What could be the cause of this widely varying rate?

[VWatchie]

I have a newly serviced automatic Vostok cal. 2416 with a decent amplitude in all positions, very small beat errors, and a mainspring with a full power reserve after a normal day of use.

Despite having a healthy amplitude, beat error, and power reserve, the rate widely varies. Here are the rates I got while letting the watch rest on its back overnight in a room with the same temperature (give or take one or two degrees) night after night. Each rate represents a night’s rest of about 9 hours. +8, +7, +4, +4, +3, +4, +12, +7, +8, +14, +23, +7, +9, +16, +18, +17, +22, +21, +30, +15.

I know the rate may fluctuate by a few seconds, but in this example, the rates vary between +4 and +30 seconds.

Any ideas?

[nevenbekriev]

Was the watch fully wound every night when left to resr back down? Or, You just take it off the wrist? If not, then the torque in the spring can differ a lot every morning.

[VWatchie]

9 minutes ago, nevenbekriev said:

Was the watch fully wound every night when left to resr back down?

That's a good question and one that I don't have the answer to. The only time I tested the power reserve was after a day of normal use and I got 33 hours out of it. The power reserve is specified to 31 hours so I have just been assuming fully would. I try winding it up fully for a few nights and will see what happens.

[JohnR725]

8 hours ago, VWatchie said:

Vostok cal. 2416

Just because I like to see what were talking about I assume you mean something like this?

https://17jewels.info/movements/w/wostok/wostok-2416b/

7 hours ago, nevenbekriev said:

Was the watch fully wound every night when left to resr back down? Or, You just take it off the wrist? If not, then the torque in the spring can differ a lot every morning.

Not having a consistent power can definitely have an effect on timekeeping.

8 hours ago, VWatchie said:

Vostok cal. 2416 with a decent amplitude in all positions, very small beat errors,

One of the things I'd be curious to know if it's fully wound up looking at the watch in the various positions what does timekeeping look like. Then 24 hours later what does timekeeping specifically rate.  What I'm curious about is the effect of amplitude on rate over time.

7 hours ago, VWatchie said:

I have just been assuming fully would.

One of the problems with an automatic watch is it depends upon how active you are a variety of things as to whether it's fully wound up or not.

One of the things I would look at is spacing of your regulator pins it's amazing especially when were looking at critical amounts of time keeping the effect of time keeping an amplitude and regulator pins especially if there open just a hair too far.

 

[VWatchie]

Now that you mention it, it could very well be a matter of power. As I mentioned, I have just been assuming a full power reserve after a full day of wearing it, but I could definitely be wrong about that. When I went to bed nine hours ago I wound it manually and the (average) rate during the night was -1 second. Usually, it's several seconds plus (as seen in my previous post). I've just wound it up again and will check in nine hours. If the rate is the same, then that will pretty much for sure indicate it's related to the power on the mainspring.

1 hour ago, JohnR725 said:

Just because I like to see what were talking about I assume you mean something like this?

Absolutely, I just forgot about the "b"-thing, and if you want to see what it looks like in detail, there are several pictures here. Not a 2416B but a slightly modified version of it named 2431 (24-hour version).

1 hour ago, JohnR725 said:

One of the things I'd be curious to know if it's fully wound up looking at the watch in the various positions what does timekeeping look like. Then 24 hours later what does timekeeping specifically rate.  What I'm curious about is the effect of amplitude on rate over time.

I'll see if I can't provide the information a bit later.

Edited November 17, 2023 by VWatchie

[VWatchie]

On 11/17/2023 at 6:15 AM, JohnR725 said:

One of the things I would look at is spacing of your regulator pins it's amazing especially when were looking at critical amounts of time keeping the effect of time keeping an amplitude and regulator pins especially if there open just a hair too far.

I almost missed this sentence and as I know very little about it I'd like to know more. I know it's critical to keep the balance spring bouncing between the index pins but nothing much beyond that. Can you talk a bit more about it or refer me to a good source?

About my watch having erratic rates, experiments are underway...

