Having always been fascinated by POV displays i figured it would be interesting to switch it around and having a reflector spinning instead. the first iteration had numbers printed on a disc and the idea was to have a LED blink when the desired number was visible in a small cutout. That way it would be more like a digital clock.
But I thought it would look better more like an analog clock with arms and I figured I could use different colors for the arms.
Which worked out nicely.
So using a HDD motor and a HDD platter as the spinning part ensured it would be fairly well balanced, since needs to spin in several thousand RPM to avoid flickering. Because the position of the arms is calculated each rotation, the clock works from low RPMs up to around 10k RPMs.
The harddrive motor controller was found on ebay, and I believe it was this one: https://www.ebay.com/itm/DC-5V-12V-Brushless-Driver-Board-Controller-For-Hard-Drive-Motor-3-4-Wire-New/323120603788?hash=item4b3b7d228c:g:IJUAAOSw5vdanie7
The board controlling the LEDs was made my very first attempt at PCB design in KiCAD and it was based around scrapped reels of components found at work.
Taking pictures of the clock in action was a little bit tricky with all the light washing out the arms.