- Straight-edge: NOT a ruler, I need to find a nice (straight!) length of hardwood with no markings. I may cheat and use a steel yardstick.
- Compass: I have a nice Staedtler compass, but it will not be big enough for some of the arcs required. I may add a beam compass or experiment with cord. There may be clues in the references as to how large, shallow arcs were drawn in period.
- Dividers: I have a nice pair of dividers that may be useful in transferring measurements.
- Paper: 8 1/2 by 11 good quality drawing paper.
- Protractor: Cheating a bit here. I will demonstrate that I can construct a protractor before I start using a commercial one, but drawing out one by hand each time I need one seems excessive, unneeded and probably not what was done in period.
- Astronomical tables and measurements – These would have been available to an instrument maker in period.
- For drawings requiring excessive geometrical construction (climate plates for example), work will be done on a working copy and transferred to a clean copy.
- Hartmann, Georg. Hartmann’s Practika, English translation by John Lamprey, Classical Science Press, 2002
- Morrison, James. The Astrolabe, Janus, 2007
- Stoeffler, Johannes. Stoeffler’s Elucidatio – The Construction and Use of the Astrolabe, English translation by Alessandro Gunella and John Lamprey, Classical Science Press, 2007
Overall, based on astrolabes from Hartmann’s era.
- The Front:
- Show throne, mater and limb.
- Limb marked in hours as the class example is.
- Mater hollow should display traditional scale.
- The Back:
- Elevation scale.
- Zodiac Ring.
- Calendar Ring (offset).
- Unequal Hour lines.
- 7 and 12 shadow squares.
- Climate plates
- At least 5. Based on the standard set listed in Stoeffler. Adding a Pennsic Plate (40-58).
- 5 Degree intervals on both almucantar and azimuth lines.
- 18 degree twilight line.
- Unequal hour lines.
- Possibly the lunar houses if I get (more) ambitious.
- Drawn properly in gothic style, pointers to major stars.
- Zodiac ring
- Rules and alidade
- Drawn with proper scales.
- Both single and double rule.
- Alidade designed with sights.