Amplitude problem in PU position

Muskie 71

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Hello all. My first post. Hope I can get some help. First, the watch, Waltham 18S, 17J, P.S. Bartlett, Model 1883. Replaced balance staff, balance bridge hole jewel, plate pallet jewel. Cleaned, oiled. On full wind with the original mainspring I get an amplitude of ~200 in DU, DD, PL, PD, PR, but in Pendant up position the watch nearly stops, and does stop when not at full wind. Looking between the plates at the movement, the roller table, roller jewel, pallet jewels nothing stands out as wrong. Hoping someone has had a similar experience and found out the correction. Thanks in advance.
 

musicguy

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Hi Muskie 71

Welcome to the NAWCC Forum!

I am going to move your post to the Watch repair section for best answers.


Rob
 

Skutt50

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Welcome to the forum!

There can be several problems causing this bahavior.

I would remove the pallet fork and the hairspring and check that the balance spinns freely in all positions. Is there proper end shake? Listen for any odd noice!

Next would be to carefully examine the pallet fork. Any bent pivots? If you tilt the movement, does it move between its two end positions (with a let down mainspring)? Does it snap between its two end positions if you give it a gentle push (with wound mainspring)?

If the above checks out I would re-install the hairspring and check if there is any interction between hairspring and any other part. Again, listen for odd noice!

If that does not show the problem I would carefully check the guard pin and impulse jewel. Could it bee that they are a tiny bit too close to the balance / pallet fork and in one particular position they don't interact properly?
 
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Muskie 71

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Thank you Skutt50 and Karl. Earlier today I let down the mainspring and set the balance in motion by twisting the movement back and forth with my hands. I then put the watch in the PU position. As the balance came to rest it looks like it's definitely catching on something, but I don't hear any noise. The pallet end shake and side shake seem fine. The pallet does snap back and forth smartly when under power. The pallet pivots look fine. On close examination with magnification it does look like the guard pin is just slightly hitting the roller table. I don't think the guard pin is bent but I will remove it and look at this further. To me it's odd that it would only happen in the PU position for this to be the problem. I have not tried to move or straighten a guard pin so I'll approach this cautiously. I'll report back tomorrow. Thanks again for your replies and suggestions.
 

Skutt50

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To me it's odd that it would only happen in the PU position for this to be the problem.
There is always a tiny bit of side/end shake in each pivot/jewel and even if small, it is there. It can be that in this one position, with gravity pulling just "right", things add upp and it is causing enough problem to halt the movement.

When you check the guard pin also check the safety roller for any left over shellac residue.

You said that you replaced two hole jewels (pallet fork and balance). If e.g. one of these has a hole that is not centered perfectly that could result in a small shift in position of the arbor which could be enough. On some older watches one can actualy see a punch mark showing in which position the jewel was mounted. Specially for balance jewels that are intended to be removed when servicing the watch.........

Be careful when you work on the guard pin. It does not tke much to make it loose functionality and your watch will overbank......
 

Muskie 71

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I removed the pallet and placed the pivot in a pin vise. Then carefully used an arkansas slip stone to reduce the guard pin. It didn't take much since the guard pin looks to be brass. Put it back in the watch and it appears to have corrected the loss in amplitude. I've moved the watch around quickly and haven't had overbanking so far.
The upper screw set jewels in this watch do have nice marks showing the orientation, but the pallet jewel I replaced was on the main plate and it was rubbed in. Under high magnification the pivot looks to be moving freely in the hole so it looks like it's ok.
I did some dynamic poising on the balance and added a timing washer opposite the heavy spot. This did improve the poise but it's not perfect. Also the beat error is too high. More work to do there.
On full wind the amplitude read 244 in the PU position on a Weishi time grapher with the lift angle at the default 52.
I replaced the mainspring and got 273. Slow motion video recorded on a smart phone looks to be in the 290 range. The other positions are all similar. So, happy ending. :)
Thank you Skutt50 for your help and comments. And thank you Karl for pointing out the possibility of the banking pins being the problem. From my limited knowledge and experience I would be fearful of doing more harm than good in trying to adjust them.
 

Skutt50

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Congrarulations so far.......

You tested it in PU position and tht is the position the watch is having when in a brest pocked. You should however also test it in at least DU and DD position.

To make the watch run fine in one position is not that hard but when you try it in various positions that is when the fun begins. The static poising is one thing but what is called dynamic poising is the best. May I suggest you check the timing in various positions and if it differs to much between the positions, try again with the newly added timing washer removed. The timing just might improve!
 

Muskie 71

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Congrarulations so far.......

