Astronomical Clock as described in Britten's handbook


  After Ferguson's design (1710-1776)



A clock showing the comparative motion of the heavenly bodies



Sun ball = local time
 First ball = winter time
Second ball = summer time
24 hour plate = divided in 29.5 Moon days

The Zodiac is the real Astronomical one, with different length of the signs



The pendulum rod is from Invar

 Calculation sheet 1
 Calculation sheet 2




Driving clock (with winding at the side)

For this clock I also used the book " How to make a weight driven 8 day wall clock by John Wilding"


Winding view from above
It has
strong Bevel gears, the pin in the front makes it possible to disengage


Epicyclic Wheelwork


Later I had to change the Bevel Gears, the turning direction of the Moon ball was wrong


At both ends of the shafts are miniature Ball Bearings
(Rex Swensen did a good research about the use of Ball Bearings in Clocks,
if washed out with a solvent the friction will be about 1/70 of a plain pivot)


The 24 hours disc with Sun


Some parts of the driving clock
The Barrel has at front and back side ball bearings to support the heavy Weight



Barrel (with maintaining power)


 Wheels and lantern pinions, the escape wheel is hand made



Rough lantern pinions - pin size 0.6mm
(Dressmaker pins, pressed in)


Winding Key


Click spring - click pivot - back cock - crutch


Back cock


Homemade depthing tool


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