Picture tour of replacing a staff on a Waltham 6/0s wristwatch, enjoy!

DeweyC

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I have written quite a bit. But as I write I realize I am not easily able to say "just press the I believe button", and I do not have the full scientific knowledge to back up my understanding on hand.

I enjoy sharing, which is the reason I originally posted this thread, to share a process that I enjoy as a watchmaker, and that I thought others would enjoy seeing as well. Be prepared, it probably will not be the only time I do this! My intent was never to come here and say "do it my way", but only to share some of the work I do.

I have decided that it is best if I simply say, this is not what I learned in school, and until I am able to be an instructor, that I am able to best write and instruct what I have learned, I should not get on the podium.

So I will though share my background. It is my sincere hope that my credentials help everyone understand that although you may have a different way that you do procedures, I too have my way, and it is the way that I was taught, the way that I understand, and I am recognized for the way I do my work. In no way am I saying anyone is wrong, as I just said earlier, I lack the ability to demonstrate in a way as I learned in school, I can not properly teach static and dynamic poise as I learned. If I can not properly convey my understanding, I can not say your understanding is not right. But I can say I learned differently.

I was Active Duty in the US Navy for 20 years and then I was retired. I joined when I was 17 and a Junior in High School as I knew it was what I wanted to do, and went to boot camp after I graduated from High School and turned 18. While I was in the Navy I started my career as a Data Systems technician specializing in the Link 11 system and ended my career as an Electronics Technician (as the DS rate was phased out), my primary specialty as an IFF technician, but I also worked on GPS navigation systems, etc. I had quite a few NECs. I spent nine years of my career overseas.

Since my Grandfather showed me an American Pocket watch when I was five I was hooked on watches pretty much my whole life. While I was getting close to being retired from Active Duty, I was considering a career in watchmaking. And as you can tell I took that leap. It is not uncommon in America that most professional watchmakers are second careers. In America it is not common to grow up wanting to be a watchmaker, as it is in Europe, and the training infrastructure is simply not the same as Europe for watchmaking. Watchmaking was not a career option for me out of High School so it is also a reason why it is a second career for me.

I applied and was accepted to the Lititz Watch Technicum in Lititz, PA. It was a two year school, with more than 4000 hours of training. The first year concentrated on micromechanics, where I learned how to use a lathe, drilling, hand filing, sawing, hardening and tempering steel, working with brass, friction, rivets, screws, threading, bevels, line finish, polishing steel, sanding, burnishing, boring, broaching, finishes... I can go on and on. I had a clock project first, where I took a common Hermle clock movement and converted it to a straight line clock.

I had to make drawings for all of my early micromechanic projects. One set in a 2D CAD program, one set by hand drawing. They had to be to scale, which means I had to properly measure things. The instructor graded the drawings for accuracy. For the clock I made the bridges, and I learned various ways to set the spacing of the pivots to ensure proper depthing of the wheels and learned the importance of positioning, which allows you to take it apart and put it back together and the pivot holes will be lined up properly every time. One of the pivot holes for example I had to do through math and triangulation only. So swinging arcs with a compass and placing a divot on that point and drilling a hole. I made the pillars for the bridges, one of the train wheels needed a new arbor to meet the endshake requirements of the bridges. I made the click, the dial, the hour markers, the hands, the hubs for the hands. And I made from scratch a Graham deadbeat escapement for the clock. So I made the escape wheel and the pallet and the pallet stones.

Once that project was finished I made a 3/4 bridge for a ETA 6497, and in my case the balance bridge as well. I learned about various ways to transfer holes from mainplate to bridge, turning recesses, boring holes for jewels. I can go on here as well.

I am not a master of micromechanics, but I learned a considerable amount. In the first year I also learned to service quartz watches and quartz theory. And I also learned to service basic automatic watches. The last portion of the first year was learning refinishing of cases and bracelets, the various wheels and compounds used to remove damage, maintain case shape and polish, or appropriate line finish and how to apply it.

