Clockmaker

Goal

You are at a clockmaker’s workbench. On the pin plate, a motor (a crank or a spring) is waiting to be wound. Place gears from the drawer on the pins to link the motor to the outputs: when the motor runs, the dial’s hands must show exactly the requested time, the automaton must make the right number of turns in the right direction, the cuckoo must call the right number of times and the chime must play the right number of notes.

How to play

• Tap a wheel in the drawer, then a pin: the wheel goes on it. Two wheels mesh when their teeth touch exactly; the pins where the chosen wheel would mesh are marked with a gold dot.
• Two meshed wheels turn in opposite directions, with the ratio of their teeth: an 8-tooth wheel driven by a 24-tooth wheel turns three times while the other turns once.
• A compound wheel is two wheels on the same arbor, a brass one at the back and a blued steel one at the front: they turn together. Only wheels on the same layer mesh with each other.
• Overlapping wheels, a wheel covering a pin in use, or a closed loop such as a triangle (three wheels meshing in pairs) jam the mechanism: they are circled in red.
• Tap one of your wheels to remove it. The Wind up button runs the motor and shows the result; you can try again as often as you like.
• Keyboard: arrows to choose a pin, digits to choose a wheel from the drawer, Enter to place or remove, R to wind up, U to undo, H for a hint.

Stars

The solver knows the minimum number of wheels for each mechanism. Three stars with that minimum, two with one extra wheel, one beyond. The progressive hint first shows the useful pin, then the wheel to put there, then places it for you; from the second hint on, the mechanism is worth at most two stars.

Modes

• Solo: the campaign of five workbenches (First Wheels, Reverse Turn, Compound Wheels and Gearing, Several Dials at Once, Masterpiece) of eight mechanisms each, free play in five difficulties and the daily mechanism, the same for everyone.
• Race the clockmaker: you and the clockmaker build the same mechanism; her copy comes together before your eyes. The first working mechanism wins. Five levels, from Beginner to Master.
• Two-player duel: on the same device, each player in turn builds the same mechanism. More stars wins, then the shorter time.
• Online: a race against the clock on the same mechanism.

Levels

The five free play difficulties range from a single dial with two wheels to mechanisms with two outputs, compound wheels, fixed parts and obstacles. Every mechanism is generated and then checked by the solver, which guarantees a solution.