GoKawiilBack in 2019, I built a simple voltmeter clock:
The clock, version 1.
As the name implies, these clocks use analog panel voltmeters instead of traditional clock faces to display time. I didn’t come up with the idea, so I never really blogged about the design; I just built one and kept it on my office desk.
The idea endures, but most of the designs I see on the internet are needlessly complicated and not all that pretty, so when I decided to build a revised design, I figured it might be good to document it better. The process started with a rough mockup in a 3D design program:
A mockup of the new design in Rhino3D.
For this version of the meter clock, I opted to use three generic, 90° panel voltmeters from Amazon (link, about $9). I disassembled them, took careful measurements of the faces, and then printed replacement decals on adhesive paper. Printable PDF templates can be found here.
Customizing 5 V panel meters.
Note that the new hour gauge has 13 divisions, from 0 to 12, while the minute and second templates have 61 divisions, from 00 to 60. This is because I wanted to implement continuous motion for each hand; this meant that at 11:30, the hour dial couldn’t be just stuck at 11; it needed to be moving toward the twelfth division, even if it was never to reach it.
In addition to a host of other problems, the cheap “Baomain 65C5” meters I’m using have a rather hideous plastic flange. I decided to hide this flange from view and use a recessed decorative pattern to keep the front panel interesting. This made it more expedient to cut the front and back on a CNC mill instead of building the enclosure by hand (as I did for version 1):
Machined front and back faces.
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