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Low amplitude questions


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Hi All

I'm still learning the basics.  My latest watch, like all others I've worked on, has low amplitude.  The latest is a  Bulova 11BL.  The dial up amplitude rose from 185 to 220 after the cleaning and dial down stayed low at 170.  

I disassembled and cleaned in a solution of distilled water, ammonia and cascade (recipe from this forum).  Rinsed in alcohol. The ultrasonic would be considered a very low end device for cleaning jewelry.  

I added a new spring but didn't lubricate it. I've read that they come with some type of dry lubricant??  I added a tiny amount of Moebius 8000 to the jewel cups and touched the  exit pallet stone with 9415. I did remove the cap jewels for cleaning and used 8000.  

I've read here that I should strive for 270 https://adjustingvintagewatches.com/pallet-jewel-lubrication/.

Any suggestions?  Also, if the rate is good, is amplitude of 270 still important??

Thank you

Charlie

 

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Possibly something is wrong with either the lower pivot or stone, these have have to be examined with an high magnification loupe, if not a microscope. Check balance end-shake also.
Since you can have the watch running reliably even if it's impaired in one positions, it's really up to you to decide if giving more effort, which can be significant, to this one or move on to the next.

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DU low amplitude normally involves an issue with shakes, balance pivots, or shock proof system.

inspect pivot jewels for any cracks or imperfections. 

check end/side shakes of balance

check balance pivots make sure they are not bent or worn down

check balance wheel and make sure its poised

 

 

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Hi Lc,    The short answer is YES.  270deg is still important. Your reading on the TG is taken in static position.

On wrist, disturbances( from shake of wrist) come and affect the amplitude, thence, the  Dynamic stability of the movement.

 Dynamic stability, means you want the motions of the movement to stay at a constant rate or within an acceptable range.

Assume the balance at rest. A shake will cause the balance to move. On wrist this amount BW move can add or subtract from the amplitude, it will take several pulses for the BW to recover speed, if large enough disturbance may even kill the motion.

Best wishes

 

 

 

 

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1 hour ago, nickelsilver said:

How many rinses did you do? Did you peg the jewels? How much 9415 did you touch the exit stone with?

One rinse. 

I find I'm not able to peg these jewel holes. I bought some real pegwood from a US supplier and whittled it down to a tiny point.  I found the points breaking off in the hole leading to more cleaning.  Any tips?

It's hard to say how much 9415 was transferred.  I've only used it on two watches.  The amplitude of the 9415'd watches is no better than the others.

Thank you

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13 minutes ago, Lc130 said:

I find I'm not able to peg these jewel holes. I bought some real pegwood from a US supplier and whittled it down to a tiny point.  I found the points breaking off in the hole leading to more cleaning.  Any tips?

It's hard to say how much 9415 was transferred.  I've only used it on two watches.  The amplitude of the 9415'd watches is no better than the others.

It is not like any problem (of amplitude or other), can be resolved by insisting on cleaning or redoing lubrication. And, as you found yourself, if one stuffs a soft material like wood into jewel holes, that can cause leaving particles there, which certainly one doesn't want. The mantra of "pegging holes" is to be applied only when there are evident very stubborn residue of dry oil that won't go away with a cleaning solvent alone.

As it was indicated above already, a large amplitude difference between dial up and down indicate either a problem with the supporting stone and pivot - causing friction, or excessive end-shake, causing the pallet stones not to contact completely the escape teeth when in the bad position 

Instead, a problem with the pallets lubrication would happens pretty much the same in either dial position.

 

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Such evidence of fault at jewel and shock assembly, can usually be tested by switching lower and upper jewel assemblies, just to see if the effect moves along with the jewels. This ofcourse is suitable if both jewels looks the same. 

If the effect didn,t move the fault is likely to be with the pivots, if did move!!! with the jewels or chatons. Thats presuming if jewels are not loose inside the housing under shock springs.

Thanks to jdm explanation that end shake on staff and pallet arbor as well as escape, amounts to disalignment at relevent jewels with the escape wheel, or fork horn and roller coming into contact.

I havn,t faced shortage of problem giving advice when it comes to end shake, some members seem unfamiliar with the subject and its relevent issues and how to analyse the test results, even worse the test to see if the combination end shake and pivot length are letting pivots to jump out of jewel hole, in cases the movement is shock protected.

Best wishes.

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Low amplitude can be improved by having spotless jewels & pivots and with the correct lubrication. However the difference is not huge, if you have a watch with really low amplitude 130's/140's for example then there is another fault. Also some watches just by design do not give good amplitudes such as vintage Seiko's. If there is a big difference between dial up and dial down then 9 times out of 10 it is too much end shake. Why this happens I am not sure but to remove it I have found if you move the lower jewel setting a little closer and I mean a little, using a jeweling tool this helps a great deal. But this is after pivots and jewels have been thoroughly checked and are in perfect order.

