Product Idea |

The Coded Cube


The coded cube


Last week my brain was strucked by lightning,

-how a fully functionable dial combination lock mechanism could be built in Lego. This question has stayed in the back of my head for years. And now it's finally real!

The lock built is in my opinion neat, thight, simple, strong and accurate. The door would definately not open if say the dial is set to 15, when it schould be at 17.

After the lock was completed, I made a simple and rather dull looking casing for the lock to spread it wings.


The case itself is firmly locked togheter from the inside. It's impossible to take the it apart unless the door is open.


The lock works as follows:


Open a closed and locked door:

  1. Turn dial CCW until stops.
  2. Turn CW 360deg.
  3. Turn CW to first Number (45).
  4. Turn CCW 360deg.
  5. Turn CCW to second Number (17).
  6. Turn CW to third Number (40).
  7. Push down and pull handle.

(Numbers are fixed).


Closing and locking an open door:

  1. Push door closed (self latching).
  2. Turn dial wherever.


There is a total of 3 ways to get the safe open:

  1. Unlock the normal way as explained above (preferred).
  2. Unlock the secret way if the code sheet is lost (preferred if code sheet is lost, and you remember how to unlock the secret way). Small rebuild of lock needed.
  3. Unlock by using a saw or a hammer (only preferred if everything is a mess, and it contains a serious amount of real gold and diamonds you really need).


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