WatchTech - Setting up the equation wheel

Setting up the equation wheel

Aug 31, 2015,18:59 PM

Is it difficult for David to set up the equation wheel? With this style of equation mechanism, from my knowledge,
the most complex, I know the positioning of the quadrants on the equation gear dictates how far ahead or
behind the solar hand will be from the mean hand.

What I was wondering is, since the syncing of that hand to the actual equation needs to be accurate,
how difficult is it to set up the equation wheel assembly correctly?

Is it as simple as setting the quadrants to the middle of their motion, and then indexing the equation
kidney to one of the 4 days of the year when the net equation vs mean difference is zero, then setting
the mean and equation hands directly on top of one another when you put the hands on, and
then moving the date accordingly?

I have always wondered about this. It's a bit similar to setting up a perpetual calender mechanism-
there has to be some synchronization of components by the horologist to make things read correctly.
This message has been edited by Ophiuchus on 2015-08-31 19:00:53

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A David Walter Double Pendulum Clock – Part 9, The Equation Wheel

By: DonCorson : August 24th, 2015-12:08

A David Walter Double Pendulum Clock – Part 9, The Equation Wheel Every week we are seeing more of David's work on his new double pendulum clock. The equation wheel is one of the more esoteric pieces of the movement. Its purpose it to drive a minute hand ...

Setting up the equation wheel

By: Ophiuchus : August 31st, 2015-18:59

Setting the Equation

By: David Walter : September 4th, 2015-13:21

requires at least 1 reference point. If you look closely at the cam you will see there are 8 points marked. There are 4 days of the year when the days are equal and there are 4, plus or minus extremes. A way to set it up is to set the cam to one of the 4 ...

Ahh, makes sense

By: Ophiuchus : September 7th, 2015-07:52

So that little hole in the pipe coming off of the center of the equation cam meets one of 8 holes underneath drilled into the cam itself, around it's shaft, where you can quick insert a pin to lock the equation mechanism into one of the 8 equal or extreme...

Not quite how it is...

By: David Walter : September 7th, 2015-13:00

That hole on the upper end of the pipe is tapped to hold an annual date disc in position. The cam, year wheel, pipe and date disc once set when I make them are all screwed in position and can't be seperatly rotated. The equation hand is pegged so it too c...