Ressurected Vostok 2809 - Next steps?

[NigelTufnel]

Hi everyone,

This is my first complete watch movement tear down and re-assembly project.  I have a vintage Vostok 2809.  When I first got it the Timegrapher was awful.  Examining the escape I realized the pallet stones were loose in the fork.  The shellac had completely disintegrated.  If you are inclined to help, and I would be so grateful, I'll first post my immediate problem and then a description of work undertaken and not.

Thank you all in advance!

There's a lot of different things for me to try but first I wanted direction.

TL;DR

It's slow, but the positional error is weird.  Believe it or not these measurements are so much better than when I first got the watch! Face up (pls. ignore vibration in 3rd chart, that was me shaking the workbench):

 

Face down:

 

Work done:

• Complete disassembly, cleaning and re-lubrication
• Mainspring removed, cleaned, greased
• Pallet fork stones removed, replaced, adjusted
• Exit banking pin straightened (was pretty bent)
• Demagnetized (several times)

Not done: 

• Mainspring is original, not replaced
• Mainspring barrel cleaned and arbor lubricated but barrel not polished
• Pallet stones not lubricated yet
• None of the gears on the face have been reinstalled yet.

[Jon]

Golden rule is, until the movement has been totally disassembled, cleaned, assembled and lubricated and adjusted, there is little use in a timegrapher or trying to regulate the movement, because it isn't telling you anything about the health or running of the movement, as it hasn't been lubricated.

So, what you are seeing on your timegrapher is just that, a movement with no lubrication, so you are not going to gain any useful information from your timegrapher. In fact, if you are going to put it on a timegrapher, it will be giving you very misleading info, because it hasn't been serviced.

Also when you say you adjusted the pallet fork, how did you do that? And what was the reason to straighten the banking pin, apart from it being bent? Did you check the guard pin and horn shake before doing that? The banking pin may have deliberately been set like that for a reason, I don't know. It shouldn't be really bent, but it didn't happen by accident, so straightening it might not have been a good idea without doing the proper checks of the escapement to see it is adjusted correctly. I do suspect by straightening the banking, the total lock of the pallet stone with the escape wheel tooth has been changed and the distance the guard pin is from the safety roller has changed on one side (guard pin shake), as well as the distance the impulse jewel is from the horn has also changed on one side.

This topic may help understand more about the Swiss lever escapement and the checks

 

[nevenbekriev]

Hi Nigel,

The first thing that is seen here is the huge difference in amplitude in both horizontal positions. And it is has probably nothing to do with the pallets lubrication. So, apart from all the rest, I will advice to check the balance and especially the hairspring. 2809 is big movement and there is a lot of space for the hairspring, but it is a Breguet one ans is made of pretty soft material. Do the free oscillations test and see if there is difference in both horizontal positions.

And yes, this is You first watch attempt and You start with pallets and banking pins position adjustment. Do You really know how to do this?

[NigelTufnel]

Hi @nevenbekriev

 

Thanks so much for your reply.  Jon's comments got me thinking, and while I thought I had cleaned and lubed all of the right places I seemed to have missed one of the balance wheel pivots.  Dry and dirty.  I've cleaned and lubricated it, and lubricated the pallet stones.

As for the pallet stone adjustments, sadly I was left with little choice but to attempt it.  The stones were loose in the fork due to the shellac turning to dust. My donor movement also had disintegrated shellac.  I went by the information in Henry B. Freid's book "The Watch Repairers Manual."  The problem I was left with was that the exit stone could not be adjusted correctly.  It was at least 1 jewel's width into the lock, if not more, practically hitting the innermost part of the tooth.  My only choice was to straighten the banking pin.  Then the stone was in the right range and a little heat and a microscope with a calibrated reticule and I got it to match the book.

Of course you may all look in dismay at me for attempting this, but the watch is running far better than it ever has since I bought it. Please let me share my current dial up/dial down images for you to examine.  Hopefully you can give me even further insight.  Images were taken about 10-12 hours after a full wind. 

The clean one is dial down.

 

 

Edited September 10, 2024 by NigelTufnel

[nevenbekriev]

OK, let us adopt that the escapement here is not the problem, as You have good amplitude in one horizontal position. But, as I said before, the other horizontal position is with bad amplitude and this most probably is not due pallets  or banking pins adjustment. Please, do the free oscillations test with only the balance in the movement and share the results. By the way, are the timegrapher readings of the amplitude correct?

[NigelTufnel]

5 hours ago, nevenbekriev said:

. Please, do the free oscillations test with only the balance in the movement and share the results

Not sure what this is honestly!

[nevenbekriev]

Free oscillations test – remove the pallet fork and with the balance in place, turn the balance to 180 degr. and release it, then count the number of free oscillations to the full stop. Here one oscillation is swing to the left +swing to the right, so You must count only swinging to one direction, or just the expandings  of the hairspring. The good result will be about 150 (in both horizontal positions) for this movement – then we will know the balance, bearings/pivots, hairspring – all OK.

