MST (Meyer und Stüdeli, also known for their brand name “Roamer”) is a manufacturer, which still exists today. In their early times, they made simple cylinder movement, before they became famous for their very well made pallet lever movements.
Most probably in the 1930s and 1940s, this cylinder movement for ladies’ watches was made, at a time, where cylinder movements were considered already technically obsolete.
Except for the upper (visible!) balance wheel bearing, the MST 323 completely lacks ruby bearings.
The gear train of this pillar construction is standard: Mainspring barrel (with ratchet on the dial side), directly driven center minute wheel, third wheel, seconds wheel at 6 o’clock and finally a steel cylinder wheel.
Of course, the flat anular balance is not shock protected. On the visible side (on the movement side), its axle is beared in a ruby bearing with cap jewel, but on the base plate, it only has got a metal bushing with a steel cover. It is easy to understand, that you cannot expect good timing results with such a construction.
The inner side of the gear train bridge shows, that the MST 323 promises more, that it can hold: Visually, the gear train bridge should look, like there are two bridges, one for the mainspring barrel and one of the gear train. That is by no means the case, there’s only a small slot as an illusion.
As you can see, the MST 323 uses a rocking bar keyless works with ratchet on the dial side. The ratchet uses a well executed pawl.
At 8 o’clock, there’s the metal cap plate for the dial side balance wheel bearing. It causes, that metal runs on metal, resulting in high wear and bad precision.
|Number of jewels:||2|
Nickel anular balance|
|Balance bearing / direction hairspring:||Counterclockwise|
|Adjust mechanism:||Long regulator arm|
|Construction type:||pillar construction|
|Winding mechanism:||rocking bar winding system|
|Setting lever spring:||4 hole(s)|
|Functions:||hour, minute, decentral second|
|Size:||8 3/4''' (measured: 19,3mm)|
Flume: 1947 98|