MST 157 
Ligne13'''

Remarks: Meyer and Studeli SA (MST) had been in business since 1888, mostly producing cylinder movements. This is the first known ROAMER wrist watch calibre, featuring a jeweled Swiss lever, compensated balance, and three finger train bridge. The hallmarks date this movement to 1918. It is not identified in the available Roamer documentation, but most major features: train pivots; balance cock; barrel, crown, ratchet centers; dial pins; and lever, line up precisely with the MST175 along with signed dials. However, it exhibits a much more traditional sinuous Swiss bridge design than the later MST 175. Differences include the bridge design, many of the plate screws, and the setting and motion works (due to the centre pin clutch rather than a cannon pinon clutch). One final comment on the setting works, the design is very similar to that in the smaller, later calibres: the 202; 251; and 253, it also bears a resemblance to the 18 ligne 154 and the 19 ligne 195. The family resemblance can be no coincidence. The 13 jewels are in the normal places, except the lever piviot isn't jeweled (which would bring it to 15). The movement is unsigned.
 
I had initially hoped to match the movement to calibre number by finding a close match based on mainspring or staff size. However - the only early calibres from the 12-14 ligne range are some 12.5 ligne clyinder movements numbered 41, 49, 59, 60 and 91. To list it on this site I need a calibre number, and as the number is lost in the mists of time I have arbitarily decided on MST 157. There is a little logic behind this, based on the number ranges used and where the gaps are.
 
Production period: 1916-18

Jewels: 13
Beat: 18000
Winding: manual
Manufacturer: MST
Hand sizes:
Hour:-
Minute: -
Second: -
  
Stem tap size: -

Variant:
MST 157 13''' (28.9mm) sub second, 3 finger bridge

Common parts/Interchange
Balance Staff:
MST part number:-,  interchanges with MST: -
Mainspring:
MST part number:- interchanges with MST: -
Strength: -
Height: -
Length: -
Watches in my collection with the MST157:

All text and images are either © Kris Bubendorfer 2011-15 or © Roamer Watch Company.