Introduction: How to Crack a Masterlock Padlock.
This little instructable will demonstrate how to narrow down the possible combinations for your lock from over 60,000 to 80. This is good for if you lose "your" combination.
Step 1: Knowing Thy Lock.
Before you find your numbers, you must know a few things about your lock.
First of all, there is a dial, a body, and a clasp (The U shaped thing on the top that comes out when unlocked).
When you open your lock you would normally spin the dial right a few times to reset, then go to your first number. Then, you would turn left, passing your first number once, then stopping on your second number. Finally, you would turn right again to your third, and final number and pull on clasp.
Okay, now you know thy lock.
Step 2: Finding Your Third Number
First, you must find your 3rd number of 3. To do this, turn right a few times to reset, then go to 0 on the dial. pull hard on the clasp and turn left a little until you notice your dial only turns within a little space. Now, you will need to use your brain cells to figure out the number in the middle. For instance, if the dial were stuck between 3 and 4, the number would be 3.5. Once you have your middle number written down, release the clasp, and turn left one number and pull again and turn more until you are stuck in another groove. Write down the number in the middle of the space. Repeat this process until you get 12 numbers. Not 8; 12. Okay? Your list might look like this:
So what you do, is take your pencil and cross out all the numbers with decimals (.5, .25, .75)
now you should have 5 numbers. If not, you didn't use enough brain cells to get the right middle number. Try again. But if you do have 5, you will notice 4 of the 5 end in the same number. Cross these out to. That should leave one number. In the case of the list above, that number would be 19.
That final-left number, is your third number.
Step 3: Finding Your First Number.
Okay. Now that you have you third number, it's time to get your first. Take your third number and divide it by four. Take the remainder. In our example our 3rd is 19 so we divide by 4 and keep the remainder. In this case, it would be 3. Hard? No. Now take your remainder ( Either 0,1,2, or 3) and write it down. now add 4. now write that down. Now add 4 to That new number. wright it down. Keep doing this pattern until you have 10 numbers down. Now stop. These are all the possible first numbers. Hooray!
19/4 = 4 R3(remainder)
3 + 4 = 7
7 + 4 = 11
3,7,11,15,19,23,27,31,35, and 39
Step 4: Finding Your Second Number.
Mmmkay. Now think way back 5 minutes ago and try to remember that little remainder. If its a 0 or a 1, add 2 , if its a 2 or a 3 subtract two. Now add 4. Write down. Do that 9 more times. Good job. Now take away any numbers +/- 2 from your third number. Now you have all the possible numbers for your second number.
Remainder = 3
3 - 2 = 1
1,5,9,13,25,29,33, and 37
Step 5: Narrowing It Down Even More.
Okay. Now you should have 10 1st numbers, 10 2nd numbers, and 1 third number.
Now remove any 2nd numbers +/- 2 from your third. Wallah! you know have narrowed it down by 20 poss. combinations.
Step 6: Finding the Right One
Now take your numbers and make a table and try out all the diff combos and cross them off if they don't work, so you can remember.
P.S. This may not work on older models and ones with locks in back.(Haven't tried any of those yet)