[RichardHarris123]

14 minutes ago, VWatchie said:

know it's critical to keep the balance spring bouncing between the index pins but nothing much beyond that. Can you talk a bit more about it or refer me to a good source?

About my watch having erratic rates, experiments are underway...

Try this 

https://oakandoscar.com/blogs/the-dial/from-the-bench-regulation-part-1#:~:text=That little gold fork (called,making the watch run faster.

[Neverenoughwatches]

55 minutes ago, VWatchie said:

I almost missed this sentence and as I know very little about it I'd like to know more. I know it's critical to keep the balance spring bouncing between the index pins but nothing much beyond that. Can you talk a bit more about it or refer me to a good source?

About my watch having erratic rates, experiments are underway...

If the hairspring is spending more time between the pin spacing rather than touching the pins then the active point is moved back to where the hairspring is pinned at the stud. So i guess as the amplitude decreases the spring will oscillate weaker touching the pins to a lesser degree thereby slowing the rate, more noticeable if the pin spacing is too wide ( i know not an in line theory with the increased rate you are noticing ). But what you might be experiencing is poor isochronism as the amplitude is reduced. 

[JohnR725]

6 hours ago, VWatchie said:

Can you talk a bit more about it or refer me to a good source?

Here's a very good reference and a review of the reference. But minor problem with reference material like this and he even brings this up but he doesn't pointed out as a problem. Reference books like this cover a lot of stuff from manufacturing point of view. So he talks about using it to make hairsprings. You have an existing watch is not going to redesign the watch so it's going to have design flaws. Even if the watch does keep really good time.

https://youtu.be/op68gwVvsCo?si=7-jq6k3mRsgTqUeZ

5 hours ago, Neverenoughwatches said:

But what you might be experiencing is poor isochronism as the amplitude is reduced. 

Interesting wording let's look at what Wikipedia says

https://en.wikipedia.org/wiki/Isochronous_timing

Let's see what Wikipedia has to say watch is isochronous if it runs at the same rate regardless of changes in its drive force Notice the reference to drive force the watch should keep the same time regardless of amplitude unfortunately amplitude does affect timekeeping.

Another Wikipedia entry let's look at mainsprings

https://en.wikipedia.org/wiki/Mainspring

Notice the pictures the mainspring is like the top right out of the package and then the lower left the Elgin Springs. Reference to the interesting curvatures designed to produce more even force as the mainspring unwinds.

Unfortunately if you take mainsprings out of the ring you find that they don't always have this really nice curvature like they're supposed to. I find a lot of times with modern pocket watch Springs the most amusing was one that basically had the center curve and went straight out and had basically no curve at all that is going to produce very uneven power. Other Springs look almost set but the brand-new and some of the later generation both Hamilton Elgin tend to be some of the nicest looking mainsprings because they do have the proper curves versus the modern Springs which often don't

so if you don't have a mainspring of the right shape you're going to have an even power so if there is manufacturing inconsistencies that can be an issue especially when we want to be super nitpicky on timekeeping down to the second.

On 11/16/2023 at 9:15 PM, JohnR725 said:

One of the things I'd be curious to know if it's fully wound up looking at the watch in the various positions what does timekeeping look like. Then 24 hours later what does timekeeping specifically rate.  What I'm curious about is the effect of amplitude on rate over time.

Did you notice this question why do you think I ask this? If you looked at your watch dial down which most people is the only position they looked at the regulate the watch and then move it to crown down what happens for timekeeping?

Often times people love to have amplitude and if you around the end your pivots you'll get lots of amplitude but ill have a problem as soon as you go to the crown positions is more friction you lose your amplitude. It's why typically the ends the pivots are flattened to make their amplitude more even with the pendant positions.

Basically looking at the watch in more than one position can show the effect of amplitude changes from dial positions the pendant positions and then 24 hours later with the timekeeping look like

you also find related the mainspring is our watches that will run 48 hours and 56 hours another attempt to get a more even powered mainspring. So usually not necessarily at the extremes at least at the extremes of running out of energy like you would be of it had a watch that only ran for 30 hours for instance

then those pesky hairspring regulator pins it would be nice if we just break them off and not deal with them at all as timekeeping would be so much nicer.