The first year of school is fairly intense. There is far more than I mentioned.

Second year of school was dedicated to watchmaking theory and real life repairs and the service of the ETA 7750 chronograph. I learned to vibrate hairsprings, make overcoils, adjust hairspings in the flat and concentric coils. Adjustments. Regulations. Poising static and dynamic. Various calibers, adjusting hammers on vintage chronographs. Real life repairs included case repairs, maintaining water resistance, crystals and gaskets, case tubes and crowns. I bored out ovalized pivots and friction fit jewels in watches to make repairs, I burnished pivots. I wrote up job estimates for the repairs I did for approval. My work was not just focused on modern watches but also vintage... Again I can go on. The second year was just as intense, manipulating hairsprings is not easy work.

I successfully graduated from my school.

I currently have a SAWTA certification and a AWCI CW21 certification for watchmaking. I am level 40 certified with Jaeger LeCoultre. I am level 30 certified with Panerai. I am level 30 certified with IWC. I am level 40 certified with Cartier. I am a level 40 Rolex plaque account in my store. The industry recognizes my certifications, provides me brand and caliber specific training and allows me to perform warranty work on their products, sells me parts and they provide a brand warranty with my work, meaning if I service your watch and it has a warranty error, you can take it to them to be fixed under warranty, you don't have to come back to me. That is a high level of trust right? I started my career focusing on vintage service, before gaining the modern brand certifications.

So after writing my background in watchmaking I can say this. As I learned about Isochronism, rate independent of amplitude, I learned it was a lofty ideal not able to be fully realized. As example friction is an enemy of Isochronism, and you simply can not eliminate friction, so you always do your best to minimize friction.

In school in poising a wheel, I did not once ever move a screw to adjust for poise. Ever. Not static or dynamic. Moving screws is for changing the moment of inertia in a wheel. It does not eliminate a poise error as I understand. The mass of the screw is only moving further away from the center of mass or closer to it, but the poise error, which is a heavy spot in the wheel that can be pulled on by gravity in a vertical position is still there.

To have poise means that the mass of the wheel is evenly distributed around the circumference of the wheel in relation to the center of mass. It has no "heavy spot" for gravity to pull on in the vertical positions. As the wheel moves in the direction of gravity, it accelerates due to the influence of the heavy spot. As it moves away from the influence of gravity it slows down. This affects rate. Eliminate that heavy spot and the wheel has one less influence in the search for Isochronism, gravity being one of the enemies of Isochronism. I eliminate a heavy spot through poise, redistributing mass throughout the wheel, either by adding mass or subtracting mass on the rim of the balance, depending on the type of balance I am am working with, screw vs screwless, or position of the heavy spot, which screws are not always at the appropriate location.

I learned dynamic poising is necessary if after static poising I still have a poise error in the rate of the watch for the positions it is adjusted for during the timing phase of the service. I find the heavy spot by timing methods and I eliminate that heavy spot on the rim of the wheel.

There is much left unsaid here, as I am being extremely basic in my writing.

As moving screws is not a method I have ever used for poising, I can not comment on the effectiveness, and as you can see the methods I learned are different from what is accepted here.

Unfortunately I am not able to fully convey my understanding as I was taught. So I have to conclude with, the way I learned in school is the way that I service a watch, and I don't feel that it is wrong by any significant means. I believe someone said in this thread there is more than one way to skin something...

I will end with my passion in watches since becoming a watchmaker has focused on early watchmaking, as I enjoy all the many ways they overcome the enemies of Isochronism, or how they made advancements in technology. I am always carrying one of my various pocket watches in appreciation for what my Grandfather showed me when I was very young that lead me to this point today.

Springdriven,

Welcome to the group. I received my Wostep Certification in Neuchatel. I know the Lititz program well. I used to host the class for a day at my home. It is a fine program.

