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Modifying the clocks

A clock before treatment. Open the case using a screwdriver. Push it from the front between the snaplocks. The bending of the clear plastic outwards should be kept to a minimum; push the black plastic hook inwards instead. front view
rear view Even before lifting the lid you can clearly see the construction. Open the clock in this attitude, because...
...The gear for setting the clock is secured, but once the lid is off, only gravity is keeping the other parts in position. opened
first gear and seconds hand out Remove the first gear and the gear/shaft of the seconds hand.
Take the stepping motor plus subframe and PCB out of the case; they form a single part. Cut the copper foil between the chip (black lump) and the right coil contact using a small dentist's drill or a sharp knife. Solder two thin isolated wires (about 5 inches long) onto the coil contacts. Be careful not to disconnect the coil wires. There is no need to use different colors: the coil has no plus or minus side, the direction in which the stepping motor rotates is mechanically determined.
Next to the subframe you see the gear of the hour hand, in its original form and with its shaft shortened. Cut off 5 mm, using a sharp knife. Now when you put the clock back together, only the shaft of the minute hand will visibly protrude from the case, so you can securely attach the robot's wheels.
subframe
gears and contacts The case with the hour hand gear back in place. Next to it you see the minute hand gear, the wheel driving the hour hand, and the two battery contacts. All but the minute hand gear can be deligated to the bitbox. The robot doesn't need them.
Drill a 3 mm (0.12") hole in the clear plastic lid, for passing the wires. The hole should be near the coil. Put the clock back together. Check its mechanical operation, by temporarily attaching the seconds hand and turning it carefully. Saw off the battery compartment using a metal saw. The photo shows the final result. Only the minute hand shaft visibly protrudes from the case. final result

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