Regulator pins spacing depends upon type of hairspring you have.

Here's an interesting image obviously a flat hairspring. So we can see the effect of the hairspring bouncing off the regulator pins as long as it's doing that it should keep relatively linear time. But as the amplitude drops basically the regulation point moves and the watch slows down. Opening the pins up will make this worse and closing has issues because flat hairsprings are supposed to have some spacing. Basically if you took the thickness of the hairspring multiplied it by two that's the spacing between the pins. But like everything else that can be some minor variations here

Then what happens if you're not centered between the pins. This will also depend upon how strongly are pushing the hairspring out of between the pins. For instance I once worked at a shop where we were instructed to bend a hairspring so it always touched one of the pins. Which would work fine as long as they hairspring never got enough amplitude the liftoff.

 

 

[Neverenoughwatches]

2 hours ago, JohnR725 said:

Here's a very good reference and a review of the reference. But minor problem with reference material like this and he even brings this up but he doesn't pointed out as a problem. Reference books like this cover a lot of stuff from manufacturing point of view. So he talks about using it to make hairsprings. You have an existing watch is not going to redesign the watch so it's going to have design flaws. Even if the watch does keep really good time.

https://youtu.be/op68gwVvsCo?si=7-jq6k3mRsgTqUeZ

Interesting wording let's look at what Wikipedia says

https://en.wikipedia.org/wiki/Isochronous_timing

Let's see what Wikipedia has to say watch is isochronous if it runs at the same rate regardless of changes in its drive force Notice the reference to drive force the watch should keep the same time regardless of amplitude unfortunately amplitude does affect timekeeping.

Another Wikipedia entry let's look at mainsprings

https://en.wikipedia.org/wiki/Mainspring

Notice the pictures the mainspring is like the top right out of the package and then the lower left the Elgin Springs. Reference to the interesting curvatures designed to produce more even force as the mainspring unwinds.

Unfortunately if you take mainsprings out of the ring you find that they don't always have this really nice curvature like they're supposed to. I find a lot of times with modern pocket watch Springs the most amusing was one that basically had the center curve and went straight out and had basically no curve at all that is going to produce very uneven power. Other Springs look almost set but the brand-new and some of the later generation both Hamilton Elgin tend to be some of the nicest looking mainsprings because they do have the proper curves versus the modern Springs which often don't

so if you don't have a mainspring of the right shape you're going to have an even power so if there is manufacturing inconsistencies that can be an issue especially when we want to be super nitpicky on timekeeping down to the second.

Did you notice this question why do you think I ask this? If you looked at your watch dial down which most people is the only position they looked at the regulate the watch and then move it to crown down what happens for timekeeping?

Often times people love to have amplitude and if you around the end your pivots you'll get lots of amplitude but ill have a problem as soon as you go to the crown positions is more friction you lose your amplitude. It's why typically the ends the pivots are flattened to make their amplitude more even with the pendant positions.

Basically looking at the watch in more than one position can show the effect of amplitude changes from dial positions the pendant positions and then 24 hours later with the timekeeping look like

you also find related the mainspring is our watches that will run 48 hours and 56 hours another attempt to get a more even powered mainspring. So usually not necessarily at the extremes at least at the extremes of running out of energy like you would be of it had a watch that only ran for 30 hours for instance

then those pesky hairspring regulator pins it would be nice if we just break them off and not deal with them at all as timekeeping would be so much nicer.

Regulator pins spacing depends upon type of hairspring you have.

Here's an interesting image obviously a flat hairspring. So we can see the effect of the hairspring bouncing off the regulator pins as long as it's doing that it should keep relatively linear time. But as the amplitude drops basically the regulation point moves and the watch slows down. Opening the pins up will make this worse and closing has issues because flat hairsprings are supposed to have some spacing. Basically if you took the thickness of the hairspring multiplied it by two that's the spacing between the pins. But like everything else that can be some minor variations here

Then what happens if you're not centered between the pins. This will also depend upon how strongly are pushing the hairspring out of between the pins. For instance I once worked at a shop where we were instructed to bend a hairspring so it always touched one of the pins. Which would work fine as long as they hairspring never got enough amplitude the liftoff.

