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So I am on to my next challenge with my Waltham 1883 restoration project.  I bought a donor movement and removed the bottom balance hole jewel to put in my restoration watch--the jewel was missing.  I cleaned the jewel in lighter fluid and pegged it out.  I also removed and cleaned the lower cap jewel.  Finally I removed and cleaned the upper hole and cap jewel with lighter fluid and peg wood.  Finally, I cleaned and used pitch wood to clean the balance pivots.

 

I put the balance back in the movement, without the hairspring, and used a puffer to rotate the balance.  It rotates freely.  However, when I put pressure on the balance cock, or when I tighten down the screw it stops (video attached).   

I can see just a very slight glimmer of light between the balance cock and the plate (on the left side—with the balance being on the left) as though the cock is not sitting perfectly flat on the plate.  What could be the problem?

To be frank, I cannot tell with confidence whether the donor hole jewel is without problems to my untrained eye.  I don’t see anything obvious under magnification.  Could the hole of the donor hole jewel be too big so that the balance staff pivot is extending beyond where it should and is rubbing against the cap jewel.  Or could it have some other defect that’s causing the drag.  Or is it something unrelated to the jewels?  Should I try and source another hole jewel?

 

Any thoughts on the problem would be appreciated.  Thank you.

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Do you have any end shake when cock screw is tightened?    Ideal end shake its .02mm.

Acts like you have a coned pivot facing a flat jewel.

Is there an end stone to the jewel on the mainplate? 

Bent pivot or unlevelly seated jewel.

 

 

 

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2 hours ago, arron said:

 Could the hole of the donor hole jewel be too big so that the balance staff pivot is extending beyond where it should and is rubbing against the cap jewel.  Or could it have some other defect that’s causing the drag.  Or is it something unrelated to the jewels?  Should I try and source another hole jewel?

The hole jewel should be of a size that allows the pivot to pass through freely, with perhaps 0.005 to 0.01mm of freedom. The balance pivot end should absolutely touch the cap jewel. If your hole jewel is too small then the pivot is resting on the outside of the hole; this can be the case and the balance still spin as in your vid. Then it will bind when tightened.

 

American watches typically had a range of pivot sizes and corresponding jewel sizes. Take it all back apart and try the hole jewel on the pivot, see that it fits.

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After verifying pivot size:

I would put the screw in and slowly tighten it down while rotating the balance. Use good judgement to determine if it is getting too tight.

Sometimes, there’s that spot where the balance clearance is reduced just before tightening the screw, which actually raises the balance side of the cock, in that situation.

Of course, there is always the chance that a previous poor-method “repairer”(aka Hack) bent the balance cock to make something fit. Don’t mess with it unless it’s obviously bent.

Edited by Woolshire
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12 hours ago, arron said:

I should have mentioned that there is no end shake or side to side shake.

It's always nice if you put the hole jewel on the balance staff to make sure it actually goes through before putting it in the watch.

22 hours ago, nickelsilver said:

American watches typically had a range of pivot sizes and corresponding jewel sizes. Take it all back apart and try the hole jewel on the pivot, see that it fits.

I have a link to the pocket watch database you can look at pictures of watches like yours. Your upper balance cap jewel doesn't look right? Maybe it is correct I just can't quite tell what the picture so you can look at their pictures and see if it looks similar.

Then you get a parts list here but as mentioned there is a problem with mass-produced interchangeable American pocket watch parts? Usually they failed to disclose that balance staffs and the associated balance jewels come in different sizes.

For instance my favorite example is a particular Elgin staff 857 comes in four different variations of the staff with up to five different pivots sizes for some of those variations. This is an extreme example but it does show American part numbers staffs for instance usually common multiple of pivots sizes and the part number does not have any designation that covers that. Looking at the reference I have for your watch it looks like three different pivot sizes for the lower hole jewel.

https://pocketwatchdatabase.com/search/result/waltham/17305157

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I agree that the jewel doesn’t look right. Typically, the jewel will be flush with the top of the balance cock surface when pushed down. The screws should be in contact with the jewel body at the cut-outs. Either the cap jewel is too thin or the seat for the hole jewel is allowing it to be pushed in too far. Obviously, the latter would cause your issue

2C0228C7-26AA-47E6-88BD-15FA6D171340.jpeg

Edited by Woolshire
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  • 2 weeks later...