Thanks for the congratulations and I appreciate the ....so far...
Please excuse my patting myself on the back but I've done more to this watch than any other and it's running quite well for all that was wrong with it.
I started out in this hobby in the fall of 2019. I inherited a few pocket watches that my Dad had collected (one is my maternal great-grandfather's). Early on, I was happy just getting a broken watch functioning again, but as my skills improved I realized I could be doing much more. Right now I get the most enjoyment in taking pocket watch parts and making them whole again. A few months ago I became aware of a blog (adjustingvintagewatches.com) where I first learned of dynamic poising. So now I'm sorta at a crossroads. Do I continue to repair watches to the level where they sit in a plastic cradle in the PU position keeping good time, or do I go down the rabbit hole further. I'm pushing 70 so I have limited time. I've got several projects on the shelf, and I doubt I'll ever get to them if I return to all my previous watches and adjust them to six positions. One wonders what that would really accomplish since these watches will never compete with the perfect time keeper in my pocket right now, my smart phone.
Anyway, I'm rambling on....please comment on how you have dealt with how perfect do you want your watch to be?
Also, what a wonderful hobby the world of horology is!
I'm much indebted to all the information available on the internet and in books.
 

Skutt50

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Nice to hear that you are happy with the result.

As for how to deal with the adjustment I also have a number of watches that I repaired and/or serviced over the years. As you, I would not have time, nor would it be financially defendable, to adjust all to perfection. (Many are of lower class and were never perfect to start with, e.g. they were adjusted to one or three positions.)

My suggestion is to select a few upper class watches to give some extra attention. Some examples would be movements of Railroad grade, high jewel count or a movement with some complications.

Good luck with your new hobby.
 

Muskie 71

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Thanks Skutt50. Sounds like excellent advise. Perhaps I should start with this 17 jewel Waltham. It was adjusted back when it was new. Imagine the slow and laborious process of static poising back then. What am I complaining about!!! :)
 

Muskie 71

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Sorry John, didn't mean to not answer you questions. No I didn't check the poise statically after replacing the balance staff and I should have since it would be a quick way to identify a large imbalance. The amplitude was less than 200 when I dynamically checked the poise.
When I did add a timing washer I wished I had a better pin vise to grab the balance screw. One that was more sensitive to tighten and loosen. Any suggestions on a source for a good one?
Also, if I'm going to take this on I know I will need to remove material from balance screws, not just add washers. Any suggestions for those types of tools? Thanks in advance.
 

Skutt50

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Also, if I'm going to take this on I know I will need to remove material from balance screws
It is not too uncommon to find old movements with screws with a filed down head. Sometimes you find screws that were "invisably" lightened i.e. material was removed from behind the head. I have also come across some where the screw slot was widened/deepened to remove some material.

There are several oppinions on this matter but in general it is suggested not to remove material but to change the screw for a lighter one. The principle beeing not to make any changes that can't be reversed, i.e. timing washers can be removed, a filed screw can't be reversed.

I was lucky some years back and came across a couple of boxes with thousands of new timing screws to choose from. Unfortunately not sorted so it is a guess every time as to which to choose. The different materials used in the screws adds to the equation and I have not found a suitable scale that measures with enough accuracy....

Before this I saved all old busted balances I came across, to use as screw donors.

Which movement you choose depends on what you have in your collection. A 17 Jewel Waltham sounds like a good start.

Good luck with your new hobby.
 

gmorse

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Hi Muskie,
I know I will need to remove material from balance screws, not just add washers.
Before you make any irreversible changes, (as Skutt has advised against already), I strongly recommend that you read this document on dynamic poising by DeweyC.

Regarding the safe holding of balance screws, there are special sliding holders like very fine pine vices made by Bergeon and others but they're quite expensive; search for 'balance screw holders' and you'll probably also find some for sale second hand.

Regards,

Graham
 

John Runciman

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No I didn't check the poise statically after replacing the balance staff and I should have since it would be a quick way to identify a large imbalance.
a lot of things in watch repair require you to follow the procedure if you're going to have success. For instance in between putting the staff in and poising by whatever method you do need to verify that the balance wheel is round and flat. In other words with a truing caliper you half to do that if you do not poising will be a nightmare. This is because the arms are bimetallic if you squeeze them they will bend. so for success in restaffing procedures must be followed an understanding of what you're doing helps immensely. Otherwise you're going to go down a bad path that leads to confusion and has endless problems.

