Rust stains give us another laundry situation where cream of tartar is a great green hero -- it has an acidic quality that enables it to break down rust. First, cover the rust stain with cream of tartar. Next, tie up the area surrounding the stain, making the fabric into a pouch. Soak the entire pouch in very hot water for about five to ten minutes, then untie it and launder as usual.
Salt and vinegar also work well as rust removers on fabric. Combine salt and vinegar into a thin paste and then spread the paste onto the stained area of the fabric. Next, lay the item out in the sun to bleach it. If sun is not an option, stretch the fabric over a large bowl or pan, secure the fabric, and pour boiling water through the stained area. Whether you use sun bleaching or the hot water method, allow the item to dry on its own. Run the item through a rinse cycle in your washing machine, or give it a good hand rinsing, and then check the stain again. If any of the stain remains, repeat the treatments. Never put the fabric through the dryer until you're certain the stain is gone.