 

 

So in low amplitude conditions and vertical positions where the regulating pins are either above or below the hairspring the rate would be close to accurate as the spring oscillations might not be strong enough to push off either of the pins that it rests on through gravity.

2 hours ago, JohnR725 said:

Interesting wording let's look at what Wikipedia says

https://en.wikipedia.org/wiki/Isochronous_timing

Let's see what Wikipedia has to say watch is isochronous if it runs at the same rate regardless of changes in its drive force Notice the reference to drive force the watch should keep the same time regardless of amplitude unfortunately amplitude does affect timekeeping

Is the isochronism also part of the hairspring's ability to keep the same tempo of the impulse pin passing through the fork slot during different amplitude ranges. Ie. If the amplitude is 150° the balance should be moving at half the speed it would be if the amplitude were 300°. 

Edited November 18, 2023 by Neverenoughwatches

[VWatchie]

10 hours ago, Neverenoughwatches said:

Is the isochronism also part of the hairspring's ability to keep the same tempo of the impulse pin passing through the fork slot during different amplitude ranges.

That's a very interesting question. I don't know the answer but I would guess not. As I understand it, isochronism only means that the frequency is independent of the amplitude.

The amount of energy from the impulse pin hitting the fork slot must be less when the amplitude is low and that, I assume, affects the timekeeping but is mostly negligible I would guess.

So the results (average rate) of testing the watch. Each number represents a test of a full wound, the same temperature, resting on its back for about 9 hours.

Vostok 2416b: -0.8, -5.3, -0.4, -2.4, -3,5

In my eyes, that looks pretty normal and in line with what I would expect from a healthy 2416b. Given these ideal conditions I would expect the rate to only differ by a few tenths of a second but not even my best running timepiece, an ETA 2804-2, can accomplish that.

[Neverenoughwatches]

1 hour ago, VWatchie said:

That's a very interesting question. I don't know the answer but I would guess not. As I understand it, isochronism only means that the frequency is independent of the amplitude.

 John will have some more thoughts on this. I know the mainspring cannot be fully consistent with delivering the same energy as it unwinds ( maintaining isochronoism in the movement ) I just wondered if a hairspring was not perfectly manufactured that also its time and distance travelled ( speed ) would not remain proportional with amplitude ?

1 hour ago, VWatchie said:

The amount of energy from the impulse pin hitting the fork slot must be less when the amplitude is low and that, I assume, affects the timekeeping but is mostly negligible I would guess.

that has to be where the ability to be isochronous comes in. The energy the mainspring is delivering is ever decreasing, but the hairspring still has to keep the exact same tempo up for the watch to remain accurate.  So the speed of the balance has to be perfectly in proportion to the amplitude it receives. The tic and toc timing must always be exactly the same regardless of the speed that the balance is traveling. So does that rely on the hairspring entirely or maybe all of the balance components . Does the friction qualities in the balance also change at different speed ranges ? Is friction less or more at higher speeds ? Another question to consider, am i getting far too carried away with looking at this ?

Edited November 19, 2023 by Neverenoughwatches

[Nucejoe]

Just curious, what grade hairspring is in Vostok ? 

[Neverenoughwatches]

1 hour ago, Nucejoe said:

Just curious, what grade hairspring is in Vostok ? 

Is this in line with my thoughts Joe ?, a better quality grade of hairspring will be more reliable and helps with consistent accurate time keeping ? 

[Nucejoe]

33 minutes ago, Neverenoughwatches said:

Is this in line with my thoughts Joe ?, a better quality grade of hairspring will be more reliable and helps with consistent accurate time keeping ? 

 Isn't the rate of a watch in static state  independent of hairspring's grade?    I believe the grade comes into effect only in dynamic state .

( on wrist or in pocket ). 

