| The caliber 157 [message #422] |
Fri, 31 May 2013 04:04  |
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JackW
Messages: 1931
Registered: May 2013
Location: Denver
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This is the caliber 157 and is a 15 jewel movement that is 8-3/4 x 12 ligne or 19.4mm x 27.07mm. This is one of the Quadron movements and is the only one that is 15 jewels. These are clearly marked with a caliber number often on the pillar plate next to the escape wheel.
There are two variation: One is a 'reduced' barrel bridge design and the other is a single train-bridge without the separate 'finger' for the escape wheel. Also, these movement appear with a frequency in Alpina marked watches. These can be marked 157 but also 765. An example here of a reduced barrel bridge.
These will also appear in Gubelin marked watches, and still noted as a 157.
A major difference in the Alpina and the Gruen editions of these movements is that the Gruen use a Breguet overcoiled hairspring where as the Alpina's use a flat hairspring.
patent is HERE
All I know is based on hard work & writing by others. I can only aspire to augment this body of knowledge. If I am wrong it is because of my own failings. -me
"If I have seen farther it is by standing on the shoulders of giants." - Newton
[Updated on: Tue, 25 June 2013 14:36] Report message to a moderator |
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