If you are prone to pitching rusty nails and screws, you probably have always thought you were doing the safe, responsible thing. After all, they represent a potential hazard and are useless, right? Wrong. Most rusty screws are actually still entirely serviceable, if you remove the rust, of course. This can be done using an entirely green cleaning agent that you probably have in your kitchen pantry.
Check the label on your vinegar. It must be undiluted. Many vinegar products are cut with water to reduce their acidity, but you need them to be pretty strong to remove this rust.
Fill the airtight container 2/3 full of vinegar. Leave at least an inch at the top, though, so that when you place the screws in the container it will not overflow.
Leave the screws in the vinegar bath for 24 hours. Once you have submerged them in the bath, put the lid on tightly. You can shake the screws every few hours to dislodge the rust.
Scrub the screws with a toothbrush under warm, running water. In the vinegar, all or nearly all of the rust will have come off. However, you can remove any remaining flecks by scrubbing the ridges of the screw with the toothbrush while you are scrubbing off the vinegar.
Dry the screws completely. Do not let them air-dry, but rather rub them completely dry with the cleaning rag. If your rag starts to get damp, switch to a new one or you will just have the beginnings of new rust on the screws in a little while.