Rolex DateJust Models
One of the most popular watches in the Rolex line is the Oyster Perpetual Datejust model that features a 26 jewel movement. The movement reference number of the following Rolex is 1570. The 1570 was first introduced in 1965 and is based on the 1530 movement which came out in 1957. These models are self winding and have the sweep second hand. The movement is shock protected and has a beat rate of 19,800 beats per hour. After 1972 these movements were equipped with a hack mechanism.
The above three pictures show a typical Rolex Datejust after restoration. This particular Rolex also had a new sapphire conversion crystal installed replacing the old plastic Cyclops crystal. The silver dial and hands were not refinished.
The first picture above shows the 1570 movement markings. The second picture shows the jewel markings along with the typical Rolex marks. The third pictures shows the exposed movement after the self winding mechanism has been removed. The self winding assembly is held in place with three blue colored screws. It should be noted that many of the 26 jewels in this movement are actually located within the self winding mechanism.
After the barrel bridge is removed as well as the balance wheel and bridge you can the large brass colored mainspring barrel. Just above the mainspring barrel is the center wheel. You can also see a very small pinion in the very center of the watch movement. This small pinion is what drives the sweep second hand. The center picture shows the barrel bridge. The third picture shows the movement after the mainspring barrel is removed. At this point the movement is then removed from the stainless steel case.
The first three pictures above show the balance wheel of the 1570 Rolex movement which is the heart of the watch. The 1570 as well as other models have a blue steel hairspring. The balance wheel is solid and has several screws that are used to adjust the timing of the watch. In the second picture you can see what is called a Micro Stella timing screw. A special tool is used to either move this screw in or out to adjust the speed of the balance wheel. Typically there are four of these special screws located at equal distances around the circumference of the balance wheel. Two of these screws are for major timing adjustments while the other two are for minor timing adjustments. Using a combination of all four screws one can adjust the Rolex movement to keep near perfect time. In the field it is usually not necessary to adjust these screws as these movement as well as other Rolex movements have been precision timed at the factory. You will also notice that the balance wheel as it is suspended from the balance tack hangs perfectly level. This is very important in order for the watch to keep time correctly.
The fourth picture shows a new Rolex white alloy mainspring in its factory collar. The mainspring is inserted into the mainspring barrel from this collar using a special inserting tool. The new mainspring is never taken out of this protective collar until it is inserted into the barrel. The blue colored collar is then discarded.
The Oyster Perpetual Datejust can also be found in early versions where the movement contained 18 jewels. Seven jewels are located in the rotor assembly. This produced a total jewel count of 25 jewels between the movement and the winding assembly. The early versions of the Datejust will often have dials that are marked 50M = 165Ft. These dials will also have the Rolex name as well the standard Oyster Perpetual Datejust wording. Above the six position on the dial you may also see the Officially Certified Chronometer markings. Following are some additional pictures of a Rolex with a design number of 6305-2.
The following pictures show the 6305 Stainless Steel case. The case back as well as the case are both marked with the Registered Design number.
The case on the 6305 arrived from the factory with the typical plastic crystal which also had the Cyclops lens over the date. The following two pictures show the case after a new sapphire conversion crystal has been installed.
The four pictures below show the exposed Rolex movement that is found in the early versions of the Datejust model. These pictures also show many of the jewels that are located in the perpetual winding mechanism.
The following pictures show the restored vintage Rolex 6305. The dial was not refinished in order to maintain its original appearance.