Lighted 3D Moon Phase Clock
Introduction: Lighted 3D Moon Phase Clock
In this Instructable, I will describe the design and build of a clock that shows the current phase of the moon in a lit 3D printed moon model. This project started this summer when I began to think about a project for my new 3D printer. I had printed accessories for the printer and chose a moon lamp (https://www.instructables.com/Moon-Lamp-With-Remote/) . I thought it would be nice if it could show the moon phases and saw in the comments someone else had the same thought. So I began thinking about a design and this is what I came up with. It was also an opportunity for myself to learn the basics of Fusion 360.
Some General Background
A simplified description of the lunar phase cycle will be used that is based on the average cycle of lunar phases, the synodic month. The synodic month averages 29.530588 days, but can actually vary between about 29.18 to about 29.93 days in any individual cycle, due to the elliptical orbits of the moon and the earth. This results in variations of up to seven hours about the average in any given year https://en.wikipedia.org/wiki/Lunar_month#Synodic_month. 411
The side of the moon facing the earth is gravitationally locked (tidal locking) so we see essentially one hemisphere of the moon from earth. In actuality, over time we see about 59% of the moon due to lunar libration. Libration from our perspective on earth is the slight top/bottom rotation (like nodding yes), left/right rotation (like nodding no) and tilting back and forth (like a metronome) of the moon resulting in an apparent wobble. This is due mostly to the eccentricity of the moons orbit and a slight tilt (6.7 degrees) of the moons rotation axis to its orbital plane, along with the earths tilt. See: https://en.wikipedia.org/wiki/Libration , https://moon.nasa.gov/moon-in-motion/moon-phases/#otp_our_wobbly_moon.
Lunar Libration and the variability of cycles will not be considered for this project.
An interesting additional note is the saros or eclipse cycle. The saros cycle is 223 synodic cycles, approximately 6585.3211 days, or 18 years, 11 days, 8 hours where the Sun, Earth and Moon return to approximately the same relative geometry. Note that this is not a perfect multiple of a year or the same time of day, so basically the positional relationships between the Earth, Sun, and Moon effectively do not ever repeat perfectly, but come pretty close on slightly longer than an 18 year cycle. See: https://en.wikipedia.org/wiki/Saros_(astronomy), https://eclipse.gsfc.nasa.gov/SEsaros/SEsaros.html
Supplies
Supplies:
High torque quartz clock movement with long shaft (28-29, or 31 mm) and accessories, metal I-shaft minute hand with step second hand drive.
Examples:
High Torque Quartz Clock Movement, 11/16" Maximum Dial Thickness - 101150 (28.5 mm, 1-1/8")
High Torque Clock Replacement Movement, Clock Movement Metal Clock Needle Kit,31MM Long (Cut off the plastic hanger)
High Torque Quartz Clock Movement Replacement Parts …(31 mm (1-1/ 5 inches))
High Torque I Shaft Hands Quartz DIY Wall Clock Movement Mechanism...4/5 in Max Dial Thickness, 1-1/5 in Total Length
Clock Movement Mechanism with 5 Different Pairs of Hands, High Torque Long Shaft Clock Movement Quartz
clock second hand (to use or obtain mounting pin from) or short piece 1.5 mm tube, minute and hour hands (if not printing your own)
Stainless steel rod, 1 mm diameter
Example:1mm x 200mm 304 Stainless Steel Round Rod, Metal Solid Shaft Rods Lathe Bar Stock ... 10pcs
PLA filament (white, black, plus you're choice)
Screws for mounting clock assembly (2x) #8 x 1/2" sheet metal
M1.4 -2.5x6, 2.0 x3.0, x3.4, x3.8, x4.0 mm machine screws, eyeglass/watch screws
Example: Eyeglass Repair Kit
A few inches warm white ribbon LED (or small low voltage & wattage LED bulb with base) and matching wall transformer with appropriate DC voltage
Example: Olafus 16. 188