Before you make any irreversible changes, (as Skutt has advised against already), I strongly recommend that you read this document on dynamic poising by DeweyC.
a new
There are several oppinions on this matter but in general it is suggested not to remove material but to change the screw for a lighter one. T
both of the comments above are good and the PDF is good but they all have a problem? The problem is how did you learn watch repair? Even your reference books start comparing reference books they all agree. What happens if you put a group of watchmakers together it asked simple basic questions is everyone on the same page and if not who actually is right and who was wrong or they all right were even all wrong that's the problem.

let's start off with PDF above specifically near the bottom of page 4. do watches have no value or perceived not the value and get played with by children? Or as a kid did you ever find your great-grandfather's watch stuck someplace and look at it conceivably all of that is correct. Now the problem with children and pocket watches typically are there are easy to get into and that is a problem. For instance currently on my bench somebody wants to restore the family peace it's missing the back. It unscrewed and is now somewhere else in the universe. What else happened when somebody was in this watch well the screws are not entirely right and it seems be missing its hairspring and the roller jewel and of course the pivots are broken. So handling by unskilled individual at some point the time in the past weather was children or not is not good for watch. So I'll go with children playing with the watch.not good but it's not always children either that have done that it's basically anyone that has no idea how delicate a watch can be.

Then we get the really interesting statement Used by practice by unskilled workers possibly. We get a different problem here or a different point of view American pocket watches were made in quantity they were made for how many years? This means that between then when there were made and now more than likely they've gone through quite a few hands of people labeled as watch repair people. Where exactly did these watch repair people learn their skills from that becomes the problem. The so-called unskilled workers practicing conceivably are watchmakers in the field right now or their past generations.

one of the problems for past generation watchmakers his education this means conceivably you do stuff because you perceive it's the right thing to do until someone comes along and suggests that maybe it's the wrong thing to do providing you can accept that may beer not doing things correctly otherwise we can end up with multiple of generations of watchmakers not necessarily doing the right thing.

Now let's toss in some additional PDFs at the link below scroll down until you get the section titled Joseph School of Watch Making. This is a training manual for the school they had a school they taught multiple generations of watchmakers I don't know how long the school was in existence but this is their training manual.

You probably want to download the entire thing but let's start off with unit number two truing the balance wheel. At the very minimum verifying that the balance wheel still is true in particular it is round. Bimetallic balance wheels are very easy to get out of round. Typically when you're staffing them and holding them in your fingers you can squeeze the arms moving the arms around totally screws up poise and timekeeping. A lot of times will be out of flat more likely that was caused by somebody inappropriately staffing the watch. So ideally before going on in balance staff work your balance should be running flat and round.

now let's go back to the watch adjustment PDF the very bottom of page 4 all the way through page 5 is it correct? in the section I just quoted several problems occur first we find out that balance wheels get mutilated for variety reasons mutilating watch parts for whatever reason is not desirable. so were all in agreement mutilating the balance wheel is bad. We learn that they were all butchers who did this static poising is the work of the devil but yes I'm exaggerating when it really is is what happens when unskilled workers work on watches. Workers who did not grasp what they're doing static poising is not the work of the devil and unlike the authors point of view static poising can get you really really really close. Static poising is taught in schools even modern schools it's in books probably every single book I have one watch repair comments on static poising.

Let's look at unit five at the link below what does it cover? it covers static poising and it shows the balance under cutter this is preferred as you do not mutually the screw heads. But you will see on cheap watches that well people will file the slots exactly what it shows here. There even was a tool made that will drill out the visible screw head. But not just done by people who read the book every book even done by the factories. Some of the early pocket watches if you look at the screw heads the screw slot is of different depths to correct for poise. So static poising does and can work.

But in an ideal perfect world where no one has ever touched that balance wheel you shouldn't really have to do much for static poising other than verify that the watch is poised. You most definitely should not have to haul out all the screws attempting the poise the balance wheel. This is where for instance putting a timing washer on a screw even though you can remove it later is where you should a slowed down and thought about what you're doing and why you're doing. It's because people either had no idea what they were doing and embraced the teachings of the books or they're just idiots mutilating the watch is not good static poising does work and despite the author's opinion that it's a work of the devil my opinion is you can get really close to you don't have to dynamically poise providing somebody didn't mutilate the watch before you. Also sometimes static poising is a must if you have to start swapping screws and things it gets you really really close even if you are going to dynamic poise because you cannot dynamic poise your way out of a gross mutilation.

Let's look at page 6 notice the references to timekeeping. If you look at timekeeping specifications of American railroad watches yes they exceed Rolex timekeeping specifications. But most important number six on his page you cannot do anything related to timekeeping adjustment until the watch is working very well. in other words if you look at the title of this discussion you cannot do dynamic poising silly you fix whatever the problem is you can statically poise just don't mutilate the watch doing it. But you should be doing any of the poising and tea figure out why are having a problem because all of the poising will be a waste of time anyway.

then I went back through and read the original posters comments and things I assume now that this discussion is come to an end? as the watch is now running perfect or at least the person thinks so and.





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Muskie 71

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Thank you Skutt, thank you Graham, thank you John. I learned a lot today. I hope you all will be willing to help in the future going down the horological road.
 

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