Ain't got no time for quartz clocks. Get that WWVB goodness. Boblobs's Modular Clock has a bunch of nice clock faces to choose from and is well thought out - it's just missing space for a better mechanism.

Vitamins

Remixed for HD-1688 Cheng Bang WWVB radio-controlled clock mechanism available:

• HR9412 on AliExpress for 12$
• HR9415+903 on Amazon for 20$ (same mechanism)

Printing & Assembly

1. Print a frame & face from the original Modular Clock. Print mount & hands from here.
2. I printed all these parts with 0.6 mm nozzle.
3. May have to shave down the interior diameter of a tiny bit with an x-acto.
4. Have your wife paint the second hand to a color of your choice; I matched Azure Blue from the marks.

Mods

• Clock hands increased size XY by 128% to better cover clock surface. Adjusted hole diameters to 5.13 mm for hour hand and 3.25 mm for minute hand.
• Cut out region inside “clockmount” for larger WWVB Radio mechanism.
• Added ribs to compensate for subtracted region in “clockmount”
• Added fixed wall mount hole for #6 or #8 screw in “clockmount”

Notes

After getting the time signal is was about 4 seconds slow of true. Compare to my radio-controlled Casio in the photo which was about 3 seconds fast.

Filament in images:

• Prusament Galaxy Silver PLA for “hands”.
• Prusament Urban Grey PETG for “clockmount”.
• Tecbears Silk Gold PLA+ for “circle frame”.
• Fusion Filament Nuclear Winter White HTPLA+ & Prusament Azure Blue PLA for “marks” clock face.

This is a good design, but with my silk filament on the frame I can see ghosting from the internal screw mechanism. If I were to redesign the clock face I would omit the screw mechanism and perhaps just use an M3 screw to hold the face in the correct position.