I am back from vacation and back at this PW again.  I installed the top cap jewel from a donor and it did sit flush on top but had no affect on the problem of the balance wheel stopping when pressure is applied.  Still there is that ever so tiny sliver of light between the cock and the plate.  the only thing i haven't tried yet is to trade out the lower cap jewel with one from the donor, but i'm not hopeful that will resolve the problem. Still worth a try.   i did also check that the pivot is going through the two hole jewels.

So i'm now thinking of next steps.  Should i try and buy all four replacement jewels?  is that likely to solve the problem or is it just throwing good money after bad?  Any other thoughts about how to proceed.  Thank you.  Arron.

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On 4/1/2021 at 10:48 PM, arron said:

I should have mentioned that there is no end shake or side to side shake.  i will check the issues raised above and report back.  Thank you.

The oscilator will pick up & run as soon as you create some end shake so shim the cock& mainplate. A trick to adjust the end shake to aprox .02mm is to move the shim in& out or move its position.

In case of additional issues like slight bent pivot or jewel issues, the watch will stop after a few hrs of running.

 

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Thanks for the shimming suggestion.  i put a piece of paper between the cock and the main plate and pressed down firmly on the cock and the wheel did freely spin.  so that experiment leads me to three questions.  1) could the shim be a permanent solution.  i do have some very fine sheets of brass that i could put in and leave--might be a bit nicer than plain copy paper.  ha.  2) does this experiment help to diagnose the problem?  is the balance staff too long?  are one of the pivot jewels sitting too low.  are both cocks bent (as someone above suggested).  3) would anyone be trying to source new jewels to resolve the problem or is that just not worth the effort and money.  Arron.

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1 hour ago, arron said:

is the balance staff too long?  are one of the pivot jewels sitting too low.  are both cocks bent (as someone above suggested).  3) would anyone be trying to source new jewels to resolve the problem or is that just not worth the effort and money. 

The problem is your the one who has to make the diagnostics you're the one looking at the watch. We give you ideas's but we can't see the watch like were holding it in our hand.

You will sometimes find that the balance bridge can be bent. Other times people will put raised bumps where the bridge touches the main plate to put it either on the bridge itself for the main plate they use a graver to do it. Other times they'll use paper shims to raise or lower the bridge if they don't want to bend it.

As far as getting replacement jewels that's going to be interesting? If this was a newer watch you could order the parts but this watch was made? A little more than 100 years ago finding replacement parts is going to be a challenge. Then watches of this time. They usually fit the parts anyway so you're going to have to fit them they won't just pop in. Then there's some other minor challenges?

Out of curiosity I looked up the jewels and the balance staffs. Looks like there are two separate staffs with some minor dimension differences. It also noticed that the pivots can be of differing size depending upon?

Things definitely become more challenging if others before you decided to change things or rearrange things or do any of the creative things they like to do in the last hundred years.

https://pocketwatchdatabase.com/search/result/waltham/17305157

 

Waltham staff drawings 18 size.JPG

Waltham balance staffs variations.JPG

Waltham balance staff.JPG

Waltham balance jewels more than one unfortunately.JPG

Waltham 18 size balance jewels.JPG

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Thank you JohnR725 for the diagrams and tables.  I measured my staff at 5.7 mm (with a cheap digital caliper); a smidge less than what the diagram indicates.  Not sure if that would make a difference.  To my untrained eye the pivots look ok.  

Klassiker, it was difficult to hold the jewel and poke the staff through it.  so i held the jewel with rodico, poked the staff through it and then looked at the rodico which had a pivot mark in it.  so it did go through, although i'm not sure how far and whether it's far enough to avoid the pivot cone from rubbing on the hole jewel

In terms of buying new jewels, I was thinking about this seller from ebay (picture below).  I'm not sure if those will work, or if it will solve my problem.  i wonder if anyone on this forum has purchased from this seller and what their experience was. 

how in the world do you measure the hole size for ordering.  probably another specialized tool.  it's always good to have a hobby where you have a good excuse for buying new tools.  i got a little crazy recently and almost bought myself a watch lathe.  i finally came to my senses after reminding myself that i could barely take a watch apart and assemble it (leaving aside whether the watch even still worked after assembly) so why would i be buying a lathe. ?   

i'm thinking now to try and put the watch back together using the shim to see if the watch will run (oh ya, i still need to try and re-shellac that impulse jewel, almost forgot about that).  then decide my course of action.  

Have a nice evening and great weekend.  Arron.

