MST (Meyer und Stüdeli, later known under their brand name “Roamer”) is a swiss manufacturer, which started with cylinder movements, before they got known for their good quality pallet lever movements.
The MST 2 is a simple cylinder movement, probably made at the beginning of the last century, and it could not be identified with 100% certaincy, since it is not properly marked, but the hallhmarks “M” and “2” and the shape of the gear train bridge are a strong sign, that it is an MST caliber 2.
Ad you can see on the bast plate, the mostly jewel-free caliber (except the upper balance wheel bearing) is of rather simple quality.
The gear train is the standard of simple cylinder movements: The mainspring barrel directly drives the center minute wheel, followed by third and forth wheel (no possibility for showing indirect seconds) and finally the individually beared cylinder wheel.
The bearing cock for the cylinder wheel is grinded down, but it is not known, if this was already originally the case, or if it had to lose some height, so that the balance wheel after a change of the cylinder, does not grind on the cock.
What is certain, however, is, that the three leg cylinder anular balance is not shock protected, but their beating rate (probably 18000 A/h) can be adjusted with the help of a long regulator arm.
On the dial side you see the pretty modern rocking bar winding system and the ratchet, which consists of a well executed click spring.
At the 7 o’clock postition, there’s the balance wheel bearing, which consists of a simple meal bushing, which is covered with a metal plate. You can imagine, that this construction does not allow very good precision results.
|Number of jewels:||1|
Nickel anular balance|
|Balance bearing / direction hairspring:||Counterclockwise|
|Adjust mechanism:||Long regulator arm|
|Winding mechanism:||rocking bar winding system|
|Setting lever spring:||1 hole(s)|
|Size:||11 1/2''' (measured: 26,5mm)|