Main purpose of clock dial is to seal hole and keep dust away from sensitive mechanical parts.
At first it was intended to be just a dust cover but, since whole device resembles a mechanical clock, I've added simplified hour marks to it.
Hour marks are milled using drill press converted into manual mill by adding x-y table.
Edge-lit technology applied to acrylic dial make it much more attractive (well, next model may include second edge-lit acrylic layer with engraved digits).
Dial is illuminated by 4 high intensity blue 3mm LEDs embedded into its sides.
Each LED is inserted into short slot and secured with hot glue.
All four LEDs are wired in series with resistor and connected to 12V circuit.
To achieve comfortable soft brightness, LEDs current is limited to 5mA by 470 Ohm resistor.
|Clock dial after milling.|
|Slot for 3 mm LED.|
|LED wired and secured with hot glue.|