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Timegrapher-chart experts advice please....


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I acquired a N.O.S. Poljot / MakTime 3133 movement. According to the seller, the movement ran fine. On the eBay pictures the movement looked great and in good shape. I received the same movement (serial number etc).

Somehow, somewhere the movement got damaged between the sellers eBay pictures and upon reception. The blocking-lever was found stuck between the chronograph seconds-wheel and the chronograph bridge. That was a problem which had to be dealt with straight away. Since the movement allegedly ran well, I didn't put it on the timegrapher before the service. Stripped the movement and assesses the damage. Only a slight bend blocking lever seemed all.

Serviced the movement and build it back together. There were no hick-ups and the  service went smooth. The movement started ticking at first spring tension ......all looked well.

I had it run for 24hrs and put it this morning on the timegrapher to see what fine tuning had to be done ........ however, this was what I got to see (I guesstimate that the main-spring is still 1/2 wound)

3133UK-4.PNG.2a71e8cf84e187db277901bb0a6e3048.PNG

I do suspect a escape-wheel and/or pallet-fork problem, but I like to consult the experts on this forum first to hear what they think where the problem lays and what can be done ?

Hope to hear ...... ;)

Roland.

Edited by Endeavor
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I'm not an expert on this topic, but I am quite interested in seeing what the crowd has to say. To my eye, it appears like the watch is running ok, albeit a bit slow, for about half the way round the escape wheel - 7 or 8 teeth, on both the entry and exit pallets. But, the second half is a mess. Is it possible that:

o The wheel is out of true?
o There is dirt, smeared oil or other on some of the teeth?

Examine the escape wheel carefully - remove it and check for true or other defects. Clean it and reinstall.

I suppose it's also possible that the noise is coming from somewhere other than the escapement. Are you running the chronograph module during the test? Perhaps shut it down. 

Don't put too much stock in my response - I'm just thinking out loud. 

Good luck!

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@sstakoff Thank you for your reply ;)

The chronograph was not engaged, in fact I took the whole chrono off after I posted this thread, but that didn't make any change, which was to expect.

Counting the dots, it seems to "work" for about 22 dots before it goes haywire for a little while. The escape wheel has just been cleaned and I can't see anything obvious, the pallet jewels look fine to with a 5x loupe.

I will take it all apart again and check your suggestions. But before doing so, it would be nice to get some more responses so I'm armed with more suggestions /knowledge where to look for ......

Edited by Endeavor
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Check the other train wheels for similar errors - being out of true. That movement is not an automatic, correct? If it were, I would also make sure that the mainspring is cleaned and the proper braking grease (8217?) is applied to the barrel wall to prevent irregular slipping, etc.

Edited by sstakoff
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The amplitude is very low which suggests that the balance wheel is not turning freely. My guess would be that the hairspring is touching on something as that would explain the periodic high rate.

Take a good look at the balance action with a 15x loupe and see if you get the same behaviour in different orientations (the watch that is, not you :wacko:)

Edited by StuartBaker104
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Hello All;

Thank you very much for your suggestions :)

I stripped and cleaned the balance assembly, pallet fork and escape wheel. The highest magnification I have is a Sternkreuz 10x loupe. I couldn't find anything wrong with the pivots, the escape teeth, pallet-jewels nor the balance hair-spring, roller-jewel or pivots. Installed all the three components (this time no oil on the pallet jewels)  and the result was better, but still signs of the above pattern.

Changed out the balance wheel and hair-spring for a brand new set and the results hugely improved. This morning I stripped it all again, cleaned and oiled where required and the results are as below;

Dial Down;

3133UK-NB-DD.PNG.1d89ef06cd8c89b65ce67c984ccdb3ff.PNG

Dial up;

3133UK-NB-DU.PNG.d021b04d7fc262c345b607ca01c316f4.PNG

Crown Down;3133UK-NB-CD.PNG.94797b2840e90474a74e01683ee243cb.PNG

Crown Up;

3133UK-NB-CU.PNG.dd9ce22fa44aa878338ab9d1d75ac497.PNG

It shows some "wave" pattern in CU / CD which could come from the drive. Some "off-Line" dots could be W.O.S. interference or originate from the watch? The Amplitude isn't the highest, but the watch hasn't run a lot since the complete service. The beat-error seems pretty consistent in all four positions.