Rgds

 

 

 

[Neverenoughwatches]

1 hour ago, Nucejoe said:

 Isn't the rate of a watch in static state  independent of hairspring's grade?    I believe the grade comes into effect only in dynamic state .

( on wrist or in pocket ). 

Rgds

 

 

 

I dont really understand what you mean here Joe. How exactly is a watch in a static or dynamic state other than non running ?

[JohnR725]

8 hours ago, VWatchie said:

isochronism only means that the frequency is independent of the amplitude.

Yes that is exactly what it means. The simplistic is does your watch keep time with varying amplitudes.

8 hours ago, VWatchie said:

ETA 2804-2

 

As you picked the caliber let's look at the timing specifications for this watch. Technical specifications are interesting for the various watch companies not always seen by the watchmaker because they could be separate documents. So for instance the manufacturing information I've attached a PDF for this watch. Then this watch comes in two separate grades with the only difference in the image below timing specifications nothing else. Some of the other grades will have more differences than just timing like better balance wheel with better hairspring and even better mainspring or different mainspring with different alloy. But here we only get timing it some

Timing specifications are interesting in that basically it's a window and the factory or for that matter people at I know that work at service center is they just have to get the watch with in the window they do not regulate to zero. To the supplier given out of range your watch will be anywhere within this range and be acceptable.

Then all we care about is isochronism in this particular case CH sans for dial up the watches checked over 24 hours and we have a number. They do not look at the watch in various positions as that adds complications to the sort of thing.

 

19 hours ago, Neverenoughwatches said:

Is the isochronism also part of the hairspring's ability to keep the same tempo of the impulse pin passing through the fork slot during different amplitude ranges. Ie. If the amplitude is 150° the balance should be moving at half the speed it would be if the amplitude were 300°. 

You do realize I don't have a PhD in all this?

8 hours ago, VWatchie said:

The amount of energy from the impulse pin hitting the fork slot must be less when the amplitude is low and that, I assume, affects the timekeeping but is mostly negligible I would guess.

The unfortunate reality is the escapement screws up timekeeping. For instance if you watch was running at 150° the lift angle typically is around 50° one third of that would be under the influence of the escapement.

Let's look at it interesting a video. Normally I like to refer people to this video for the lever escapement only and I never watch the rest of the video. But today the rest the video is more interesting. Or basically the entire video.

In an absolute perfect oscillation system you would like to have zero influenced from everything. So anything that influences your balance wheel will screw up timekeeping.

The unfortunate reality is the escapement is a necessary evil. The escapement supplies energy but it also screws up the timekeeping. Remember the lift angle number that's the number of degrees that the escapement is screwing things up.

So we can change our watches unfortunately were stuck with a lever escapement but what if we were manufacturing what if we were clever like for instance the video different escapement it should screw up the timekeeping less and bump the price up out of our site so we will never get the service one of these.

https://youtu.be/gIOd7Bpuw9U?si=oK4NVzdqQBsp92-9

Let's look at a different example of this let's go back to Wikipedia lookup escapement and you'll notice the word isochronism lurking here and there

https://en.wikipedia.org/wiki/Escapement

So he can read through all of it but all I care about is one particular escapement the detent escapement and is going to quote from Wikipedia. Notice what it says most accurate escapement for balance wheel timepieces.

In order to keep perfect time the balance wheel shouldn't be influenced by anything including the escapement. If you can reduce the influence of the escapement you should improve timekeeping. So for instance the detent escapement only impulses in one direction the balance wheel will pass by in the other direction with almost or basically no effect at all. It's really quite a fascinating escapement the watch

Notice the second paragraph disadvantages it's fragile. One of my friends used to service Marine chronometers and when things go bad on these they can go very very bad in a repair will become extremely extensive. If you look carefully at the design there's only one jewel holding the escape wheel in place and if it's moved by curious people playing with the balance wheel or a variety of reasons that jewel might decide to fail the destruction will be very expensive.

