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7S36 Endshake Problem


jdm

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I can't make sense of this.

A brand movement, was not keeping good time and had irregular timegrapher pattern. Removed balance and palled fork, re-oiled jewels and pallet stone faces. When replacing the balance I have the same symptoms as when an cap jewel is upside down, that is as one tightens the balance cock the balance stops, and amplitude is very small. But the end stones are installed correctly, I've checked them, removed and replaced like 5 time. Tried  also without pallet fork, there is no end-shake.

How could be that the same balance was at least running before taking things apart? Could be that a pivot got bent? I had no accidents when removing an reinstalling.  

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Failing to run when tightening up the balance dock is a sign of dirty balance jewels. Remove the jewels and clean them again. Clean the balance again. Instal without jewels and inspect them as they try to run...Seiko are good as they will do their best to run, I've had a few ticking even with both sides of the jewels not installed. With the balance installed look at the pivots as the balance swings...if looks good dab them with rodico and install the squeaky clean jewels. 

Also is the hairspring sitting correctly? ie flat and sitting level in the regulator pins? Worth checking.

 

Anil

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55 minutes ago, vinn3 said:

the  balance staff should have enough "end shake"  such the cock can be "fully tightened" and still have  end shake.   vinn

Correct and that is what I can't understand, if was OK before, it is not after. Replaced balance complete and still no go. I'm going in rounds and rounds.

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Yes and the current situation is that I'm swapping over 3 movements, 3 balances of which one is brand new, and none is now running even a tick, with or without balance jewels! Exercise for perseverance.

Edited by jdm
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The reason I focussed on dirty pivots is the fact that the watch was running prior to being dismantled. It. Could be some dirt got lodges in the pivot holes..

JDM, have you installed the balance without the pallet fork to see if it swings freely? It would be preferable if you can install it without the wheels and bridge...that way you can really see how it swings.

Anil

 

 

 

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On 6/26/2016 at 9:27 PM, jdm said:

Yes and the current situation is that I'm swapping over 3 movements, 3 balances of which one is brand new, and none is now running even a tick, with or without balance jewels! Exercise for perseverance.

If you have tried various balances without luck have you considered the remaining train wheels, mainspring barrel etc ?

If the train is free running then that eliminates one thing, if under mainspring tension the pallets move with gentle push of peg wood then this eliminates pallet staff or other issue. Always start from one end and work to the other eliminating each until all is working correctly, like so >

Mainspring > Drive Train > Pallets > Balance

If there is a fault with the preceding parts of the movement then no balance you use will work.

 

If the issue is with the balance wheel area then you must eliminate all the possibilities that remain, such as >

Jewels

1) Are jewels clean and undamaged - No pivot wear/debris/dry oils etc

2) Are the jewel seats/fixed jewels damaged or blocked ?

3) Are jewel blocks at correct Height or have then been knocked out of position ? ( if applicable )

4) Are shock Springs correctly installed and correct orientation ?

Balance Wheel

1) Is hairspring flat and concentric ? Is there kink or sticking of springs/magnetism ?

2) Is the staff true, or bent pivot ?

3) Dry oil stuck to pivot tips ?

4) Is the rim true or bent ( you can check this by removing hairspring and placing back in mainplate with cock )

5) Is the roller damaged/fitted correctly ?

6) Is the balance cock jewels correctly fitted or are they out of position ?

7) Is the roller table catching the lower shock area preventing motion ?

8) Is balance hack ( if applicable ) correctly positioned or blocking ?

Cock/Bridge

1) Is the cock/Balance bridge true or is it bent ? ( fitting the balance to main plate if no motion, raise cock with tweezer gently, if motion presents itself, then cock may be untrue )

 

I don't want to come across as telling you how to suck eggs but i face similar issues week in week out and i have to go Sherlock Holmes on the movements i service ( elimination ) and finding the answer is always a case of elimination. There is always a cause or causes, you just have to find which one or many there are until you can solve it.

MrBeat

* As a side note ive often found with seikos that dont want to chooch the pallets/escape wheels are defective

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11 hours ago, jdm said:

Thanks MB. Puzzling as it can be, I've checked all these again and again. I took a break for now but will go back at it asap.

That's the best thing to do. Sometimes you struggle with something and end up putting it away for a while. When you come back to it...voila!...no problem!

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To be one the safe side, I took apart the train, cleaned and oiled it again. With a little patience the movement started running again with a feeble amplitude, maybe 90", so to just give a snow storm on the machine. Did again all type of tries, loosening balance cock screw, etc, replaced palled fork, etc, but nothing helped.

Then out of desperation I started poking on the regulator arms and made an interesting discovery, When the tip of the arms is pressed up or down the amplitude improved dramatically. At one point I got 230" and a regular pattern, but as soon I release pressure the balance would slow down again. Especially pressing up the regulator arm was effective, but at one point it was ticking pretty good with the end stud inclined toward the center (?!?).  Doing these tricks had the the predictable consequence, the regulator ring popped off and in trying to put it back I messed up the umpteen hairspring. Took another balance, balance cock and regulator pin and was back to square one, poking the arms improved things but never to normal working.

So I'm pretty sure that's something in the angle / geometry of the jewels causing the poor amplitude, and given the symptom I suspect that happened to me before many times with these movement. Lesson learned, but I still don't know how to fix it.

 

 

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Yesterday I gave another attempt and the conclusion to which I've arrived (sorry if I'm stating the obvious) is that these movements can only function (meaning having amplitude above 200 deg.) with a perfect hairspring, which is able to deliver its elastic properties, Otherwise the balance swings only because of the mere action of the pallet and does not exercise any isochronous action. The most important part from the end to the outer coil, and it also the one most easily deformed during handling, not to mentioned manipulation. Probably when I was poking on the ends I was just temporarily bringing it back into an acceptable shape. I continued on this path and was able to grab the hairspring by the dog leg, experimenting with the smallest amount of movement, there was a large variation of amplitude on the timegrapher. Alt some point realized that the hs was rubbing on the balance spokes, I attributed this my poor manipulation attempts when the edge of tweezers was not perfectly vertical, hence directing the hairspring away from its plane. I could't not correct this defect and called a day, I will need more balances and more even more respect to them.

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