[NigelTufnel]

@nevenbekriev Oh, thank you so much for that description. I tried searching online and was unable to find it.

I am grateful to you and @Jon for trying to help me.  I have to apologize for being a noob but also because this project started about 9-10 months ago.  In my defense, when I opened this watch I just bought a time grapher and thought this was a simple regulator problem.  The issues kind of snowballed from there like a home improvement job.  Family tragedy in December/January made me put this down and honestly I did not recall as well as I thought what was and was not done.  Since my first posts in the thread I doubted my cleaning and oiling of the balance pivot jewels. I first thought I only missed the dial side but after cleaning and lubing both and more Rodico on the balance staff the watch is doing exceptionally well.  I had not paid attention to this note at 17Jewels or perhaps I would not have gotten here:

Quote

It got a simple service, but the balance wheel bearings could not be cleaned, because of non-available spare parts and the too large risk to damage the otherweise well working movement.

So I went where angels feared I guess and now have very comparable results dial up/dial down.  After about 12 hours from a full wind:

DU:  +31s/d , 225 Deg, BE 2.3ms

DD: +35s/d, 219 Deg, BE 2.6ms

TG lines are very clean.

I note the watch sample at 17Jewels had more than 250 degrees of amplitude DU/DD. 

So if I may impose upon you again, without causing too much frustration, and recognizing this is a 70+ year old movement, what would you recommend now? Should I do the balance oscillation test?  I've seen recommendations to always replace the mainspring, as well as polish the barrel and arbor.  I did clean and lubricate the barrel and arbor (yes, of this I'm 100% sure!) but did not do any polishing and the mainspring is AFAIK original. 

Edited September 11, 2024 by NigelTufnel

[RichardHarris123]

Do the free oscillation test, replacing the mainspring depends on the condition of the existing spring. If it's set, then yes replace it.  

[SwissSeiko]

On 9/9/2024 at 9:33 PM, NigelTufnel said:

Hi @nevenbekriev

As for the pallet stone adjustments, sadly I was left with little choice but to attempt it.  The stones were loose in the fork due to the shellac turning to dust. My donor movement also had disintegrated shellac.  I went by the information in Henry B. Freid's book "The Watch Repairers Manual."  The problem I was left with was that the exit stone could not be adjusted correctly.  It was at least 1 jewel's width into the lock, if not more, practically hitting the innermost part of the tooth.  My only choice was to straighten the banking pin.  Then the stone was in the right range and a little heat and a microscope with a calibrated reticule and I got it to match the book.

Honestly, you're well on your way to being a great watchmaker if you undertook this type of repair. This is something I see even seasoned watchmakers don't want to mess with. If you' re interested more in escapement theory, which I think everyone should be, have a look at this book. Anyone can clean and lube a watch. It takes real skill to start messing with the geometry of the escapement.

escapement book.pdf

[NigelTufnel]

Thanks for the advice, everyone.  I promise to do the oscillation test, but I also think I'm going to get a new mainspring.  I'd like to go back and polish the barrel. Also, I'm a little over stressed at too many tiny screws and need a little break before I go back to removing the fork bridge again.   Bear with me if I go silent for a while, as my day job and stress levels affect my ability to make headway here.

 

Thanks again!

 

@SwissSeiko Thanks so much for the kind words.  It seemed a lot less risky when I started!

[lucgyver]

can you show a couple of pics of the movement?

[NigelTufnel]

17 minutes ago, lucgyver said:

can you show a couple of pics of the movement?

It really doesn't look very different than you find online like at https://17jewels.info/movements/w/wostok/wostok-2809/

but maybe more scratched. My pics don't come out very well I'm afraid.

[nevenbekriev]

Hi Nigel,

Well, don't expect miracles from barrel arbor polishing. I mean it is good to try as to know how it works for gaining experience, but this are mainly things that can fill hours of videos in video channels. As for the mainspring, it depends on the condition of the original spring. I don't have much experience with this calibre as it is pretty rare in my country. I have worked on some of them in the distant past, but even don't remember if the spring is of 'modern' white alloy or steel with tempered color. But, my personal experience with USSR watches is that they have good springs and replacing them is useless unless they are broken or damaged in some other way. This calibre has special 3th wheel that needs some care, as it may be trap for loosing amplitude. Take care to ensure the free rotating table of it rotates really free, and put small quantity of oil in it's bearing on the pinion. Free oscillations test will show the balance condition. Make sure there are no losses of energy there, then good amplitude is guaranteed.

The pallets adjustment is something that one should not be frightened of. The adjustment itself is simple thing, but one has to know how to check if the adjustment is correct as to ensure the escapement doesn't loose energy and all safety functions work as they should, only then  the things will come in their place. This comes with some practice and experience gaining. Try to wear the watch for awhile in normal conditions to ensure there are no stops from the escapement, this is one of the ways to check the safety functions.