The detent is a detached escapement; it allows the balance wheel to swing undisturbed during most of its cycle, except the brief impulse period, which is only given once per cycle (every other swing).[38] Because the driving escape wheel tooth moves almost parallel to the pallet, the escapement has little friction and does not need oiling. For these reasons among others, the detent was considered the most accurate escapement for balance wheel timepieces.[41] John Arnold was the first to use the detent escapement with an overcoil balance spring (patented 1782), and with this improvement his watches were the first truly accurate pocket timekeepers, keeping time to within 1 or 2 seconds per day. These were produced from 1783 onwards.

However, the escapement had disadvantages which limited its use in watches: it was fragile and required skilled maintenance; it was not self-starting, so if the watch was jarred in use so the balance wheel stopped, it would not start up again; and it was harder to manufacture in volume. Therefore, the self-starting lever escapement became dominant in watches.

 

 

 

ETA 2804-2 - Manufacturing Information.PDF

[Neverenoughwatches]

3 hours ago, JohnR725 said:

You do realize I don't have a PhD in all this?

Haha sorry John, i was getting a bit carried away asking questions, it happens when i have too much time to think.

3 hours ago, JohnR725 said:

13 hours ago, VWatchie said:

isochronism only means that the frequency is independent of the amplitude.

Yes that is exactly what it means. The simplistic is does your watch keep time with varying amplitudes

It does but it doesn't just apply to the qualities of a mainspring, any oscillator can be isochronal. The hairspring would effect the watch's isochronism, its about its ability to keep the same time. It can be regulated within its capacity to be regulated, a better grade of hairspring would have a better capacity to keep accurate time keeping. Not sure why i went down this path, just an explanation of why watchie had different rates on different days. A better grade of hairspring would probably have a tighter rate over the course of the same days wouldnt it.

Edited November 19, 2023 by Neverenoughwatches

[Nucejoe]

4 hours ago, Neverenoughwatches said:

I dont really understand what you mean here Joe. How exactly is a watch in a static or dynamic state other than non running ?

You must  have browsed through my post in a hurry to get to the next post quick. 

Notice I say " the watch "  in dynamic state , not  "the oscilator" ,  as you move your wrist you subject the oscilator to angular  acceleration/ declerate, furthure the watch goes through infinate positions on wrist. On tg , however,  the watch is sitting still, and is not subjected to external forces, other than gravity which is constant and not dynamic.

So , dynamic  external forces don't come into the picture with the watch in static position, namely on bench or tg. 

You keep forgetting that I  am non native English speaker matey.

Rgds 

 

[Neverenoughwatches]

2 hours ago, JohnR725 said:

⁹

9 minutes ago, Nucejoe said:

You must  have browsed through my post in a hurry to get to the next post quick. 

Notice I say " the watch "  in dynamic state , not  "the oscilator" ,  as you move your wrist you subject the oscilator to angular  acceleration/ declerate, furthure the watch goes through infinate positions on wrist. On tg , however,  the watch is sitting still, and is not subjected to external forces, other than gravity which is constant and not dynamic.

So , dynamic  external forces don't come into the picture with the watch in static position, namely on bench or tg. 

You keep forgetting that I  am non native English speaker matey.

Rgds 

 

Ah gotcha Joe, i was discussing static and dynamic poising eleswhere earlier today, your statement threw me . Thanks For explaining. 

 

7 hours ago, Nucejoe said:

 Isn't the rate of a watch in static state  independent of hairspring's grade?    I believe the grade comes into effect only in dynamic state .

( on wrist or in pocket ). 

Rgds

 

 

 

I would think more so yes when the watch is moving around. Now I'm trying to think what influences can happen inside a watch while it is stationary that can effect the rate over a period of days. Frictional changes ? temperature, magnetism,  humidity, gravity, lunar tidal cycles, magnetic pole shift.

14 hours ago, VWatchie said:

On 11/18/2023 at 10:44 PM, Neverenoughwatches said:

Is the isochronism also part of the hairspring's ability to keep the same tempo of the impulse pin passing through the fork slot during different amplitude ranges.

