This application will help you recover the combination
to your Master lock. By pulling up on the shackle (or
down on the lock if it is presently locked in something)
while turning the dial, you will find sticking points
that will tell you the last number in the combination.
The cam associated with the last number is the one that
spins with the dial and brings the others into proper 
alignment by the right-left-right (cw-ccw-cw) movement
of the dial (two turns, one turn, less-than-one turn.)

If you have an old style Master lock, there is only one
"sticking point." Turn the dial left and right to this
sticking point a few times. The number in the center of
this range of motion is the last number in your combination.
If you have such a lock, enter that number here and click
the "crack" button.  
If your Master lock is a newer model, it will have 12
sticking points,which you will enter into the 12 boxes below.
One of these points will be the actual last number in your
combination.  Turn the dial two turns
clockwise, stopping at zero. Create resistance to the dial's
movement by pulling up on the shackle or down on the body.
Turn the dial ccw (top to the "left") and note the first
place where the dial sticks. (apply more or less force to 
the shackle depending on whether you get "good sticks" or
not.) Continue turning ccw until the dial has made one 
complete revolution. It is OK to make side-to-side movements
to get a feel for the stickiness to verify a point. If the
point seems to be between two numbers rather than on a mark,
such as between 20 and 21, we'll call that a fractional
number - in this case 20.5. Each of the sticking point 
numbers will go into a box below. You should have found 12
spots where the dial stuck.

Enter the numbers below and click "crack"; the application
will determine the correct last number and display all 
possible valid combinations for that last number. The first
and second number possibilities are a function of the last
number. You will find that instead of 64000 (40*40*40) 
possible combinations, it is now narrowed down to 100
(showing that there are really only 4000 possible combinations.
sure there are 64000 variations in the way you can turn the
dial, but only 4000 (40*10*10) of those matter.  Since we've 
just found your last digit, that leaves only the 10*10 (100) 
possibilties. (You will find that if your last digit is odd, 
so will the 1st and 2nd be, likewise with even.) Due to the 
mod 4, (mod 4) + 2, arrangement of the other numbers, we're
left with only 10 possibilites for each the second and first
numbers of the combination. Enough already let's get cracking.
Enter the numbers in the 12 boxes below. Order is unimportant.