Dear John, Many thanks for the follow-up. I now have a heap more questions!!
In your drawing you have half-hour dots and quarter-hour tick-marks. In the photographs, I can't see the tick-marks. Is that my poor eyesight or did these get lost as a budget-saving measure? Also in the drawing, you have the tick-marks aligned with the root of the gnomon but the hour-labels are aligned with the centre of the ring. Did you consider having the hour-labels aligned with the root of the gnomon? I wonder what the shadow looks like at 10:15am, say, when it strikes through the number 10 at an intriguing angle? This whole dial looks like a seriously tempting object to climb up! Did you do stiffness calculations on the gnomon to check whether someone could swing on it? Is the point where the gnomon meets its support in the same plane as the dial plate? As a theoretical exercise, marking out a dial that declines 45 degrees and is offset from the vertical 12 degrees is not a big deal for most readers of this list but... Actually fabricating the dial, gnomon-support and gnomon itself and then assembling these components with the correct orientation looks like a very big deal indeed! I should be interested to hear just what jigs and tools were used and what checks were made at the fabrication stage to ensure that all the components were correctly aligned. What metrology procedures were used? Do you have secret levelling screws and so on to make minor adjustments when installing the instrument on site? No doubt your article will give us some gory details! All the best Frank --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