In addition to my year at Wostep, I also took courses from Omega in Grenchen and special course taught by Tony Simonin on Precision Timing.

I think if you do some reading, you will see most recognized authors do not agree with you about the purpose of the screws on a bimetallic balance (Jendristki; Gibri, for example). They are there for rough timing and temperature and ultimately position adjustment.

I know well the exercise used to teach making up a balance complete with the vibrating, shaping, colleting and pinning a balance spring. And yes, when a new assembly is made, it is static poised. In fact after the course I sold my vibrating tool and spring material.

If you do not have the pattern for that particular watch, you are shooting the dark. And Tony told us how when he started at Omega it took him 3 months to produce a useable spring. For those who do not know, Tony Simonin was the designer for the Omega 561.

So I decided not to pretend I could make a spring for a precision watch from scratch. And simply making it tick is never my goal. The game is to return it to its original performance.

Now, what happens next in class? You fit your pride and joy balance assembly into your Eta movement right? Then you check positional rates, right? What do you do to correct the positional rates? You use the little cutter you made in class to remove material from the underside of the balance.

The goal of the game (and we considered it such) is to get as close a rate as possible with as few divots as possible.

Now, remove the balance spring and put it on your poising tool. No longer statically poised.

interestingly, many classes do not do this last step. Seems important to me.

The reason for this is that positional adjustments are used to counterbalance the natural escapement errors of the lever escapement. There are several; and I mentioned one, the asymmetric swing of the balance wheel. It travels further in one direction than the other.

If there were no other forces involved. then after static poising there would be no need for positional adjustments.

If you were not exposed to this area of timing, or you forgot, the recognized reference is Watch Adjustment by Jendritski. I understand it is the foundation text for that portion of the programs in all the Swiss schools.
 

SpringDriven

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Springdriven,

Welcome to the group. I received my Wostep Certification in Neuchatel. I know the Lititz program well. I used to host the class for a day at my home. It is a fine program.

In addition to my year at Wostep, I also took courses from Omega in Grenchen and special course taught by Tony Simonin on Precision Timing.

I think if you do some reading, you will see most recognized authors do not agree with you about the purpose of the screws on a bimetallic balance (Jendristki; Gibri, for example). They are there for rough timing and temperature and ultimately position adjustment.

I know well the exercise used to teach making up a balance complete with the vibrating, shaping, colleting and pinning a balance spring. And yes, when a new assembly is made, it is static poised. In fact after the course I sold my vibrating tool and spring material.

If you do not have the pattern for that particular watch, you are shooting the dark. And Tony told us how when he started at Omega it took him 3 months to produce a useable spring. For those who do not know, Tony Simonin was the designer for the Omega 561.

So I decided not to pretend I could make a spring for a precision watch from scratch. And simply making it tick is never my goal. The game is to return it to its original performance.

Now, what happens next in class? You fit your pride and joy balance assembly into your Eta movement right? Then you check positional rates, right? What do you do to correct the positional rates? You use the little cutter you made in class to remove material from the underside of the balance.

The goal of the game (and we considered it such) is to get as close a rate as possible with as few divots as possible.

Now, remove the balance spring and put it on your poising tool. No longer statically poised.

interestingly, many classes do not do this last step. Seems important to me.

The reason for this is that positional adjustments are used to counterbalance the natural escapement errors of the lever escapement. There are several; and I mentioned one, the asymmetric swing of the balance wheel. It travels further in one direction than the other.

If there were no other forces involved. then after static poising there would be no need for positional adjustments.

If you were not exposed to this area of timing, or you forgot, the recognized reference is Watch Adjustment by Jendritski. I understand it is the foundation text for that portion of the programs in all the Swiss schools.
Thank you.

I had a slightly different experience in school, but not by much considering what you wrote.

Thank you for suggesting a book to read.
 
