Unlike other wooden combination lock you can find on youtube, this model uses only the input disc to lock/unlock the mechanism, without additional lever that should be moved once the combination is set. This is exactly the mechanism you can find in a safe. In the same way, it's not possible to unlock the mechanism if you don't know the combination!
I developed the original scheme found on internet with 3D Sketchup. The result is converted into code for my homemade cnc machine.