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It really doesn't take much to zap amplitude. I had a JLC 838, which I've worked on numerous examples of and is a very good running caliber, with about 220 degrees in horizontal. Professional cleaning machine with professional cleaning solutions (I'm a professional), everything looked spotless. Readjusted the escapement, got a few degrees, extra better cleaned the balance jewels and pivots and the roller jewel and fork slot (the roller jewel and fork slot are classic "last thing I checked" culprits), no change. Let it run a few days, no change. I know this movement, I have a routine, it was frustrating as heck. This is a very thin caliber so no cheating slipping a slightly thicker mainspring in- they don't exist. 

Well, the one thing I forgot that's in my normal routine was pegging the jewels, in particular the fork hole jewels. Easily enough done without bothering anything else, and whammo I had 280 degrees. They looked great before, the same after, but there was a good 50 degrees of amplitude hiding in those hole jewels.

Good pegwood is a must, and it's good to sharpen with a razor type knife (we call them Japanese knives, like thin box cutters). Blade needs to be clean too, or you just contaminate the wood and then the jewel. And yes, resharpen between jewels.

Lc130, if you don't know how much oil you put on the escapement that's a pretty good sign that you may or may not have over or under oiled most everything, and overoiling can very much lead to problems like low amplitude. Did you oil the fork pivots?

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Thank you all for your help.  This forum is the only source I have for learning feedback.  Info like this from clockboy helps a good deal  "having spotless jewels & pivots and with the correct lubrication. However the difference is not huge."  A beginner would not know this.  The troubleshooting steps from Nucejoe are very valuable. 

I did not oil the pallet fork pivot jewels. 

I may have spoken too soon.   After letting it run for 30 hours hours, I now get better amplitudes.  These are the stats 6 hours into a full wind.  

DD +156 s/d, 197 amplitude, 0.3 BE

DU -36, 301, 0.5

PD --40, 196, 0.1

PL -40, 220, 0.2

Can it be inferred that either the supporting balance cap jewel or the top pivot (balance weight on it while dial down) has a problem?

The balance shake is just noticeable here 

 

I've read that polishing balance pivots with jewelers rouge and a wood stick can increase amplitude.  Is this generally helpful in most cases?                                                                                                                 

What beat error is good enough?

Thank you 

Charlie

 

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4 hours ago, Lc130 said:

Thank you all for your help.  This forum is the only source I have for learning feedback.  Info like this from clockboy helps a good deal  "having spotless jewels & pivots and with the correct lubrication. However the difference is not huge."  A beginner would not know this.  The troubleshooting steps from Nucejoe are very valuable. 

I did not oil the pallet fork pivot jewels. 

I may have spoken too soon.   After letting it run for 30 hours hours, I now get better amplitudes.  These are the stats 6 hours into a full wind.  

DD +156 s/d, 197 amplitude, 0.3 BE

DU -36, 301, 0.5

PD --40, 196, 0.1

PL -40, 220, 0.2

Can it be inferred that either the supporting balance cap jewel or the top pivot (balance weight on it while dial down) has a problem?

The balance shake is just noticeable here 

 

I've read that polishing balance pivots with jewelers rouge and a wood stick can increase amplitude.  Is this generally helpful in most cases?                                                                                                                 

What beat error is good enough?

Thank you 

Charlie

 

polishing pivots will definitely help but i dont think your gunna see 50 degree increase in amplitude since all pivots and jewels have been clean and oiled. i dont really like the wood with rouge or oil method, i use a sapphire burnisher with some clock oil. but if you dont have $100 to spend on a burnisher use popsicle stick with clock oil.

do this:

with watch running gently press on the top balance endstone with pegwood. keyword "gently." does it stop the balance when you do this? YES? too little end shake. if it does not stop then press harder (not too hard) on the end stone does the balance stop: NO? then you have too much end shake.

also check the shock spring. sometimes i have seen these things way too flat with no "spring" in them cause upper jewel to sit loose in the cock causing fluctuations in different timing positions. when the spring is removed it should slightly pop just like anytime you remove tension from a spring. but not fly off just sorta "pop."

another thing to look at is tightening balance cock screw i had a few movements that werent running right and i added a little more torque to the balance screw and bam was running perfect. if that screw is not properly torqued the top and bottom jewel holes may not be exactly perpendicular and/or giving too much end shake. in some cases slightly removing a tiny bit of torque can solve too little end shake, but in more extreme cases shims will be needed since the balance screw should never be too loose or have too little torque.

Edited by saswatch88
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I flip the end stone over, so the domed surface of end stone faces the pivot. This susally would keep the cone to come to contact with jewel. The test results can be seen right away visually or on TG.

