Old keys are often used in a multitude of craft projects as they often have interesting shapes--but sometimes old means dirty. Cleaning up non-important keys so that they can be used for jewellery, artwork or designs varies from removing the grunge of long wear, to stripping off decades of filth. The first step is to give the keys a good cleaning in soap and water.
Scrub the keys using soap and water to remove general dirt. Many keys only need a scrub with a nylon bristle brush to clean up completely.
Place a small crock pot outside with an extension cord on (a nice day). Place the keys in the bottom of the pot and pour vinegar to cover the keys. Heat the vinegar for about 30 minutes (it stinks). Allow the mixture to cool.
Remove the keys. Rinse the keys in water. Moisten a rag with paint thinner and wipe off each key to remove any grunge.
Place keys in a disposable plastic container or crock pot. Pour Coca-Cola drink over the keys. Place the lid on the container and let the keys sit in the soda drink overnight or 24 hours. Remove and wash with soap and water and dry thoroughly.
Lubricate and protect your clean keys with a metal polish.
Clean cheap keys fast by holding the key with vice grips, and holding the key to a spinning wire wheel. Wear safety goggles to protect your eyes. The wire will strip off all the dirt on the key.
Fragile or valuable keys should be cleaned by an expert who can use more gentle techniques for preserving the integrity of the keys.
Using a wire wheel should be done cautiously since the wheel can throw off small bits of wire which can cause injury. Always wear protective eyewear.