 

 

 

 

1092121130_balancestaffpivots.thumb.jpg.c2c557735170d9a288752a96f4de5f53.jpg

balance jewel.PNG

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On 4/15/2021 at 9:54 AM, arron said:

  is the balance staff too long?  are one of the pivot jewels sitting too low?

End stones are the bad guys here "pushing on pivot end" , moving the hole jewel wouldn't do any good.

Yes shimming is a solution.

In case you came to this conclusion that cock is bent and like to bend it back, do so ONLY without the balance wheel in place.  Install the cock without balance and  pry the cock up to streighten it.

Good luck

 

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1 hour ago, arron said:

I measured my staff at 5.7 mm (with a cheap digital caliper)

In watchmaking terms, 0.2mm is more than a smidge. That is roughly how much breaks off the pivot. If that is a photo of your balance however, both appear intact. The upper one (right) appears slightly bent. Even a cheap caliper should easily be that accurate, unless it is in bad condition. You might want to check it against a known reference (e.g. bright bar diameter) to be sure.

Looking at your original video again, even with no pressure on the cock, the balance isn't turning freely. You can see how quickly and abruptly it comes to a stop. You say you eliminated contamination, and the parts look clean in your photos, so let's assume that's the case. You checked the pivots pass through the jewel holes and are long enough (the idea with the Rodico was good), but I would encourage you to repeat this check, if you are not 100% sure. At the same time you can check the relative hole sizes to the pivots are OK. A sliding fit is not OK, there needs to be some side-shake. Enough is when the staff sits in the jewel (cap removed) and can tilt very slightly to one side. The textbooks say 5 degrees.

Let's assume for the time being that the pivots are long enough, and the side-shake is OK. What do we have left? Back to your video again, with no pressure on the loose cock. The weight of the unsecured cock itself is enough to press down on the pivot, removing any end-shake and increasing friction. The problem becomes much worse when you press with your finger.

I would definitely shim the cock at this stage. Whether that is a permanent solution depends on what you find out from doing it, and how faithful you want the restoration to be. It will take some time to get right, especially if the cock is not parallel to the plate, but you need to have a small amount of end shake with the cock screwed down tight. Then repeat your test with the blower, in several positions (horizontal and vertical).

In my opinion, it's too early to be buying replacement jewels. You need to diagnose the problem first.

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Dose the oscilator come to abrupt stop in face up( cock down)  position too?  if so then we have reason to suspect a bent pivot.  if it doesn't come to abrupt stop in face up position , I would suspect pivot ends and hole jewels, check them if you have access to high magnification and end stones as well.

 

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Do you have a good known flat steel surface? If we ever had a plate or something like that which behaved oddly, we would put it on a surface table and measure or test for flatness.

With the balance cock, it steps up after the screw hole before continuing on to where it holds the balance staff jewel. If you remove the cock and can place it on a flat surface, you can then work out a way to test the distance between the leg of the cock and the flat surface. from the end to the step and across the cock. If it is bent or twisted, you should be able to find it.

You may need to measure several times to confirm things because as @Klassiker said 0.02mm is a bit in watchmaking.

But as I was dealing with things that weighed X kgs, this method may not work when talking about something this small.

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This is all very helpful information and i'm investigating each issue raised.  I think i am going to temporarily shim it and see if it will run, and if it does it should give me some much needed encouragement.  

Can someone confirm my belief that the hairspring needs to be adjusted/bent outward so that the outer wind that ends with the stone (that connects to the cock--hopefully i've got my terminology correct) actually travels outside the diameter of the rest of the coils and doesn't cut across as shown in the pictures.  the second picture is from before i took the watch apart.  the donor 1883 that i have has a hairspring that does the same thing--which is what got me to questioning whether it's correct or not.

well, i hope everyone had a nice weekend.  Arron.

 

1883 hairspring.jpg

IMG_7780.jpg

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Lower picture definitely is wrong but the upper picture is correct.

What your hairspring is called is a Breguet Overcoil Hairspring. I usually just shorten it can use the phrase overcoil hairspring. the one in the top picture is shaped correctly. It most definitely is supposed to come up and go across the Rest of the coils and it forms a terminal curve that should correspond to the regulator pins.

The easy way to get a clue is to flip the balance bridge upside down loosen the stud screw. Place the balance wheel with the stud into the whole make sure the over coil goes into the regulator pins and see how the whole thing looks. Much easier said than done sometimes.