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Jerry Treiman

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This has been a long thread, and I have followed it with some discomfort. However, being primarily a collector and only amateur repairer I have kept my thoughts to myself until now. Most of the discussion has focused on the method of removing the balance staff and issues of poising. The first has been discussed at length several times before and although I have a strong opinion I do not have the breadth of experience to join the discussion with authority.

One procedure, however, has only partially been addressed (e.g. post #15) and I feel I must make a comment. SpringDriven has offered a view of how he has serviced a 6/0 Waltham, but I think it should be noted that this is apparently a late model movement with a solid monometallic balance. For poising the OP has removed material from the balance wheel itself and no one seems to question this practice. If I understand his procedure, new divots might be required every time the staff is replaced. Maybe this is acceptable for solid balances and late model watches where replacement balance wheels may be available. However, for the vintage watches with cut bi-metallic rims that I collect and service (for myself only) I was taught to never alter original parts like this. The balance wheels on most of my watches were matched at the factory and have the serial number of the watch marked on the balance arms. I do not move the screws in the rim as I understand those to have been carefully placed for position and temperature compensation at the factory. I will use the opposing meantime screws for timing if needed. I prefer to add (or remove) timing washers (easily reversible) rather than undercutting the screws if poising is needed. I admit that I do not attempt professional position adjustments.

Would the participants in this discussion agree that one should not make divots in the rims of cut bi-metallic balance wheels? All of my 6/0 Walthams (and other sizes, too) are earlier movements with bi-metallic balances.
 
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SpringDriven

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This has been a long thread, and I have followed it with some discomfort. However, being primarily a collector and only amateur repairer I have kept my thoughts to myself until now. Most of the discussion has focused on the method of removing the balance staff and issues of poising. The first has been discussed at length several times before and although I have a strong opinion I do not have the breadth of experience to join the discussion with authority.

One procedure, however, has only partially been addressed (e.g. post #15) and I feel I must make a comment. SpringDriven has offered a view of how he has serviced a 6/0 Waltham, but I think it should be noted that this is apparently a late model movement with a solid monometallic balance. For poising the OP has removed material from the balance wheel itself and no one seems to question this practice. If I understand his procedure, new divots might be required every time the staff is replaced. Maybe this is acceptable for solid balances and late model watches where replacement balance wheels may be available. However, for the vintage watches with cut bi-metallic rims that I collect and service (for myself only) I was taught to never alter original parts like this. The balance wheels on most of my watches were matched at the factory and have the serial number of the watch marked on the balance arms. I do not move the screws in the rim as I understand those to have been carefully placed for position and temperature compensation at the factory. I will use the opposing meantime screws for timing if needed. I prefer to add (or remove) timing washers (easily reversible) rather than undercutting the screws if poising is needed. I admit that I do not attempt professional position adjustments.

Would the participants in this discussion agree that one should not make divots in the rims of cut bi-metallic balance wheels? All of my 6/0 Walthams (and other sizes, too) are earlier movements with bi-metallic balances.
I agree. I do not touch the rims of bi-metallic (cut or not) balance wheels. It was never to my knowledge practiced. It should not be done due to the forging of the brass and steel.
 
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gmorse

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Hi SpringDriven,
I do not touch the rims of bi-metallic (cut or not) balance wheels. It was never to my knowledge practiced. It should not be done due to the forging of the brass and steel.
I do agree. I'm glad that some concensus has emerged following the discussions here. My intention in raising my initial questions was exactly this, to illuminate an area of watch repair that has been subject to controversy as received methods have evolved over the centuries; 18th and 19th century plain balances were very often filed under the rims, (out of sight), in order to arrive at some sort of poise when first made and possibly in later repairs too. However, I have yet to see any sort of poising tool from this period, so if anyone knows of such a tool or poising practice, please let me know.

DSCF5872.JPG DSCF7167.JPG

If bimetallic rims were filed down, as is sometimes found, it seems to have been the result of rough and ready work, perhaps by workers who had been more familiar with the type of plain balances illustrated above, and often in conjunction with indescriminate filing of the screws as well.

