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. You'll need to record a lot of information in order to crack a safe. Not only are line graphs an easy way to do so, the shape of the graph will aid you in finding the data you'll need. Each graph's x-axis should cover a span from 0 to the highest number on the dial face, spaced out enough to clearly graph points 3 numbers apart or closer. The y-axis only needs to cover a span of about 5 numbers, but you can leave it blank for now. Label one graph's x-axis "starting position" and its y-axis "left contact point". Label the second graph's x-axis "starting position" and its y-axis "right contact point". Spin the dial several rotations clockwise to disengage the wheels, then set it at the zero position. You're trying to find the contact areas where the drive cam connects to a wheel (see Learn How a Combination Lock Functions). Make sure to note the exact number you heard each click. You'll need two separate points, usually within a few numbers of each other. On your "left contact point" graph, make a point at x=0 (the number the dial began on). The y-value is the number on the dial where you heard the first click. Similarly, on your "right contact point" graph, mark a point at x=0 and a y value where you heard the second click. You can now label your y-axes. Leave enough room to graph a spread of 5 numbers on either side of the y-value you just recorded. Spin the dial clockwise a few times and set it 3 numbers further clockwise of zero. This new number is the next x-value you'll record. Find the new y-values of the first and second clicks when you start at this location. They should be near where you heard them last time. When you've recorded the second location, reset the lock again and set it an additional 3 numbers counterclockwise. Once you've mapped the entire dial (in increments of 3) and are back at the zero position, you can stop testing. At certain x-axis points the difference between the left and right contact point values (y axis) will be smaller. This is easier to see if you lay the two graphs one above the other and literally find the points where the two graphs are closest together. Each of these points corresponds with a correct number in the combination. You should know how many numbers there are in the combination, either because you've used this safe previously or because you followed the instructions for Find the Combination Length. If the quantity of converging points on the graph doesn't match the quantity of numbers in the combination, make a new graph and see which points are consistently narrow. If the y-values on the two charts are closest together when x=3, 42, and 66, write down these numbers. If you successfully followed these steps, these numbers should be the ones used in the combination, or at least close enough to work. Note that we do not know which sequence of these numbers is the correct one. Read on for additional testing and tips.

Summary:
Set up two line graphs Label each graph. Reset the lock, then set it to zero. Rotate slowly counterclockwise and listen. When you hear two clicks close together, note the position of the dial at each click. Graph these points. Reset the lock and set it 3 numbers left of zero. Continue recording the location of the two clicks. Keep testing until your line graphs are done. Look for points on your graphs where the two y-values converge. Write down the x-values at these locations.