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Slave clock


John Haine
 

Would anyone happen to have drawings for the standard 'Nome slave clock (the 1/2 minute impulse type) please?  In the Isaacs series in EIM on building a 'Nome he says he will describe a slave dial - did this ever happen?

Thanks all,

John.


Simon Taylor
 

Hi John,

The Synchronome ½ minutes clocks made for the GPO only differed in the resistance of the coil.
You may find the following links useful.



Simon GPO Clock





On 29 Mar 2019, at 17:29pm, John Haine <john.haine@...> wrote:

Would anyone happen to have drawings for the standard 'Nome slave clock (the 1/2 minute impulse type) please?  In the Isaacs series in EIM on building a 'Nome he says he will describe a slave dial - did this ever happen?

Thanks all,

John.


--
Simon GPO Clocks

http://www.lightstraw.co.uk/gpo/clocksystems/index.html


John Haine
 

Just to say that I now have the information I need, which was the module/tooth profile of the reduction gears used.

For reference, the module (at least of the initial 3:1 reduction from ratchet arbor to intermediate) is 0.5, the tooth counts being 15:45.  I was puzzled looking at the pinion that the profile looked more like an involute, but a 15t 20 degree PA involute pinion seems to mesh extremely well with the intermediate.  I assume that the other, 4:1 ratio, uses 12:48 teeth since the arbor spacing has to be the same.