Regards,

Graham
 

DeweyC

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This has been a long thread, and I have followed it with some discomfort.

Would the participants in this discussion agree that one should not make divots in the rims of cut bi-metallic balance wheels? All of my 6/0 Walthams (and other sizes, too) are earlier movements with bi-metallic balances.
YIKES!

Jerry,

Thank you Jerry for asking that this area be better explained since this thread becomes a "permanent" record.

Yes, I agree one does not create divots in bimetallic balances or even follow the recommendation of he who shall not be named to remove material by filing the underside of screws, hollowing out screws with undercutters, or making divots on the face of the screws.

These are drastic alterations that actually should alert the worker that there is a serious fault elsewhere or that the balance is out of true.

Much of this is discussed here: https://www.historictimekeepers.com/documents/Watch Adjustment.pdf

When Springdriven and I are talking about poising by making divots, we are talking about ONLY post WWII balances that are monometallic with a flat balance spring. (I saw the factory method for doing this at ETA and it is an amazing dance of CNC and computer based mass removal location).

This, and an issue related to physics, are why I recommend using timing washers on the light spot to make adjustments and then adjusting with the timing screws on a balance without quarter screws. On a balance with quartering screws (4 timing screws) all position adjustments can be made by those screws alone.

Timing washers are reversible, the methods that rely on removing material are not.

If one thinks this through it becomes clear there is no reason why restaffing should change the factory adjustment. If done with good technique. Removing and replacing the staff has been discussed ad nauseum and is actually a minor part of good technique. Good technique involves removing the balance spring properly, somehow identifying the proper location for the roller jewel (on hamilton 16s dead center when you can read the S/N), replacing the roller in that location, and then truing the balance in the flat and round at 30 X. If you have not removed mass, and the balance os true, it is as left the factory.

Then you also ensure the spring is true and flat when mounted on the balance. We look for the record groove effect which is a joy to see.

If these techniques are followed, there will be none to minor changes from the condition it was in from factory.

However, as we all know, many (most) watches have been altered since the factory.

I have described how in checking for positional rates I found heavy spots that were loaded with washers and that I corrected the rates by removing those washers. The previous watchmaker was using those washers to compensate for issues he/she did not correct during service. This is a fairly frequent occurrence. But at least they used washers.

I often find screws undercut when doing my timing. I replace the pair with uncut screws from a donor balance and look for other screws that have been undercut before proceeding. Then I continue.

Often, screws are altered either by washers or mass removal in widely different positions. This indicates the previous worker did not know how to properly locate the heavy spot to begin with.

To be sure, owners of precision-capable watches (RR grade and up) vary quite a bit. Many are not concerned with the actual performance and indeed it can get pricey to return poorly served watches back to original performance. Most of my customers are people who work(ed) in fields that require precision measurement.
 
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Al J

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In school in poising a wheel, I did not once ever move a screw to adjust for poise. Ever. Not static or dynamic.
I can't speak for others, but for me I wasn't referring to "moving screws" to perform poising operations, but using timing washers under them mostly. This is, I suspect, what you describe below:

I eliminate a heavy spot through poise, redistributing mass throughout the wheel, either by adding mass or subtracting mass on the rim of the balance
As I mentioned before, I don't consider poising a "required" step after changing a balance staff, and I do understand this is how you were taught - it was what I was taught also. But with experience I've learned that if you don't do any damage when removing the staff, and if you are very careful putting the roller and collet back on in the correct positions, it is rarely required unless the balance has already been messed with by others.

As I wrote earlier I just removed a staff using alum (Omega Cal. 601), riveted a new staff in place, assembled the balance back together, and the Delta at full wind over 6 positions was 4.3 seconds (it was 14 seconds previously but then again the staff was worn on one end so I expected an improvement). This movement is allowed to have 30 seconds of Delta over just 3 positions per Omega specs, which is very generous to say the least, but still I consider this a pretty good result for this movement.

