Finding the combination:

You have chosen group 4. Your first number is one of the following:

3. 7, 11, 15, 19, 23, 27, 31, 35, 39

Your second number is one of the following

1, 5, 9, 13, 17, 21, 25, 29, 33, 37

If you have bought a new lock to practice on and given the combination to a friend, have your friend verify that your have the third number correct and that the first and second numbers are above.

You may now construct a list of the 100 combinations and start dialing them, in the normal way. List the ten combinations which start with 3 (3-1-__, 3-5-__, 3-9-__, etc.), followed by the 10 combinations which start with 7(7-1-__, 7-5-__, etc.), then 10, etc. so you have all 100 combinations, and line out each one after you try it. (Fill in the blank __ with the third number in your combination.) However, there are really only 64 valid combinations. It is not easy to describe which combinations to skip, but, if you have Microsoft Excel installed on your computer, click on the "Combination Lock Spreadsheet" link below to open an Excel spreadsheet. Enter your last number in the designated cell, cell E1, and a table of possible combinations will be generated. Use the browser's back button to return here.

Combination Locks Spreadsheet

Or, you may try the following method, which takes a little learning, but really speeds up the process and saves on the fingers, and makes it easy to skip the unused combinations.

Jot down the numbers in the group 4 (or print out this page.).

Rotate the dial right twice or more around and stop carefully at the first number, 3. Rotate the dial left once around back to 3 and then two marks further to 5. Now rotate right to your last number. Pull up on the shackle. If the lock doesn't open, rotate the dial left back to the number you just tried as a second number (5) and then 4 more to the left (9) Now, right to the last number. Try the shackle again. If the lock doesn't open, left to the number 4 more than the one just tried, (13) and right to the last number. Pull up on the shackle. If the lock doesn't open, left to 4 more than the second number just tried (to 17) and right to the last number.

Caution: at some point, when you dial the next second number, you will pass over the third number.
Only turn the dial right far enough to reach the third number! The time before it took nearly a full turn, and this time the third number is only two marks away!

Keep count of the second numbers tried and stop after the eighth number is tried (33). If the lock doesn't open, try the second possibility for the first number, 7. (Always turn the dial right at least two turns before dialing a new first number.)Test eight second numbers, one at a time (9, 13, 17, 21, 25, 29, 33, 37) If the lock hasn't opened, try the third possibility for the first number (11), dialing eight second numbers one at a time as before. Continue until all the first numbers are tried. The lock should open. If it doesn't, you may have the wrong third number, or you may have missed the correct combination.

More Ways to Save Wear and Tear on Your Fingers!

On some locks, the dial will bind at all the fake sticking places. If so, the following method will not work. However, if you can one or more sticking places where the dial doesn't bind, you can use them to test whether you have the correct first two numbers, and reduce the amount of dialing.

How to Use Sticking Places to Test Whether You Have the Correct First and Second Numbers.
If you have the correct first two numbers and pull on the shackle, the dial will bind or move only a small amount at EVERY fake sticking place (except, possibly, the sticking places that are almost a full turn to the right of your second number.) After you dial your second number, turn right to the first sticking place you reach. Remember that the sticking places are only 3 or 4 marks apart, so you won't have to turn the dial too far to get to a sticking place. However, don't use a sticking place which you know is fake because you already felt binding. Pull on the shackle and move the dial back and forth. If the dial turns freely between the two stopping places, and the stopping places haven't moved closer together, you don't have the correct first and second number. Don't bother to dial your third number and try to open the lock, just continue with the next second number. If the dial binds or doesn't turn as far as it did before at that sticking place, you MAY have the correct first and second number. Turn the dial LEFT to the next sticking place you reach and make the same test. If you find any sticking place where the dial moves freely, you don't have both the first and second number right, so continue with the next second number. If the lock doesn't open at the number you thought was the correct third number but you feel binding, continue trying sticking places, since you have the wrong third number and the lock may open at a different third number.

Refining the technique further when you are sure of the third number: The numbers two marks before and two after the third number are also not used, so they can also be safely skipped. For example, if the third number is 10, it is not necessary to try 8 (two before) and 12 (two after) as a second number in the combination.

Once you have opened the lock, you have the three numbers in the combination. The combination may be dialed in the normal way. Exception: if your third number is not one of the numbers above, your first and second number may be off by one on the lock dial. Use your browser's back button, find your actual third number and click on the link. Find first and second numbers that are off by one from the numbers you dialed. Note that 0 and 39 are off by one from eachother on the lock dial. (The lock allows for sloppy dialing and may open if the numbers are off by one. The lock should open more reliably with the correct numbers.)

Helpful Hint: When you turn the dial left and reach the second number you just tried, the dial normally becomes a little harder to turn. This helps with remembering the second number just tried.

Click on one of the links below.

You succeeded!

You Failed.

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