Recent

Projects

Timepiece - Completed  November 2nd 2011


Brand:

Rolex

Model:

Gents Oyster Perpetual with date (AKA: “Big Bubble”)

Reference #:

6105/6155

Serial #:

903740 (circa 1952)

Movement:

Caliber A.296/745 Automatic

Metal:

Stainless Steel and Yellow Gold

Bracelet Style:

Jubilee (stamped link)

 

I recently completed a “mechanical” restoration of vintage Rolex Automatic wristwatch. I use the term “mechanical” because the focus of this project was not primarily cosmetic in nature. This watch came to me in pieces from another watchmaker who had attempted a “vintage restoration”. The base movement was together assembled along with boxes and containers of parts containing the rest of the watch. There are many people “repairing” watches out there that claim to “specialize” in vintage repair or restoration. This is rarely the case as this type of work generally consists of cleaning and oiling an old watch. In my book this does not constitute any level of vintage restoration unless the qualifier was “getting it to tick”. The 60 years of wear combined with the generous “fixing” performed by the previous individual and needless to say this watch was more or less a basket case.

Condition As Received

 

·         The minute wheel post was heavily worn on 2 sides. This was causing the setting area to bind resulting in unnecessary pressure on the setting components increasing wear in this area.

 

·         The gear train bound but the escapement was free. This was due to excessive wear between the pivots and bearings causing extra deep depthing of the gear teeth into the pinion leaves, jamming them up.

 

·         Dial had previously been repainted with not the best of results, but the customer wished to pass on getting the dial properly repainted and printed.

 

·         The hands were scratched and fit loose to the posts. The luminous material was very discolored but intact.

 

·         Case and bracelet had been poorly refinished.  This was evident by “overspray” of the polish into the satin areas and vice versa due to a poor prep work prior to put the metal to the wheel.  Excessive rounding of the edges of the center gold links told me a soft buff was used which only rounded the links even more.  Refinishing is an area where many people incorrectly feel they have done a good job when a particular area could be checked off in a box on paper without any other qualifier such as maintaining sharp edges.


 ·         The bracelet was quite worn from decades of use but in solid shape. One of the pins in the clasp was loose and would need retightening.

 

·         The case tube was an old style nickel that had just been put in new. As there isn’t a good way to remove this style of case tube intact a new case s/s case tube was installed in order to properly complete the refinish. My other reason for needing to remove the case tube is that I need insure the tube had been sealed properly. I did not have a lot of confidence in this previous installation based on the quality of the other work on the watch and since my name was on the final repair, I made sure it was done correctly.

 

·         The winding stem was generic but was severely damaged from a previous watchmaker using incorrect tools to secure it to the crown. There was a heavy amount of debris accumulated in the setting area from this damaged stem eating away at the mainplate, like a milling bit. Proper installation and care of a winding stem is one of the most basic things to learn in watch repair education and is used on virtually every modern watch.

 

·         The balance cock was noticeably bent up and twisted in toward the center of the movement. No loupe was necessary to see this hallmark of fine watchmaking!

 

·         The hairspring was also severely mangled. Beside the extreme damage to the body of the spring, the overcoil had an additional set of vertical bends put added to increase the height of the overcoil in order meet the incorrect height of the balance cock. This is the butterfly effect of untrained “watchmakers” attempting watch repair.

 

·         Metal shavings from the setting area were present in the escapement area. This just shows how much all aspects of a watch movement are connected well debris from the stem area are clogging up the escapement.

 

·         The upper pallet jewel was dirty. This was again just lack of a proper watchmaker. The residue on the jewel was simply a sign of poor cleaning methods and quality control inspection. Easy to remedy during a normal quality service.

 

·         The seconds pinion driving wheel was very crooked and had not been properly trued after installation.

 

·         The lower balance setting was dirty and had metal shaving from the setting area inside.

 

 

Overall condition of the movement is very dirty (by professional standards) and is in need of extensive service before running properly again.


Work Performed

 

 

Cosmetic work was kept to a minimum as the customer’s main focus was functionality due to the watches sentimental value.

 

I couldn’t help but polish and bevel the movement bridge screws to remove previous watchmaker damage. These were the worst screw in the watch and I could not leave them in such poor shape risking someone thinking they represented my work.  

 

The balance cock was straightened and aligned. Endshake of the balance staff was controlled. Unfortunately I did this during the estimate process before I had decided to document this repair.

The hairspring was reconstructed. The extra vertical bends were removed. The damage to the coils of the body of the spring was corrected as best possible. The terminal bend and overcoil were reformed to center the hairspring and help the hairspring “breathe” more evenly in accordance with original factory design. The hairspring collet was manually adjusted to correct the beat error. Again, a large portion of this was undertaken during the estimate process to see if the hairspring was even salvageable or if a replacement needed to be sourced. This regrettably lacks photographic evidence as well.

 

The minute wheel was mounted on the lathe for accuracy and bored to clean up the inside hole of the pinion which had damaged the post. This hole as then polished for smooth operation in the future.

 

The minute wheel post was also cut off and bored out on the lathe for optimal accuracy. A new minute wheel post was machined to fit the newly enlarged pinion hole and also polished.

 

The improper depthing of the minute wheel and cannon pinion was thus corrected and unnecessary drag and wear was alleviated when setting the time. This also resulted in lighter pressure in the area of the winding stem hubs during setting.

The mainplate was machined in 4 places to correct for excessive wear in the upper barrel pivot bearing surface, lower barrel pivot bearing surface, lower center wheel bearing surface and the minute wheel post. These bearing surfaces were originally machined directly from the mainplate and were not adjustable or replaceable. The wear to these components is quite common in watches that are run for too long between service as well as those suffering from improper service techniques.



Boring the upper barrel arbor bushing to size


Cutting the lower center wheel bushing to length


Worn minute wheel post prior to replacement

The mainplate was bored on the lathe to insure the proper alignment and accuracy of the machining work. Adjustable bronze bushings were manufactured and installed allowing for end-shake adjustment and tighter side-shake. This work up-righted the mainspring barrel and center wheel freeing up the gear train and allowing for a smoother power flow through the gear train to the escapement.

A broken case clamp screw was noticed in the mainplate rim. This was removed and the hole was re-tapped. Since this screw was missing and the holes were not in the best shape all 3 holes were tapped and fit with new screws to match.

The upper ratchet wheel hub was polished to reduce future wear and increase winding efficiency in this area.

A new generic winding stem was polished and installed to replace the damaged generic stem in the movement.






Modify Website

© 2000 - 2011 powered by
www.doteasy.com