Cheers, Al
 

Al J

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Hi SpringDriven,


I do agree. I'm glad that some concensus has emerged following the discussions here. My intention in raising my initial questions was exactly this, to illuminate an area of watch repair that has been subject to controversy as received methods have evolved over the centuries; 18th and 19th century plain balances were very often filed under the rims, (out of sight), in order to arrive at some sort of poise when first made and possibly in later repairs too. However, I have yet to see any sort of poising tool from this period, so if anyone knows of such a tool or poising practice, please let me know.

View attachment 649010 View attachment 649011

If bimetallic rims were filed down, as is sometimes found, it seems to have been the result of rough and ready work, perhaps by workers who had been more familiar with the type of plain balances illustrated above, and often in conjunction with indescriminate filing of the screws as well.

Regards,

Graham
Hi Graham,

Interesting - thanks for posting. Most have likely seen the slots cut in modern balances that are factory poised, but many smooth balances are poised by other means. I can't say I work on watch as old as your examples so I haven't seen this filing method before, but some vintage watches I see are poised using a simple drill from the factory, like these Omega smooth balances:

552_zpsjxwqqsxo.jpg 565_zpsuaasm7lb.jpg

It seems that the transition (at least at Omega) from drilled holes to the more typical modern looking slots cut on the underside of smooth balances happened during the production lifetime of these movements, because later serial numbers tend to have the slots, rather than holes. I've also seen that one the chronometer versions of these balances, there tends to be more poising holes in the balance, which is really the only physical difference between the regular and chronometer grades on these specific movements.

Cheers, Al
 
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DeweyC

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Hi Graham,

Interesting - thanks for posting. Most have likely seen the slots cut in modern balances that are factory poised, but many smooth balances are poised by other means. I can't say I work on watch as old as your examples so I haven't seen this filing method before, but some vintage watches I see are poised using a simple drill from the factory, like these Omega smooth balances:

View attachment 649028 View attachment 649029

It seems that the transition (at least at Omega) from drilled holes to the more typical modern looking slots cut on the underside of smooth balances happened during the production lifetime of these movements, because later serial numbers tend to have the slots, rather than holes. I've also seen that one the chronometer versions of these balances, there tends to be more poising holes in the balance, which is really the only physical difference between the regular and chronometer grades on these specific movements.

Cheers, Al
Al,

Thanks for posting those two photos. They reveal the skill of the person trying to locate the position to correct for the heavy spot. The 565 shows one correction to the initial adjustment. The 552 shows the worker had difficulty. In fact, the 552 would have been rejected in class.

The modern factory method with the slotted milling cutter is an amazing operation. Picture a movement held in a fixture where its rate in the 8 positions is detected (8 vertical positions are more precise for heavy spot ID), then the balance is stopped at the precise location, a cutter is inserted under the balance, removes a precalculated amount of material, returned and then the timing is rechecked. All in about a minute! Next, said the barber.

Not only does this avoid the need for judgment and skill, it removes the potential for damage each time the balance is removed and replaced.
 

gmorse

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Hi Al,
I can't say I work on watch as old as your examples so I haven't seen this filing method before,
I seldom work on anything much later that the mid-19th century, and occasionally as early as the late 17th, so although these are technically monometallic balances they do work on a rather different principle from your examples!

DSC01057.JPG

This is from around 1700 and has been parcel-gilt in the chamferings. It was made by some chap called Tompion. . .

The modern factory method with the slotted milling cutter is an amazing operation.
Dewey, Those machines are most impressive and far beyond the scope of what I do.

Regards,

Graham
 

Al J

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Al,

Thanks for posting those two photos. They reveal the skill of the person trying to locate the position to correct for the heavy spot. The 565 shows one correction to the initial adjustment. The 552 shows the worker had difficulty. In fact, the 552 would have been rejected in class.

