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Hello All;

I managed to get a NOS Molnija Pocket watch from a collector who passed away.

Before I do this relative simple walkthrough, I read up on this iconic Russian pocket-watch and like to share some of its history I gathered;

The Molnija movement is basically a copy of a Swiss cal.616 movement designed by Cortébert.

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This design was very popular and turned out to be a blueprint for many other movement designs such as in Rolex watches from around 1940's:

rolex-1940.jpg.393e75cc748b329180d0fe12b6bab7c4.jpg

The Molnija (Молния) pocket watches were made from November 1947 to October 2007. The main factory was located in the Ural town of Chelyabinsk with a second factory outside of Moscow. The Russian word Молния means "lightning".  The Russians improved accuracy of the movement quite a bit when they upgraded it to their 18 jewels version of the movement but the basic design remained the same until the closure of the factory in 2007. In other words the Molnija movement was originally a Swiss Cortébert movement. A high quality movement.

The movement is mainly made out of a nickel copper alloy. The smaller and more delicate cog wheels are made of brass and the bigger wheels which are directly connected to the main spring are made out of carbon steel.

 

 

Molnija technical specifications

 

Movement diameter: 36 mm

Movement types: early movements are called "ЧК-6" (ChK-6) and they have a nice striped pattern finish (Geneva stripes). Around 1964 a new movement called 3602 was introduced. The 3602 is almost identical to the "ЧК-6" but it has no finishing pattern and some of the internal dimensions are different such that you can not exchange parts between the two types. The 3603 movement is a 3602 movement with shock protection (the balance wheel jewels are different).

Jewels (gemstone bearings): normally 15 on the "ЧК-6" and 18 on the 3602/3603 movements

Rate: 2.5Hz, 5 beats per second, 18000 bph (beats per hour), Lifting angle 52 degrees.

Main-spring reserve: The watch runs about 40 hours when fully wound.

Balance staff: riveted, note "ЧК-6" (ChK-6) and 3602/3603 movements require different staffs.

Balance wheel: The balance wheel alloy was changed and improved over the years. At least 3 different kinds of alloys with different colors in Molnija watches.

Hairspring material: Elinvar, hairspring form: Breguet overcoil for 3602/3603 and flat hairspring for ЧК-6

The Chelyabinsk Watch Factory used in the 60's and later sometimes this symbol of a watch showing 9 o'clock.

 

Shock protection for a mechanical watch indicates that the delicate pivots that hold the balance wheel are mounted in a spring suspension system. A shock resistant watch is supposed to survive falling from a height of 1 meter onto a horizontal hardwood surface without any damage to the balance wheel staffs. Most of the Molnija pocket watches are caliber 3602, without shock protection. Shock protection is highly recommended for wrist watches but rarely used for pocket watches especially older models. Pocket watches are more protected against shock if they are properly secured with a chain or some kind of string and carried in a pocket. A few pocket watch models in the late 80's and early 90's were caliber 3603. The 1980's models had a triangular metal piece holding the balance jewel and the later 1990's models had a star shaped metal piece with a round center hole. The 3603 Molnija movement (shock protection) is not seen very often but it can be easily identified because the regulator has two arms that can be moved and the jewel on the balance cock is held in place by a small metal piece sitting on top of the jewel. 

 

The watch I received had the more rare 3603 movement, and the solid Silverine case was, apart from some "drawer-wear, in a superb cosmetic condition. It has a Steam locomotive theme and is also called a "Railroad" watch. The finish on the stamped locomotive is done with a grey paint, which wears off in time. The paint on this watch had no wear to speak of.

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m-2.jpg.e73a9b7d9830d18633c77186abfaf842.jpg

 

Here a close up of the 3603 movement with a "star" shaped anti-shock spring, suggesting that this movement is from the early 1990's. Clearly, nobody has serviced this watch since it left the factory. It ran, but stopped.

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The movement is held in place by two case-screws and is removed via the front, so the front bezel and the glass have to be removed first.

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Removing the hands; I used some 0.2mm thick plastic to protect, in this case the plastic dial.

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Remove any residual tension in the mainspring by holding the crown, lifting the click and let the spring tension slowly escape via the crown. Once the tension is off, the winding-stem can be pulled by depressing in the stem-release button. Undo the two case screws and take the movement out via the front.

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The plastic dial has two dial feet, hold in place by two dial-screws on either side of the movement. Note the anti-shock for the balance wheel and the separate cap-stone for the escape-wheel.

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Started disassembling the keyless works;

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With the keyless works and cannon-pinion removed;

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Flipped the movement over;

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Removed the balance assembly. Clearly to see the dried and solidified oil on the inside of the top anti-shock. Also the "nine-o-clock" stamp of the Chelyabinsk Watch Factory, normally "hiding" under the balance wheel.

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The escape wheel cock and wheel-bridge removed;

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Next is the ratchet wheel, the click, crown-wheel (left hand screw!) and thereafter the whole train can be removed;

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Next is the barrel bridge and barrel

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The movement has now been fully stripped and ready for some thorough cleaning.

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Also the main-spring has to be cleaned & checked; I normally take it out by hand and wind it by hand. After some practice it's not hard to do; however never loose concentration while uncoiling or winding the spring though ! These springs LOVE their freedom !!

m-20.thumb.jpg.79598d2ef5aec88c42298ae851de9a3d.jpg

Cleaned and checked the spring, re-wound and oiled it. Make sure the springs "side-wings" engage in a special hole inside the barrel and place the lid correctly.

m-21.jpg.c30a358d37e3b27dfe6073be98b71aed.jpg

It is also a good idea to demagnetize each part before assembling. Magnetism can cause strange and "un-explainable" running behavior later on. Best is to "nip it in the butt" right from the beginning.

m-22.jpg.93f5e1eaaf537fb3da58c1a5d23e97c4.jpg

Since we are dealing with dried and solidified oil, each and every jewel has to be cleaned thoroughly with peg-wood. Even down to the smallest jewel hole has to be cleaned manually. Every pivot has to be checked and manually cleaned it required. Failure to do so, chances are that the watch doesn't run fine.

For removing the anti-shock star form spring, I'm using this drilled out and edge-shaped peg-wood. It works very well for me;

m-23.thumb.jpg.8ee8fd2aa100ef4ea67ce0202d3d26ee.jpg

After cleaning the anti-shock cap stones, I'm using Rodeco to support it for oiling. Once the oil is on, you pick the Rodeco up, turn it upside down and place the cap-stone in the waiting Chaton. Hold with your tweezers the top of the stone and pull the Rodeco off. When using a 5x magnification, this works as a treat for me.

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Same methode for the escape wheel cap stones;

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Also Redoco for holding the pallet-fork while oiling the stone-tips; (hmm ...... it's about time for some new Rodeco !)

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Assembling the watch is the reverse of the above.

After some adjustment the timegrapher produced the following picture;

5a6f267757412_MolnijaDD.PNG.4d1faba9d2e41c2a10d5933c6db6e510.PNG

I'll settle for that !

Hope you enjoyed this reading and that this walkthrough will benefit somebody, some day ;)

Roland.

 

 

 

 

Edited by Endeavor
  • Like 4
  • 4 weeks later...
Posted

Awesome walkthrough! Thank you for sharing and I love the tip on oiling jeweled cap stones!


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