Had another close look at the "old" balance with my 10x, but can not see anything wrong with the staff-pivots. The hairspring seems nice concentric and the roller jewel seems fine too :huh: However, it is clear that a big part of the problem was somewhere in the balance and @StuartBaker104 may well be right in his observation (even though I didn't spot it).

I also noticed that both hair-springs, new and "old", don't / didn't run freely between the regulator pins and a change in daily-rate causes a slight shift in the beat-error ......... that's something to be sorted later.

First, I will let the movement run for at least 48hrs and see whether the amplitude is on the rise and after that start to do perhaps some hair-spring fine-tuning..... thereafter the re-assembling of the chronograph parts.

Anyways, despite no obvious fault was observed, things start to look a whole lot healthier ........

Thanks for your help :thumbsu:

 

Edited by Endeavor
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@sstakoff ; No, I did not as I don't have any tool for doing so. The balance is of simple design, no adjustments.

58c95a875c115_3133balance.jpeg.55252caeaf389374014ae9941be64d28.jpeg

If you have any smart idea's to check the poise of a balance with simple tools, I would be delighted to hear ...... !

According to the seller, the movement ran fine on his timegrapher before shipping and I can't see any obvious deformations to the balance wheel, staff or bend pivots.......

Edited by Endeavor
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Hmm. Perhaps try a dynamic poising exercise? I attended a lecture on this topic a few months ago. I'm not able to check now, but search for dynamic poising techniques. But, if there is some other defect in the balance it may mask these results. Dynamic poising only requires the balance installed, and a timing machine. No additional tooling.

I suppose someone could have removed and rotated the roller on replacement. Then they would have had to rotate the hairspring to avoid major beat errors. But - this may result in an out-of-poise situation.

Interested in other people's thoughts on this theory????

Edited by sstakoff
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This was a N.O.S. movement. It looked brand new and I don't think the seller has been fiddling with it ...... something must have happened during transport, but there are no evidents to be found and all was well packed.

It's a great mystery what has happened to the movement between these pictures and me receiving it.

Sellers eBay picture;

MT-01.thumb.jpeg.01f72c4f5da3dd5df740c144608f6693.jpeg

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For the new results how far wound up was the watch? my concern is for a fully wound watch in the pendant positions drops to 200° which seems like too much. In other words at the end of 24 hours is the watch even going to be running?

the sine wave effect is usually a transmission problem out around wheel for instance. I also assume you demagnetized the watch? The link below talks about doing a long-term time plot try this see what happens. A lot of times if you have an out around wheel it will show up but you need time to get a nice time plot. if the problem is farther back in the gear train it takes a while for the problems show up so as you're going through multiposition timing you may be seeing and out around wheel farther back being your source of the problem. This is where time plot will usually show these things.

this is also where your dial-up and dial down should be reasonably close to the same and is quite a bit a difference? So with seeing the effect of the gear train causing an issue or is it really a problem of dial-up and dial down?

Then for dynamic poising is not a substitute for static poising although for your modern wheel it shouldn't be an issue. More of an issue for older balance wheels with screws that can be hopelessly out of poise or bent balance arms on bimetallic then you definitely have to be statically placed first. Then of course the watch has to be in good running condition if you're having problems for other issues dynamic poising isn't going to fix that.

http://www.watchoscope.com/manual.html#longterm

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@JohnR725 Thank you for your contribution ! ;)

I spotted a few problems which I couldn't solve yet. To remind the audience, I started tinkering with watches last year January and I'm now doing things I never dreamed of me doing. Changing out balances was for sure not in my comfort zone, now with this watch it slowly has become. Inevitably I make beginners faults, and I have to admit I didn't demagnetize the watch. Thinking a N.O.S. doesn't require one and there were no signs of magnetism :huh:

Current states and spotted problems;

Since I couldn't improve the DU, DD, CU & CD substantial DR differences, I changed out the new balance wheel & hairspring for the old, original one. This time the results were as per the new balance. I made sure that the hair-spring oscillated in a "perfect" horizontal plain. One thing I noticed however, just like with the new balance, that the nicely concentric hair-spring gets "pushed over" or "pushed around" by the regulator. I've been manipulating the hair-spring curvature, which improved the situation slightly, but one can still see the hair-spring moving when the regulator is moved through its range. (Since the old original balance it back in, this situation must have been already "of factory")

Another thing is the balance-wheel end-shake. I noticed, for my feeling, a reasonable play. There are two spacer-washers underneath the balance bridge; 0.05mm and 0.04mm. With the watch running I could take out the 0.05mm, tighten the bridge-screw and the balance was still oscillating freely and still had some play; however in CU and CD, the amplitude dropped significantly (<100).

To recap; the hair-spring / regulator is a problem which I can't solve yet and I lack theoretical knowledge of how much end-shake there should be and what the effects are of "too much" or "too little".

P.O.A; I'll strip the whole watch again, including the main-spring. Clean, inspect and demagnetize every single item (not sure if I can demagnetize the main-spring, perhaps when back in the barrel), re-assemble and test. As per earlier advice, I'll wind the watch fully and let it run for 1 hrs before testing on the Timegrapher.

Please allow me this weekend before reporting back.

Any information about end-shake and / or the hair-spring situation is very welcome.

Regards: Roland.

 

Edited by Endeavor
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Back again !

Stripped the whole movement till the last screw and spring. Demagnetized every single item, screws, bridges, balance assembly, pallet fork, you name it, apart from the main-spring which was too awkward to handle through my demagnetizer, which is build on the same principle as the motor in this internet picture; Demagnetizer.thumb.jpeg.8fdd691e63e1d42dbe0375381e3a1417.jpeg

Inspected every item, re-assemble the movement, re-oiled cap-stones etc. Let it run for 18hrs, wound it fully and it ran one hour before taking measurements. Ignore the timegrapher jump in DD and some other odd off-line dots, that's interference from the computer-fan and at one stage (CD) me moving my hand over the table top;

Dial Down;

3133-DD.PNG.4c45856e911972550211b2aca74c1028.PNG

Dial Up3133-DU.PNG.985bda81f349905b685a2e8c1f98b582.PNG

Crown Up;

3133-CU.PNG.202ddf423fb69c431f0bfe354f141950.PNG

Crown Down;

3133-CD.PNG.4f1d0ad874cec408601493c1ca6c0c35.PNG

I would say this is a HUGE difference and as far as I'm aware off, my procedures didn't change apart from demagnetizing, I didn't find anything wrong and so magnetism seemed to have been culprit.

If that's indeed the case, I can not say anything else that I hugely underestimated the influence of magnetism and for sure will take demagnetizing up as a standard part of servicing a watch.

Considering the watch has just had a full service, the amplitudes look good, the beat-errors look fine (I even doubt the 0.5ms in DU, on the graph it looks better, but I'll re-measure) and the daily-rate spread in the different positions seems acceptable to me. There is still a very slight wave pattern, but compared to what is was ..... that's peanuts.

The chronograph parts, dial & hands can go back on and see how it runs .......

Thank you all for you help and I just learned a great lesson !!

If there are any remarks or suggestions left, I'll be delighted to hear....... :thumbsu:

 

 

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  • 5 months later...
On 3/15/2017 at 10:37 AM, Delgetti said:

I'm doing my first steps in dynamic poising these days and for me this page was very helpful to understand the what and why:

http://adjustingvintagewatches.com/category/dynamic-posiing/

oh in watch school my instructor tried to explain dynamic poising to me and it went over my head after reading this article it all makes sense to me thank you delgetti i know it you def helped me out and im sure you helped out other folks out with this article 

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