Declination circle identifies roughly celestial latitude and goes from +90 to -90 and back around to +90. Ideally, this would have one degree divisions. With the 10 degree lines labeled. The size of these setting circles and the low power of the scope that will ride on it makes one degree markings excessive and likely too small to see. Even getting two degree divisions are probably sufficient.
The Right Ascension circle is celestial longitude and goes from 0H 00M to 23:59. Again eed a program that turns a rotary table by 10 degree intervals, at the .1" depth scribes a line towards the center of the circle and marks the Hour mark. If these were foot diameter setting circles as observatory telescopes used before stepper motors, having 10 minute, five minute and one minute dividers would be nice, but even 10 minute dividers might be useful. (I fantasize about some vernier measurement similar to old micrometers allowing finer reading.)
One other circle with lines is harder to explain. The polar axis points to the North Celestial Pole (roughly, Polaris). There is a latitude scale used to help you get this reasonably precise.
This is only one quarter of a circle. Even one degree dividers might be sufficient. In practice, getting perfect alignment on Polaris is difficult. Unless you are doing astrophotography, being a couple degrees off will seldom impair tracking for visual use unless you need it tracking for hours.
That bash script for hexagons was hard enough to debug that I am writing these circle cutters in C. I have not written C in a couple of years. This means a but of relearning. How do I compile subroutine libraries and link them using gcc? It will al come back once I pull out my trusty Kernighan & Ritchie.
UPDATE: This posting shows one foot diameter setting circles on an 82" reflector
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