Portable Sun Dial

prusaprinters

<p>Based on a description in an old (1984) education magazine I build a virtual replica of a portable sun dial which was inspired by medieval portable sundial from Canterbury.<br/> What I originally planned to do was make a temporal or 12-hour sun dail making it a decorative object only. This is a sun dial for modern equal hours, the example is for 52 degrees latitude, northern hemisphere. The OpenScad file is included and be set for different north-south positions.<br/> I tried to base the dimensions on proper calculations, but couldn't get it right. It looks like the original, so I did something right :-). A smarter person than me may find the proper solution.</p> <p>Usage:<br/> The object requires a thin pole stuck through the proper month hole (roman numerals) until it reaches the opposite hole. Then orient the pole to the direction of the sun, so a vertical shadow appears. The end of the pole shadow should indicate the natural hour.</p> <p>If the weather improves, I'll add real live images :-).</p> <p>Source:<br/> The original inspiring article appeared in "BulkBoek JAARGANG 13/NR 143 from 1984". It was a special on "School Subjects in Midieval Perspective". The drawing is from J.A.F. de Rijk. <a href="https://www.bulkboek.nl/">https://www.bulkboek.nl/</a></p> <p><a href="https://en.wikipedia.org/wiki/Sun_dial#Vertical_sundials">https://en.wikipedia.org/wiki/Sun_dial#Vertical_sundials</a></p> <p><a href="https://en.wikipedia.org/wiki/Solar_zenith_angle">https://en.wikipedia.org/wiki/Solar_zenith_angle</a></p> <p><a href="https://en.wikipedia.org/wiki/Position_of_the_Sun#Declination_of_the_Sun_as_seen_from_Earth">https://en.wikipedia.org/wiki/Position_of_the_Sun#Declination_of_the_Sun_as_seen_from_Earth</a></p> <h3>Print instructions</h3><p>The four parts for the sides of a short pillar, and should be kept in place with the top and bottom (red).</p> <p>The pole of 112 mm should be about 1.5 mm.</p> <p>A "M600" filament change was inserted before the second last layer.</p> <p>The panels tend to warp after printing, so I used some glue in the middle.</p> <p>The original was intended with the MMU2 and printed upside down, but the results were less.</p> <p>Resolution: 0.15 mm layer, 0.4 mm nozzle</p> <p>Filament: PLA</p>