The modern factory method with the slotted milling cutter is an amazing operation. Picture a movement held in a fixture where its rate in the 8 positions is detected (8 vertical positions are more precise for heavy spot ID), then the balance is stopped at the precise location, a cutter is inserted under the balance, removes a precalculated amount of material, returned and then the timing is rechecked. All in about a minute! Next, said the barber.

Not only does this avoid the need for judgment and skill, it removes the potential for damage each time the balance is removed and replaced.
Interesting ideas, but I think this assumes that there is only one heavy area in a balance, which is not always the case. Certainly poise marks completely opposite to each other could very well indicate a "correction" to an initial poise that perhaps removed tool much material, but marks not opposite are to me more about correcting more than one heavy spot on a newly manufactured balance.

Cheers, Al
 

DeweyC

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Interesting ideas, but I think this assumes that there is only one heavy area in a balance, which is not always the case. Certainly poise marks completely opposite to each other could very well indicate a "correction" to an initial poise that perhaps removed tool much material, but marks not opposite are to me more about correcting more than one heavy spot on a newly manufactured balance.

Cheers, Al
Al,

Certainly, I am open to a physics analysis of how there can be more than one heavy spot at the start. But it is not clear to me how there can be "more than one heavy spot" unless the second is created by removing too much material on the first correction.

The sum of the forces from unequal distribution of mass around the balance will create a gravity oriented vector that we use as the heavy spot for correction. The heavy spot very seldom is a single point mass (other than a screw on a bimetallic balance).

If the precise amount of mass is removed at that point, the balance will be "poised" ( poised is in quotes because in reality we are talking about dynamic posing to correct positional rates; it will not poise statically).

The force diagram (and the resultant vector) also explains why all positional errors can be adjusted by using only the timing screws on a balance with 4 screws (quartering screws).

The 565 is a good example of a worker who over corrected and then had to make a minor adjustment.

There are times when it does get tricky to id the heavy spot and that is where the machines become much more precise. It is also why checking in 8 vertical positions is the established means for making corrections to positional rates. That 552 is a classic example of taking off too much material and creating multiple new heavy spots with each new "correction". The heavy spot does not "move" in space. It is just that each removal was either in the wrong spot or too much material was removed, causing a change in the vector resultant. (edited because I was asked to clarify).

As I said, work like that revealed on the 552 did not pass in my class. The student was told to take another balance and to try again. Another opportunity to excel as Roy Hovey was fond of saying.
 
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Al J

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Dewey,

Keep in mind that this is a brand new balance, not a previously poised balance that you are working on in a classroom setting. It's very possible that this was posed statically first, then dynamically, and as you note a dynamically poised balance will not poise statically. This in itself can lead to different locations of poising marks - again because they poise differently.

As I said, it was during the manufacturing of these calibers that Omega seems to have moved from doing this with a drill, to using the automated slotting style of poising. Perhaps you haven't seen this before, but here is a clear example of a balance (again Cal. 5656) that has been poised using the technology you refer to, yet has 2 different poising slots:

Poising slots.jpg

I've even seen this on more modern balances as well, so although not something I see on every balance, it is not unusual at all.

Cheers, Al
 

DeweyC

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Dewey,

Keep in mind that this is a brand new balance, not a previously poised balance that you are working on in a classroom setting. It's very possible that this was posed statically first, then dynamically, and as you note a dynamically poised balance will not poise statically. This in itself can lead to different locations of poising marks - again because they poise differently.

As I said, it was during the manufacturing of these calibers that Omega seems to have moved from doing this with a drill, to using the automated slotting style of poising. Perhaps you haven't seen this before, but here is a clear example of a balance (again Cal. 5656) that has been poised using the technology you refer to, yet has 2 different poising slots:

View attachment 649073

I've even seen this on more modern balances as well, so although not something I see on every balance, it is not unusual at all.

Cheers, Al
Al,

It is very likely that mass was removed to time the balance; requiring two cuts equidistant to the heavy spot. The balance/spring assemblies are coupled to produce a sharp peak of efficiency at the design beat rate. It is best to start with too much mass which can be removed than too little (which would require rejection of that assembly).