You definitely do not want to change the shape of the over coil you'll no longer connect with the regulator pins and it can be quite challenging to put an over coil back where it's supposed to be of somebody gets creative

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Just a quick update: getting that hairspring between the regulator pins was a real bugger.  Using a screwdriver i was able to lift the spring into place.  I am going to reassemble now and cross my fingers (the mark of a true amateur) that it will at least tik tok for me.

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  • 2 weeks later...

watch repair doth humble a proud man?

after taking the movement apart a couple of times, inspecting and cleaning the pivots and pegging the jewels, i put it back together (with the paper shim) and viola it took off running.  i was shocked, quite frankly.  i turned it to all sides and it kept running.  i called my 11 year old to come take a look; i needed a witness and someone to gloat to.  so i thought, i better oil 'er up now and she'll run even better (i oiled most of it with a synthetic clock oil and i put some DC Mkote DX paste grease on the escapement wheel.  probably not the right kinds of lube to be using but all i got).  i took out the mainspring barrel and lid and oiled the mainspring.  then i oiled the jewels.  i wound it up and .... nothing.  it no work.  i disassembled and re-assembled a couple of times and still nothing.  I can't think now what the problem could be other than that maybe the grease is too thick for the escapement preventing it from moving with as much ease as is necessary.  I've tried most everything the group has previously suggested.  at this point i'm thinking that i need to get back to some practice watches and improve my skills before coming back to tackle this one again.  so unless someone can disabuse me of the idea, i think i'll put it aside for now.

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8 hours ago, arron said:

i put some DC Mkote DX paste grease on the escapement wheel.  probably not the right kinds of lube to be using but all i got). 

Then nothing would have been better. Unlike a combustion engine a watch can run dry for a good amount of time without damage.

Quote

 I've tried most everything the group has previously suggested.

Have you taken the canonical "watch doesn't run" tests?

 

 

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12 hours ago, arron said:

i wound it up and .... nothing.  it no work.  i disassembled and re-assembled a couple of times and still nothing.  I can't think now what the problem could be other than that maybe the grease is too thick for the escapement preventing it from moving with as much ease as is necessary.  I've tried most everything the group has previously suggested.  at this point i'm thinking that i need to get back to some practice watches and improve my skills before coming back to tackle this one again.  so unless someone can disabuse me of the idea, i think i'll put it aside for now.

this is the problem of an 18 size American pocket watch. It's hard if not impossible to see things that you have to. It's very hard to make adjustments unless you know exactly what you're doing because once again you can't see those things. 18 size American pocket watch is not good choices.

4 hours ago, jdm said:

Then nothing would have been better. Unlike a combustion engine a watch can run dry for a good amount of time without damage.

your choice of grease on the escapement not a great choice. That's meant for really high pressure not for an escape wheel with minimalistic power that has to work with ideally zero friction would be nice. I really sticky grease is a very bad choice. Then strangely enough depending upon the watch they will run just fine try. Not for a long time in other words they are to whatever that if you read them every day drive for weeks months years that would be very bad. But for initial testing no problem. Versus a really sticky grease that is almost the opposite of what you want to have.

12 hours ago, arron said:

at this point i'm thinking that i need to get back to some practice watches and improve my skills before coming back to tackle this one again.  so unless someone can disabuse me of the idea, i think i'll put it aside for now.

yes you really do need to understand how the watch works. Having a watch where as I said it's almost impossible to see things and not understanding really how the watch works. Like do you know how to adjust the banking pins that's critical to getting these to work. What about the garden pin or the depth thing of the pallet fork stones. Checking the freedom of the gear train oh wait can't do that because this is a full plate. Did you look at your hairspring is it flat is a touching anything.

Unfortunately watch repair is not about cleaning a watch and having it right especially if it's the vintage. People been moving things playing with things conceivably changing things including you and they may or may not be right. There are so many things that you have to deal to see and understand and grasp and starting a watchword of sizable part of those things are going to be invisible makes it a really challenging piece.

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i agree JohnR725.  is there a different make/model vintage watch that is better suited to a novice?  i think before i put it aside, i am going to degrease the fork and escapement wheel and see if that has any effect.  i did notice this time that when i touched the fork, when fully wound, it didn't spring to the other side like it did the one time i had it running; maybe that's the problem of having too heave a grease.

JDM, pray tell, what is the "canonical "watch doesn't run" tests".

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