That's a very interesting question. I don't know the answer but I would guess not. As I understand it, isochronism only means that the frequency is independent of the amplitude.

if a hairspring is perfectly isochronous then given constant momentum it would oscillate at a constant rate regardless of how far it expands and contracts, ( the degree of expanding and contracting is seen as its amplitude, its amplitude varies depending on the amount of energy it receives from the propelled balance ). As john has mentioned other influences effect the hairspring's oscillation rate and amplitude, interaction of the escapement for one slows it down, there must be variations in these other influences  that creates inconsistent timekeeping even when the watch isn't moved.

[JohnR725]

7 hours ago, Neverenoughwatches said:

there must be variations in these other influences  that creates inconsistent timekeeping even when the watch isn't moved.

I we still talking about the effect of amplitude and what causes it to be non-consistent or are you looking for something different?

[Neverenoughwatches]

1 hour ago, JohnR725 said:

I we still talking about the effect of amplitude and what causes it to be non-consistent or are you looking for something different?

No not amplitude, we know why amplitude is non consistent, that is variable according to the amount of energy the hairspring receives. Just the hairspring's oscillation rate on consecutive days under the same conditions. 

23 hours ago, VWatchie said:

 

So the results (average rate) of testing the watch. Each number represents a test of a full wound, the same temperature, resting on its back for about 9 hours.

Vostok 2416b: -0.8, -5.3, -0.4, -2.4, -3,5

In my eyes, that looks pretty normal and in line with what I would expect from a healthy 2416b. Given these ideal conditions I would expect the rate to only differ by a few tenths of a second but not even my best running timepiece, an ETA 2804-2, can accomplish that.

How long was the watch on the timegrapher for ? Enough time for the watch to settle and the rate to be consistent ? Was the watch worn inbetween the 9 hour rest period ?

Edited November 20, 2023 by Neverenoughwatches

[B52]

On 11/16/2023 at 9:29 PM, VWatchie said:

I have a newly serviced automatic Vostok cal. 2416 with a decent amplitude in all positions, very small beat errors, and a mainspring with a full power reserve after a normal day of use.

Despite having a healthy amplitude, beat error, and power reserve, the rate widely varies. Here are the rates I got while letting the watch rest on its back overnight in a room with the same temperature (give or take one or two degrees) night after night. Each rate represents a night’s rest of about 9 hours. +8, +7, +4, +4, +3, +4, +12, +7, +8, +14, +23, +7, +9, +16, +18, +17, +22, +21, +30, +15.

I know the rate may fluctuate by a few seconds, but in this example, the rates vary between +4 and +30 seconds.

Any ideas?

yes one idea...movement is low class quality. I repaired one piece recently and was piece of rubbish. Nice looking watches but quality of the movement was very poor. Ivan started manufacturing a movement as usually but for very first time the result was not Kalashnikov.

[Nucejoe]

1 hour ago, B52 said:

yes one idea...movement is low class quality. I repaired one piece recently and was piece of rubbish. Nice looking watches but quality of the movement was very poor. Ivan started manufacturing a movement as usually but for very first time the result was not Kalashnikov.

Something ought to change to cause a change in rate.

What changed in this low quality movement, in nine hrs  ? 

Rgds

 

[Neverenoughwatches]

1 hour ago, Nucejoe said:

Something ought to change to cause a change in rate.

What changed in this low quality movement, in nine hrs  ? 

Rgds

 

Tbf the range difference was only 4.9 seconds over 5 days, which sounds pretty good, although watchie was expecting less than one second difference. He didn't say if the watch had been worn inbetween the seperate nine hours of no movement. Would a few degrees of temperature change between each day cause the rate to change. Watchie did say the rest was about nine hours so it sounds like the rest wasn't precisely timed also the full wind before the watch was set to rest may not have been identical each day. After each nine hours of rest was the amplitude exactly the same ?, we only have the rate to study. So we are now back to how isochronous is the hairspring and what varying effects and changes of the escapement or anything else happen on any of the given 5 days. Its probably not something we can pinpoint and answer, not unless anyone here designs watch movements.