In fact, it was proved to us in class by experience that it is very possible to remove so much material that the watch cannot be timed to position. This is the reason the game was to equalize the rates in as few corrections as we could.

While a balance too light could be timed in the horizontal positions, it did not have the ability to produce the same rate at lower energy inputs such as when it was timed in the vertical positions.

This lack of a sharp resonant frequency is the reason the work shown w/ the 562 balance was rejected in class. It is getting very close to that point.

The explanation can be found in oscillator theory either in classical spring theory or in electronic theory.

In any case, physics is physics. The example you show does not indicate the existence of two simultaneous heavy spots.
 
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Al J

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Al,

It is very likely that mass was removed to time the balance; requiring two cuts equidistant to the heavy spot. The balance/spring assemblies are coupled to produce a sharp peak of efficiency at the design beat rate. It is best to start with too much mass which can be removed than too little (which would require rejection of that assembly).
So are you saying that couldn't be part of the reasoning for the copious holes in the other balance? If so, why exactly?
 

DeweyC

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So are you saying that couldn't be part of the reasoning for the copious holes in the other balance? If so, why exactly?
Al,

Could it be that the worker was also working on producing the correct mass? ABSOLUTELY!

The interpretation I offered was in the context of the discussion; poise. For the sake of clarity, other issues that come into play in fitting a balance assembly were left out. Nothing unusual or untoward in that.

You offered what you hoped to be an example of two simultaneous heavy spots.

So I had to expand the discussion to include resonance and "Q" theory.

Neither was "Q" theory the foundation of your argument. in any of your posts' specifically post 63. In that post you specifically posited that the two cuts "proved"? the existence of two or more simultaneous heavy spots.

So at that point I expanded the discussion to include how we couple a spring and balance to produce an efficient oscillator.

I had earlier explained how a classical force diagram produces a single vector pointed toward gravity(center of earth) that indicates where the heavy spot to be corrected is located. And that the resultant is very rarely caused by a single point mass with the exception of screws on bimetallic balances. This same force diagram explains why all positional adjustments can be done using on the quartering screws on watches that have them (from post 1910 Hamiltons to Rolex).

I am unable to better explain classical physics. But there is no magic or rhetorical game involved. It just is.

As used in my post, your balance 552 is (and remains) a classic example of what it looks like when one is first learning how to poise a modern balance.
 
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Al J

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Al,

Could it be that the worker was also working on producing the correct mass? ABSOLUTELY!
Thank you for clarifying. That is what I was getting at.

I just want to clarify something because you appear to be looking at this strictly in one manner, which is leading to a lack of understanding of my point. So maybe walking through very simple statements in a step by step manner will help...

With regards to a balance wheel, when it is machined, you believe that it can be made with a heavy spot in one location, but not in more than one location, is that correct?

Cheers, Al
 

DeweyC

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Thank you for clarifying. That is what I was getting at.

I just want to clarify something because you appear to be looking at this strictly in one manner, which is leading to a lack of understanding of my point. So maybe walking through very simple statements in a step by step manner will help...

With regards to a balance wheel, when it is machined, you believe that it can be made with a heavy spot in one location, but not in more than one location, is that correct?

Cheers, Al
Aha. Now we are talking.

What I am saying, is that the heavy spot is the algebraic sum of the distribution of mass on the balance. Of course the mass is never distributed in a homogeonous manner. But the sum vector produce by the sum of the masses reveals the "heavy spot" to be corrected.

While I see your point about the distribution of mass, the practical effect is to produce a single "heavy spot" for correction. The mass may even be greater for 180 degrees of the balance than it is on the other 180 degrees. Understood.

We may well have been talking past each other. Good reason to keep bird dogging an issue.

I never felt we were "fighting", but it did seem we were not connecting. Thanks!
 

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