[Wavytone]

Ok ... well take a very deep breath.

Do you know the basic maths - see for example the texts by Jan Meeus or Peter Duffet-Smith ? Even just a first order solution is going to be hard for you as it involves trigonometric series and you won't do that mechanically. I used to calculate ephemerides using these methods 30 years ago.

What accuracy do you require ?

The method used by Duffet-Smith will get you to +/- 1 minute. To do better you have to use Meeus' method and allow for parallax (ie an observer at the surface, not centre of the earth) and atmospheric refraction - both of which are not trivial.

This is the point of the Emerald Chronometer which uses the observers location and in addition it syncs to atomic time standards within milliseconds.

But yes I agree a fine mechanical clock is a beautiful thing and I'd love to own one, having been to Greenwich in the days when they had a full exhibit of clocks (long gone now tanks to bean counters).

PPS there is a specialist fine woodwork gallery in Leura which has some superb handmade wooden clocks - upwards of $10k apiece - if you're into this might be worthwhile displaying there.