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 Index  Timepiece Archive, Categories  Archive: Watch Movements    Timepiece Market 
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Fig. 1

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Fig. 2

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Fig. 3

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Fig. 4

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Fig. 5

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Fig. 6

Revue 31 open face

stem wind and set
sub second

19''' / 16 size, Dm= 41.85mm, Do= 42.95mm
H= 6.6mm
F= 0.5mm
T= 2.6mm
7/15/16 jewels
f = 18000 A/h
power reserve 34h

Balance staff U312, Ronda 2406
balance collet 1.45mm
Ronda lists also the Ronda 4603 with 1.25mm, but this is likely so easy to get because nobody needs it.

movement section W1620
pendant section W1779, W1780

Mainspring / battery
2.80 x 17.0 x 0.18mm

1.80 x 1.10 / 0.26mm

Comments about the data

open face calibre
different bridge shapes (cf. also Revue 30 open face)
negative stem mechanism
lever cock and banking pins (examples) or lever bridge with fixed banking (cf. Revue 30)
Breguet hairspring (Fig.3, 5)
bimetallic screw balance (Fig.3)
cam disc regulator (Fig.3)

Example, year: signature; shock device
1-2) 1926: VWC (Vertex Watch Co.), Swiss Made, 7 Jewels - 855
3-4) ca. 1925: Prima, Swiss Made - 860
5-6) 1950: J.W. Benson, 62 & 64 Ludgate Hill, London, By. Warrant to H.M. the Late Queen Victoria, Swiss Made
(despite referring to Queen Victoria: 1950 is correct)

Not for Sale!
The movements presented in this caliber finder are not for sale. This is only a data sheet for identification and evaluation of the movement calibre, as well as for approximate dating.

bidfun-db 21.3 © 02-08-15, mtr-Ranfft

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