Cream of tartar, often used as a stabilizing agent in foods, functions as a key ingredient in one homemade rust remover. Mix it with water until it resembles toothpaste, then rub it into the stain. Allow it to sit on the rust stain for a while, then remove it with a clean cloth.
Lemon Juice and Salt
When put together, lemon juice and salt work well at removing rust stains from clothing. Be cautious as this method may remove color from some fabrics, along with the rust. Scatter salt over the stain, then drizzle lemon juice over the area. Place the piece of clothing in sunlight to dry. Launder the clothing as normal.
Borax and Lemon Juice
Lemon juice also functions as a key component in another rust-removal concoction. Mix lemon juice with borax until it reaches a pasty consistency. Apply the mixture to a rust spot, allow it to dry, and rinse it clean.
Undiluted white vinegar may also help remove stubborn rust stains. Apply it to the affected area, let it sit for a few minutes, and wipe it with a clean, damp cloth.