American PW balance Waltham 1890 'Strange' Balance Wheel Behavior

Discussion in 'Watch Repair' started by JayW, Apr 14, 2020.

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  1. JayW

    JayW Registered User

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    This is sort of a follow up from Waltham Model 1890 Setting/Winding mechanism Repair, but about another issue. After finding and replacing the setting slide (and learning which pins go over or under which springs - See the Photos 1 and 2 for the Donor and Recipient movements (I did indeed finally find a donor). I noticed that the Balance wheel movement was odd. Without any drive train - only the pallet fork, it seems like the balance wheel abruptly stops after oscillating a little bit.

    Photo 1.jpg Photo 2.jpg
    Photo 1 Photo 2​

    I am hoping that one of you more experienced individuals might be able to spot something or give a suggestion about what the issue might be, please.


    At first I noticed that it was oscillating well until rotating the movement to the vertical position and I thought it might be the balance shaft. But there wasn't much 'jiggle' at all and the wheel could be started in the vertical position and it would start to oscillate just like when in the horizontal position. I looked at the balance staff and the upper and lower jewels - see photos 3, 4, 5 and 6. (I didn't take a photo of the lower jewel - but it seems pristine.)

    Photo 3.jpg Photo 4.jpg
    Photo 3 Photo 4
    Photo 5.jpg Photo 6.jpg
    Photo 5 Photo 6

    Next I tried to see if there was anything rubbing, but I didn't see anything. I did notice something - when it stopped if I, very gently, touched the wheel, "the right way" it would just and/or start oscillating again. ALSO, if I very gently nudged the pallet fork, it would do the same - as if I was overcoming some 'stuck' condition.

    See the linked video to get a feel for some of this. ( ) The last section shows how it can 'oscillate' a little with the balance cock removed - I did this to see if there was something grossly wrong with that end of the balance staff - despite what the photos showed. Note that I thought perhaps the roller jewel was stuck in the fork sometimes, and while I haven't ruled that out by a direct look of the size of the jewel relative to the fork, (and I do suspect anything can be wrong given the way the setting slide was jury rigged before), but the roller jewel itself looks very clean under a microscope.

    I haven't seen anything like this behavior, in my limited experience and I'd be very grateful for any suggestions and/or observations that you might have.
     
  2. Jerry Treiman

    Jerry Treiman Registered User
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    Without power to the train, there is nothing to draw the fork to bank. If the fork is not against the banking pin the horns may be hitting the roller jewel or the guard pin may be rubbing the roller table. Try this with the rest of the train in place and under power.
     
    John Runciman likes this.
  3. gmorse

    gmorse Registered User
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    Hi Jay,

    The video seems to show that something is rubbing or binding. From your pictures, the lower pivot is decidedly flat, the upper one is rather harder to see clearly but looks very oily, (is that a drop of oil on the tip, or is it the tip itself?), and the overall cleanliness is poor. The picture of the roller leaves the impulse pin out of focus, but the roller itself looks dirty; if the pin and the lever fork are also anything other than completely clean, that won't help. I suggest that you clean everything thoroughly, including the staff jewels, and then try the escapement without any lubrication to begin with. The flat staff pivot(s) are not something you can correct without the appropriate tools, but at least you can eliminate contamination from the picture. Have you perhaps oiled the lever pivots, or allowed oil to get on the balance spring?

    It's been said here many times, but it bears repeating: trying to correct problems on a watch which is not clean is a waste of time.

    Regards,

    Graham
     
  4. JayW

    JayW Registered User

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    #4 JayW, Apr 14, 2020
    Last edited: Apr 14, 2020
    Thank you Jerry and Graham. I'll follow up on these suggestions and get back.

    I am curious; what your thoughts relative to putting a balance assembly (including hairspring and roller table/jewel) in an ultrasonic cleaner at low power? (e.g. a small jewelry cleaner)

    By the way, on the subject of the flat-ish pivot - I do have this Jensen tool (but with only one plate) and am wondering if this can be used for polishing the balance staff pivot. It's just under 2" long (not including the position adjusting rod), the largest diameter part of the 'pulley' is about 12mm and the plate has two tiny holes (is that to insert the pivot?). I presume I would have to remove the hairspring - is that right? (Also, I am awaiting delivery of a Jacot tool. So should I wait for that instead?)

