Some manufacturers produced many different movements with the same basic layout and identical train and keyless work components, but with different patterns of cocks and bridges.
Fabrique Horlogerie Fontainemelon (FHF) was a large manufacturer of Swiss ébauches who did this a lot.
In fact, the apparently huge variety of Swiss watches is explained by this phenomenon: once the basic layout in a round movement of the barrel, train wheels, escapement and balance was arrived at, there was little scope, let alone need, to change it.
To see a clear example of this look at the section below about Eterna movements customised for Stauffer & Co.
Compare the bridge shapes shown in Jobin for the Eterna movements and those seen on Stauffer branded Eterna movements.
Contents Measuring Movements Photographing Movements BTCo: Beguelin, Damas Longines 13.34 Longines 12.92 Gallet Electa wrist Gallet Electa pocket IWC calibres 63 and 64 Stauffer Eterna Tavannes cal 330 - 333 Tavannes cal 370 - 371 Fontainemelon 1 Fontainemelon 2 Fontainemelon 3 Fontainemelon 4 Fontainemelon 5 Fontainemelon 6 A. Schild calibre 168 Early Omega Wristwatch General Watch, Helvetia Marvin series 362 Dimier Brothers Mystery movement 1 Mystery movement 2 Manzoni Arogno A Michel Cal.
220 It is a small selection of often unidentified old movements that I have been able to positively identify.
This has an integrated detent spring which holds the setting lever in either the winding or setting position.
This cover is called the "setting lever spring" in Swiss parts lists, with the generic part No. The other two parts shown are the setting lever and the yoke that moves the sliding pinion.
Stem set keyless work needs a detent to hold the crown in the winding or setting position.
In early stem wound and set watches the usual Swiss "positive" set keyless work (in contrast to American or negative set) incorporates this detent as part of the mechanism, usually a notch on the yoke, whereas in later watches it is integrated into the cover plate as in this watch.
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