In other words, you have to disassemble the watch to access it.Later on, the serial was always on one of the bridges.

The edge on the rotor will have an obvious loss of plating. The inner side of the case back will have a characteristic circular trace on it. However, if one part has an almost yellow gold color, and the other one has a deep, dark copper tone, you can be sure they didn’t leave the factory together.

Another example of frankenising is using parts from Tissot counterparts in movements, which the two brands shared. I’ve seen rotors from the Tissot transplanted in an Omega.

Of course, you’ll have to do an awful lot of research on your own.

In this part of the identification guide for vintage Omega watches, we’ll focus on the movements.

The one thing that’s known to go wrong with these movements is the axle of the rotor. You can often spot them by an inconsistent tone of the plating throughout the various components. As long as you follow the basic rules of identifying the movement, and you keep the possible issues that are mentioned above in mind, you’re in the clear.

When it wears out, the rotor will start rubbing against the bridge on which it sits (upper bridge for automatic device), and against the case back. Of course, some parts will change color due to the different solutions they were cleaned in during a service. If you see a 60X series movement in a case with a reference that tells you it’s a model which is supposed to be equipped with a 5XX-series automatic, that’s obviously wrong. The 321 is always marked as such and always has copper-colored plating.Until the 1990s, the only supplier of chronograph movements for Omega was Lemania. So, if you’re checking out an Omega chronograph from the 1950s, which is supposed to have a cal.The movements were also constructed to a view with providing great durability and accuracy and were produced in various iterations – one of the highest grade versions of the 19‴ caliber was fitted with, in addition to a bimetallic balance and blued steel overcoil balance spring, a snail-cam fine regulator, and 19‴ movements would go on to become leading performers in their category in the Observatory time trials.The movements were also fitted with a patented mechanism allowing both hand-winding and hand-setting of the time from the crown.I’ve encountered cases, where a dial signed “Chronometre Omega” was fitted to a non-RG 30mm movement. A non-RG 30mm movement a “chronometre” dial = frankenwatch. This is nothing more than a 5XX base without the automatic winding assembly. They were mostly used in the Geneve collection, however, a few Seamaster De Ville models had it as well.