Manipulation is the process of opening a combination lock, using only the eyes, ears and hands. Although an electronic listening device or stethoscope could be employed, this manual will teach you how to manipulate, void of all devices.

Movies and TV have created many false ideas about safe manipulation. The locksmith, detective, or spy usually sandpapers the finger tips, carefully listens as the "tumblers fall, " and promptly opens the safe after dialing only one set of numbers.

Manipulation is strictly a mechanical procedure. The technique outlined in this manual utilizes the natural characteristics of the lock mechanism. These characteristics are the result of two things: the design of the mechanism and the manufacturing tolerances.

To practice these techniques, it will be necessary for you to obtain a lock the same as, or very similar to the one used for study and mount it on a small stand. With this set-up you simply follow the assignments. Just a few hours practice will allow you to gain the self-confidence of being able to manipulate.

Every locksmith should know how to manipulate or at least be familiar with the principles involved. This knowledge will allow you to handle all safe servicing and combination changing in a more professional manner. It is to that end that this manual was written.

It is dedicated to the countless locksmiths, locksmithing students and law enforcement agents who have never before had the opportunity to learn the techniques of manipulation.