Here is a working clock!

The hands move like a real clock. The idea is original from Joe Nagata. 
I build a smaller working version that does not have a RCX to control the clock.

Klok_parts.jpg is a list of the parts need to build the clock. (numbers refer to the quantity)
Below is the explanation for a series of exploded views to show you how to build this clock.
The most important part is a dark gray cam wheel (16), it can rotate freely round an axle.
The steps are shown in reverse order, so you'll need to work from the bottom of the page upwards.

The clock is not entirely accurate, it has a deviation of 1 second every 3 minutes.
To create a more accurate clock, you can use the mindstorms RCX,

To set the time on the clock, turn off power to the clock, remove the vertical worm gear and turn the
large, 40-tooth gear until you've reached the desired time setting. Then replace the worm gear and turn
the clock on.



EXPLODED VIEW
==============
Step 1 and 2

The motor axle has a half-bush (small pulley) on the end to drive the clock.
Connect the motor to the medium pulley (on the axle pin) with a rubber band,
then connect the small pulley on the end of the pin to the medium pulley on the length-6 axle.


Step 3

Notice the 1x2 Technic Brick with TWO (2) holes.


Picture A

If you do not have the darkgrey clutch gear, you can use this design:
Replace the 8-length axle and black clock hands with this unit , keeping the 8-tooth and 16-tooth gears,
placing them onto the end of this length-10 axle, in the same manner as shown in step 4.
With this design, the clock hands are axles instead of plates.


Step 4 and 5

The length-8 axle has a free-moving gear (16-tooth, dark gray) on the front and an 8-tooth and 16-tooth
gear on the end. An additional 16-tooth gear is visible that is attached by an axle pin to a Technic 1x2 Brick with two holes.
Be sure when building these steps that the length-8 axle can turn freely.
The hours hand is a 1x4 plate with small teeth at each end, that connects to the free-moving 16-tooth gear.
The length-4 axle that protrudes from the front of the clock can be replaced with a length-3 axle , but the
design shown here proves to be a more stable one. If you don't have the dark gray 16-tooth gear available,
a substitute design is presented below as Picture A.


Step 6 and 7

These are the last two steps.
The worm gear in step 6 will fit over the vertical axle (from step 2).


PLAY ON  (enjoy this clock on your desk :-)


Martyn[underscore]Boogaarts@hotmail[dot]com