This is a mechanical clock that can help you explain time and clocks to kids.
Everything is held together with #6 flat head sheet metal screws.
5x 1/2" long
1x 1.25" long
The numbers are raised. You can pause a print at a specific layer height in your slicer. Then you can change the material in your printer, and un-pause it. I let the printer do one layer of the numbers (and border) in blue, and then switched to green.
This guy explains it well.
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