Sometimes it's a riddle - a seldom seen IWC Calibre

A while back I located and secured what I believed to be a fairly old (1890's)
pocket watch in the UK.

This movement has the serial number of 156765.

Using the Date your IWC utility this shows as a Calibre 53 from 1897.

But this is definately NOT a calibre 53

A Calibre 53 movement looks like this.

I looked through all my data and pictures here, and could not place it.
Neither is the movement listed in IWC Fournitures No. 7

So I reached out to Tonny, saying I had a movement that looked like a Cal. 57
Americaine but then in mirror image.

So I asked our forum moderator - could this be something I don't have in my
collection? He said look it's a Cal. 56 like mine and sent a picture.

Here is his Cal. 56 side by side with mine. In the photo although not
vissible, the stem are both orientated upwords.

So my c.56 on the left and Tonnys C.56 is on the right hand side here.Clearly
not the same - no?

flic.kr/p/2n4bh1m

So, the question to you all then, which one of us has a C.56 and if one of
these is a C.56 - then what is the other movement.

Maybe one of the 3 wise men will answer this riddle.

A true puzzler indeed.
I'm looking forward to reading of the adventure this one leads us on

who oh who has a C.56.

I say I do ... On the basis of this fact sheet here below.

So if mine is a C.56 then what is Tonny's ??????

Ahh Tonny, but this picture is no riddle - one of your two shown pieces
labeled Calibre 57 is in fact a so called C.57 Americain.

A known naming convention for this movement.

Here's mine.

Dear Mark,

I don't know, who the three wise men are, you refer to. But the movement you
show in your post starting this thread is a Cal. 57 in the old design, dating
from the mid to late 1890s.

There are four versions of the Cal. pair 56/58: Lepine (balance about 3 or 9)
and Savonnette (balance at six o'clock) in the new design with three screws on
the winding wheel and in the old design with two central screws on the winding
wheels.

Your movement has the two central screws on the winding wheel, is therefore
the old version. And it has the balance not at six, so a Lepine, so in terms
of calibre numbers a Cal. 57.

This calibre was pretty common for the UK market served by Stauffer, so no
wonder it bears the Stauffer trademark.

Best regards

Thomas

Many thanks for your detailed responce Thomas.

Do you have a picture of a "true" Cal.56 movement that you could share.

The one on the right looks like the C. 56 to me.

Dear all,

Cal. 56 is an ambiguous designation. Since the 1890s with alle calibre pairs
the lower number is the lepine, the higher number the savonnette, e.g. Cal. 52
Lepine, Cal. 53 Savonnette, Cal. 71 Lepine, Cal. 72 Savonnette.

With the Cal. 57 Lepine and its Savonnette twin the situation is a little bit
different. In the very early times of this calibre pair the Savonnette was
designated Cal. 56, but after some time renamed Cal. 58.

All the savonnettes in this thread are from the era they already figured as
Cal. 58. And indeed: If the crown is in the 12 o'clock position and the
balance in the 6 o'clock position it is a savonnette, so some calibres 58 in
this thread.

Regards

Th. Koenig

The Serie 156'601 to 157'200 is one of the entries in the Tolke list which is
wrong. This are c.57 19 lig (Mod. 1894)

regards

Ralph

An other sample of the same movement (but of a later serie 187'705)