Shock spring should slightly push on end stone, so jewels wont move loosely inside  the jewel housing. 

Once all fault are corrected, proper oil/ oiling enhances the amplitude.

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Well this is interesting!  To me anyway.  It's now running at about 290 both dial up and down.  Vertical positions are about 240.

I tried flipping the main plate jewel over as Nucejoe recommended and this caused it to stop.  Is that common? 

I then recleaned in lighter fluid, reoiled and reinstalled with the cap jewel curved end up toward the spring (the correct way; as it was before flipping it).  Amplitude went from 190 to 287!  Would this likely be attributed to a piece of debris or better oiling or maybe the jewel or spring wasn't seated correctly in the first place?     

I also tried pressure on the balance as saswatch88 suggested.  I did stop if I pressed firmly enough.  I then saw that I could change the amplitude by varying the tightness of the screw.

Thank you both very much!

Charlie

 

Edited by Lc130
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3 hours ago, Lc130 said:

Well this is interesting!  To me anyway.  It's now running at about 290 both dial up and down.  Vertical positions are about 240.

I tried flipping the main plate jewel over as Nucejoe recommended and this caused it to stop.  Is that common? 

I then recleaned in lighter fluid, reoiled and reinstalled with the cap jewel curved end up toward the spring (the correct way; as it was before flipping it).  Amplitude went from 190 to 287!  Would this likely be attributed to a piece of debris or better oiling or maybe the jewel or spring wasn't seated correctly in the first place?     

I also tried pressure on the balance as saswatch88 suggested.  I did stop if I pressed firmly enough.  I then saw that I could change the amplitude by varying the tightness of the screw.

Thank you both very much!

Charlie

 

flipping the jewel will stop the watch if the balance pivots are healthy since it will add to the height and close up the end shakes. Pressing firmly should stop the BW so another sign of healthy end shake. I think you can chock this up to a piece of debris that could have came from anywhere, the air, your oiler, your hand, or it just may have survived the cleaning process. I call these "watch gremlins." They sneak their way in usually by trojan horse(i.e oiler) and wreak havoc without being seen or heard.

practices to avoid this:

-keep all watch parts in a container with a lid when assembling and disassembling.

-wear gloves or cocks. nitrile is best, resistant to static.

-always stab your your tweezers, driver, oilers, pretty much anything you stick into a movement in pith wood. (i.e oil a pivot, stab pith wood, oil next pivot, stab pith wood) you must clean the oiler between each oiling. as you are moving that oiler through the air, it can pick up the tiniest bit of dust that is floating in the air.

-work on watches in a still air environment, no fans, ac, air ducts, in front of windows, any place where there is air flow. I always find that my basement is best, very still air.

- when oiling use very high magnification, 10-15x to see any particle that may have attached itself to the oil

-always dip your oiler on the edge of the oil pool, dust will collect in the middle, and when your not using the oil cup keep it closed.

- constantly take movement and blow with compressed air while your working esp, before oiling, a piece of dust can make its way into movement by just simply sitting on your bench for 10 seconds without cover. do this again when movement is fully assembled.

none of these are guaranteed solution but will definitely lower the risk of contamination 

Edited by saswatch88
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Note the gap between the jewel and endstone.

Short pivot wont reach the endstone, so the staff can move laterally towards the endstone to the point that the cone section of the staff rubs on the jewel, thereby increasing friction which then impedes the balance wheel thence !ow a plitude. 

Flipping the cone section towards the pivot, fills the gap. Preventing the said fault from develpoing.Watch_jewel_bearing_and_capstone.svg

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All faults due to endshake, stemming from short staff or not, can be better shown on this diagram. 

The balance stopped as you fliiped the endstone, that means the dome face pushed on the staff, keeping in from turnuing. So the pivot on that end is not short.if staff was short the dome will compensate for it, dome will fill the gap.

If " gentile " push on endstone stopped the balance wheel, we can easily conclude that staff is not short, the staff must have been sticking out of the jewel hole and inside the gap, indicating the endstone reached and pushed on the pivot as we pushed down.

Please don,t hestate to ask any question, to understand  end shake. 

Best wishes

Why is end shake important to know.  Answer, short staff is common because  during years of operation pivots wear short. 

 

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1 hour ago, Nucejoe said:

Note the gap between the jewel and endstone.

Short pivot wont reach the endstone, so the staff can move laterally towards the endstone to the point that the cone section of the staff rubs on the jewel, thereby increasing friction which then impedes the balance wheel thence !ow a plitude. 

Flipping the cone section towards the pivot, fills the gap. Preventing the said fault from develpoing.Watch_jewel_bearing_and_capstone.svg

Thank you.  The watch now looks great on the time grapher.

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