ROLEX REFERENCE NUMBERS & CALIBERS
We receive many different Rolex watches for service. Most of the time our customers have no idea what the movement of their Rolex watch looks like and many time they don't know what Ref. Number their movement is. This is especially true of the older vintage Rolex watches commonly referred to as "Bubble Back." The "Bubble Back" term originated when Rolex produced watches with the Auto Wind mechanism. These watches were rather thick and the backs were very round and bubble shaped. Hence the term "Bubble Back".
We will start showing photographs of the different movements. We will also have a listing of the different Ref. Numbers and the dates they were produced. You will note that most watch companies refer to their movements by a caliber number. This is actually the model number of the movement. Rolex did not use the caliber reference system, but used their own Ref. Numbers. Ref. is short for reference. A typical Rolex number would be as follows. Ref. 720.
Rolex Ref. 2135 and 2130
These three photographs show the Rolex Ref. 2135 ladies Rolex that features the quick change date feature. This movement is very durable and is used in many popular ladies Rolex watches. The first pictures shows the movement after the automatic winding mechanism has been removed. The second picture shows the top of the winding mechanism along with the typical Rolex markings. Here you will see the reference number of this watch. The third picture shows the underside of the automatic winding mechanism. Here you can see the two reverser gears that drive the larger gold colored gear. This large gear drives the ratchet wheel which in turn winds the mainspring as the watch is being worn.
It is very important that your Rolex is properly serviced at regular intervals to insure that the automatic winding mechanism is functioning properly. During this service which should be performed every three to five years, a new mainspring should also be installed. This will guarantee that your Rolex has the ability to store the proper amount of reserve power. This reserve keeps your Rolex running during periods of inactivity.
The Rolex 2130 movement is essentially the same as the 2135 movement but does not have the quick set day date feature. Following are pictures of a typical ladies Rolex that has the 2130 movement. Notice that this Rolex is time only.
Rolex 2130 and 2135 Perpetual or Auto Wind Mechanism
The Rolex 2130 and 2135 movements both utilize the same perpetual mechanism to wind the mainspring as the watch is being worn. Each movement has an oscillating weight that rotates in both directions. Both movements contain 29 jewels many of which are located within the auto winding mechanism. Below are pictures of the perpetual winding mechanism that is found in both the 2130 and 2135 Rolex movements.
Note the markings which are normally covered by the oscillating weight. The markings show that the movement has 29 jewels and is adjusted to 5 positions and is also adjusted for temperature. The temperature adjustment is a function of the hairspring and balance. The beat rate per hour is 28,800. These pictures also show the two reverser gears that are driven by the oscillating weight. These gears are the two red colored gears. These two gears drive the large brass gear that is located between them. The large brass gear has a pinion which drives and winds the mainspring barrel thus supplying power to the movement of the watch.
The three pictures above show the 2130 and 2135 perpetual winding mechanism. The first picture shows the oscillating weight. Notice the oscillating weight arbor. This is very small and is only .59mm in diameter, yet it supports the entire oscillating weight. This small arbor is riveted into the weight. Special tools are used to install these arbor when replacement is necessary. It is very important that Rolex watches are serviced on a regular basis to prevent damage to these delicate parts.
The next two pictures show the oscillating weight after it has been installed into the winding mechanism. The pictures show the weight in two different positions as it is rotated. With every movement of your wrist this weight will rotate and operate the winding mechanism.
The above two pictures show the auto winding mechanism after it has been installed onto the movement of the watch. This particular watch was sent to us for service after the watch would no longer run. The oscillating weight arbor was broken and the weight was loose inside of the watch case. The movement was fully cleaned and properly lubricated and a new oscillating weight arbor was installed. This Rolex had not been serviced for over ten years. It is very important to follow a regular maintenance schedule and to have your Rolex serviced every 3 to 5 years in order to protect the precision Rolex movement and its 200 precision parts.
The following chart shows several different Rolex markings that are found inside of various cases and clasps. The "RM" is the Registered Mark along with the number that identifies the particular design.