Many different, old locks can be picked and reopened using a range of simple techniques and tricks. Anyone can try unlocking old furniture or stiff, old doors, but there is no guarantee of success so it might be necessary, eventually, to contact and pay a professional. Whether you are struggling to unlock a bike lock, an old wardrobe door has got locked and jammed or a piece of precious antique furniture needs reopening, you can try several tips before consulting a locksmith. Many old locks are simple designs, although a few were made with up to three anti-picking devices, according to Old Lock and Key.
Identify the age and type of the lock if you can as it might help when trying to find a replacement key. Some door systems date back to the 1500s, as explained by Info 4 Security. Try looking it up or asking a locksmith for his opinion on its date of production. Remember, most locks in use today are cylinder pin locks --- a type of dead lock, according to Science Ray --- but if the lock is very old, this will not be the case.
Try a similar shaped key to the one you are missing since some old locks are not as specific and intricate as their modern counterparts. Apply a short, sharp spray of a lubricant like WD40, which will not cause damage to old furniture or doors, but will enable you to turn the key more freely.
Take a photograph of the lock in daylight. Try to create an image that shows the shape of the lock and some of its internal structure if possible. Alternatively, create a size-specific cast using modelling clay. Approach a locksmith and ask if he can suggest a suitable key or selection of keys. Ask to try a few out or purchase one or two that might fit and try those.
Shape the end of a wire coat hanger into a spike. Gently tease the internal mechanism of the old lock. Aim to lift or slide any catches or loops. Look and feel for the mechanism giving way, then push the wire farther. Try to open the door or lid of the object you are unlocking. Ask for assistance if you think it will help.
Try a clever trick if you have access to the back of the cabinet or wardrobe. Open the back by unscrewing it with a screwdriver, if possible, or cutting a small section of the back of the furniture out with a saw. Do not damage expensive furniture in this way. Access the lock from the inside. Adjust the lock directly to open it or pull on the cables to unlatch the catches.
Consider a last resort method such as forcing the door or lid open. Only try this if you are more interested in getting into the locked object or through the locked door and do not mind your old lock getting broken. Pry apart the two locked surfaces slowly to reduce the damage. Use a chisel or crowbar if the door is large and heavy.
Take care when using tools like crowbars. Open doors away from your body to avoid injury. Wear thick gloves to protect your fingers from being trapped.