Lock Outs, Lock Picking and General Locksmithing

[mothman]

FOR EDUCATIONAL PURPOSES ONLY

I am going to write this as quickly as I can and at the same time try and make it as clear as possible. If something is unclear, than reply with your question and I will answer it ASAP.

This technique of finding the combination to a master padlock will only work on older locks (It will still work on some of the newer locks, but is no longer guaranteed to work). Master locks have discovered this exploit and made changes to their locks (Master Lock changed where they place the drive pins on the combination wheels), so it is no longer guaranteed to work. You can tell if this exploit will work from the serial number on the back of the padlock, but I don’t remember the serial numbers that no longer work, so if anyone knows, please post it.

Go to this post to see how a Master Lock Combination Padlock works: http://www.keybitslockandkey.com/losangeleslocksmith/forum/viewtopic.php?t=201

Turn the dial on the Padlock three times to the right and stop at zero. Now take the padlock in your hand and apply tension to the shackle by pulling on it, and at the same time turning the dial slowly to the left. After turning past a few digits the shackle will pop out slightly and the smooth range of movement of the dial will between two numbers. These two numbers will either be whole numbers or decimals, such as 3.5. Record the two numbers and release the shackle slightly and begin turning the dial again until the shackle pops out and the dial stops between the next set of numbers. Record the numbers and continue this process until you have rotated the dial one complete turn. At the end of the complete turn you should have recorded a total of 12 sets of numbers.

Here are the 12 sets of numbers I recorded for my padlock:

1. 3 and 4
2. 5.5 and 6.5
3. 8.5 and 9.5
4. 12 and 13
5. 15 and 16
6. 18.5 and 19.5
7. 22 and 23
8. 25 and 26
9. 28.5 and 29.5
10. 32 and 33
11. 35 and 36
12. 38.5 and 39.5

Now take each set of numbers and add them together and divide by 2 and record the answer.

1. (3+4) / 2 = 3.5
2. (5.5+6.5) / 2 = 6
3. (8.5+9.5) / 2 = 9
4. (12+13) / 2 = 12.5
5. (15+16) / 2 = 15.5
6. (18.5+19.5) / 2 = 19
7. (22+23) / 2 = 22.5
8. (25+26) / 2 = 25.5
9. (28.5+29.5) / 2 = 29
10. (32+33) / 2 = 32.5
11. (35+36) / 2 = 35.5
12. (38.5+39.5) / 2 = 39

Notice that most of the answers from the calculation end in .5 and these numbers we can discard. We only want the whole numbers. So from my example the numbers I want to keep are: 6, 9, 19, 29 and 39. Now discard all the numbers that end in the same digit, so the numbers I discard from my example are 9, 19, 29 and 39, so I am left with 6. 6 is the last number in the combination to my padlock, and with this number we can narrow down the possible combinations from approximately 64,000 to 100.

Now take the last number in your combination and mod it by 4. This simply means you take the last number in your combination and divide it by 4, and the remainder is your answer instead of the quotient. So from my example we get:

6 mod 4 = 2

Now we have the first number out of 10 possible numbers for the first number in our combination. To get the remaining 9 numbers, add 4 and recording the answer. Now add 4 to the answer and keep repeating this cycle 8 times. For my example I get: 2, 6, 10, 14, 18, 22, 26, 30, 34 and 38. These numbers are all the possible numbers for the first number in the combination, and we have reduced it from a possible 40 (amount of numbers on the padlock dial face) down to 10.

To find the 10 possible numbers for the second number in your combination, simply add or subtract 2 to the set of numbers just found. If the first number in the set of numbers for the first number in your combination is a 0 or 1, than add 2, otherwise subtract 2. So, for my example I get 0, 4, 8, 12, 16, 20, 24, 28, 32 and 36.

So now we have 10 possible numbers for our first number in the combination, 10 possible numbers for our second number in the combination, and we know the third number. We have now reduced the possible combinations for our padlock from approximately 64,000 to 100. Now we simple try each 100 possible combinations until our lock opens. This usually takes less than 20 minutes.

Results:

Possibilities for First number: 2, 6, 10, 14, 18, 22, 26, 30, 34, 38


Possibilities for Second Number: 0, 4, 8, 12, 16, 20, 24, 28, 32, 36


Third Number: 6

My combination is 26 – 32 - 6