if it's still present. Continue adding fresh towels and allow them to work for 30 minutes at a time until the stain is gone. When the stain has vanished, remove the cloth and allow the fabric to thoroughly dry before vacuuming up the salt.
If the stain is stubborn and refuses to lift, consider applying a commercial rust-removal solvent by soaking a cloth in it and dabbing the stain. Furniture and carpets are more expensive to replace than clothes, so absolutely always test any chemical solvents on an inconspicuous area before using them.
A Word of Warning
Did you ever put lemon juice in your hair and then sit in the sun hoping your hair would lighten? Well, the properties of lemon juice haven't changed, and it still works as a bleaching agent. As a result, applying lemon juice to your clothes could permanently discolor them. White vinegar, too, can damage clothing and other fabrics. Vinegar is acidic, so while it works wonderfully as a cleaning agent, it can eat holes in materials. It's important to recognize these facts before using lemon juice and vinegar to treat a rust stain. You could remove the stain, but you could also ruin your clothing.
It's also important to avoid using bleach on a rust stain, even if the stain is on white fabric. Bleach is an oxidizer and rust the product of oxidization, so bleach will make a rust stain worse. You must also use white vinegar on fabric and never a colored one, such as red vinegar. Colored vinegar stains fabric.
If you view an item with a rust stain as a loss, it makes sense to try and fix the stain yourself. You can't further damage something that's already ruined. If, however, you're concerned about having to replace an expensive fabric item, remember to always test your cleaning solution in an inconspicuous area. Remember, too, that there's no shame in visiting your local dry cleaner for help. You can also call a professional carpet or furniture cleaner to examine the stain for you.