Following this manual you will set a passcode on Ugears Safe

By default, the Ugears Safe assembles with a standard combination lock code (4 of them are pointed in the manual). To set another code, while assembling, you will need to replace the pegs #48 and #49 located in three huge washers labeled 40, 41 and 42 into the slots with other numbers.  How to make your own safe lock combination, to find out the right digits for the pegs and to put your personal code during the assembly? It’s quite easy to do, solving a math exercise.

 

Let’s suppose you would like to put the code  416:

A=4, B=1, C=6

The Formula for setting plugs in the discs:

a) P2 = P3 – ((B – A + 8) mod 10)

b) P1 = P2 + (B – C) mod 10

where A, B and C are the digits of the wanted code.

For technical reasons, C can only be 1, 2, 6 or 7

P1, P2, P3 – plugs in the discs. For technical reasons, P3 – P2 ≠ 4

E.g. let’s find P1, P2, P3 for the wanted code 416:

Number 1

Complete formula a) step by step:

P2 = P3 – ((B – A + 8) mod 10)

P2 = P3 – ((1 – 4 + 8) mod 10)

P2 = P3 – (5 mod 10)

P2 = P3 – 5

If you don’t now ‘mod 10’, than just go to Google an type ‘5 mod 10’ and Google will tell you. Though we believe that you know the ‘mod’ function.

 

Number 2

Set in valid values, there are many possible solutions. Just choose one with P2 and P3 being 0 to 9

P2 = P3 – 5

with P3 = 5, P2 is 0

with P3 = 8, P2 is 3

 

Number 3

Solve formula b) with the first of the possible combinations

We will use P3: 5 and P2: 0

P1 = (P2 + B – C) mod 10

P1 = (0 + 1 – 6) mod 10

P1 = -5 mod 10

P1 = 5

again: Google will tell you, that “-5 mod 10” is 5, just don’t think about what this means :-). Though we believe that you know the solution.

Solve formula b) with the last of the possible combinations:

We will use P3: 8 and P2: 3

P1 = (P2 + B – C) mod 10

P1 = (3 + 1 – 6) mod 10

P1 = -2 mod 10

P1 = 8

Again: Google will tell you, that -2 mod 10 is 8, just don’t think about what this means 🙂 Though we believe that you know the solution.

So: for 416, use 838 or 505 for plugs in the discs.

Last, but not least, make sure to set the parts together the right way – as told in the manual. C is important when the wheels are put into the safe (For technical reasons, C can only be 1, 2, 6 or 7)

In case of emergency opening or if you forget your opening code you can make slow knob twists and carefully listening to tumbler movements that will open the lock (twist left to the first digit via 0, then twist right to the second digit via 0 and then twist the knop left again to the third digit via 0). Listen carefully every time and stop twisting on a digit when a click will be the loudest.  If the combination is correct, your safe will click and open itself on the third digit).