    Jensen Tool.jpg
     
  5. gmorse

    gmorse Registered User
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    Hi Jay,

    I haven't seen one of these before, but it does look like the rounding-up part of a Jacot tool, which is certainly the function you need to correct your flat pivot tips. I'm not so sure that this could be used to burnish the cylindrical part of the pivots, since there's no support to take the pressure of the burnisher. I'd be inclined to wait for the Jacot tool rather than use the Jensen. Whilst it is possible to process a balance in the Jacot tool with the balance spring still attached, I think it would be prudent to remove it to be on the safe side, whatever tool you used. The spring is fragile and once distorted you'd never get it back to its pristine original shape, however much manipulation you do. Just take a careful note of the stud's relationship to the roller and the impulse pin before you remove the spring.

    DSCF6759.JPG DSCF6757.JPG

    The first picture shows the burnishing setup for the cylindrical part of the pivot, (notice the way the pivot is supported underneath on the grooved bed), and the second is the rounding up of the tip. The burnisher itself isn't shown, but this is a piece of hardened steel which has had a fine 'grain' raised across its width, and is used with thin oil as a lubricant.

    Regards,

    Graham
     
  6. Rob P.

    Rob P. Registered User

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    I would pull the hairspring and verify it's centered and flat. One of your pics make it appear that it's not centered over the bridge jewel. that will "pull" the balance off center and cause a lot of drag.

    It is dirty, and there's visible dirt under the cap jewel in the 1 pic, but it should still run. It would take a lot more dirt than what I see to cause it to just bind up as you said it does.

    Pull the hairspring and verify it's centered over the balance bridge jewel and that its flat and centered between the regulator pins over it's entire adjustment range. Clean the staff and jewels and reassemble. If it's still doing the same thing, it's not the staff or jewels it's a power problem.

    You should be able to safely clean everything in the Usonic. I do and have no problems. Limit the time the jewels are in there though, any flaws in the jewels can turn into cracks. If you don't want to risk it, then clean the jewels by hand.
     
  7. John Runciman

    John Runciman Registered User
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    Your video is giving the impression that it's grossly out of beat? Then are the banking pins where there supposed to be?
     
  8. Rob P.

    Rob P. Registered User

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    I finally had some time to watch your video.

    Check the safety dart / roller table clearance. It might be too close.
     
  9. NC Plumber

    NC Plumber Registered User

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    I agree with John Runciman, the watch is out of beat. I'd correct that first, then a good cleaning and see where you're at.
     
  10. Rob P.

    Rob P. Registered User

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    And another thing; verify while the balance and jewels are out that the pivots fit the jewels.
     
  11. JayW

    JayW Registered User

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    #11 JayW, Apr 14, 2020
    Last edited: Apr 14, 2020
    Thank you for the great comments and advice. Here is a summary of some of these and I'd like to show a few more photos.
    1. Without power to the train, there is nothing to draw the fork to bank.
    2. The video seems to show that something is rubbing or binding
    3. the lower pivot is decidedly flat
    4. I would pull the hairspring and verify it's centered and flat
    5. it's grossly out of beat
    6. Check the safety dart / roller table clearance. It might be too close.
    7. Many different forms of it's dirty, clean it....

    Attached are 5 sets of photos.
    Photo A: Better shots of the Roller jewel and another one of the lower pivot. From these I don't see anything wrong with the roller jewel which seems neatly installed and fits in the hole, and I wonder if the lower pivot still looks too flat in this view? (Comment 3 - I can't judge.)

    Based upon comment 1. above, I removed the fork and wanted to see how, just the balance wheel behaved. It seems fine - no sticking and oscillates for over a minute. (I'm thinking that this says something about the balance pivot and jewel hole relative sizes? ) It also appeared that the hairspring seems pretty well centered (at least in my limited experience), even if it doesn't look like it from above on some photos, but I could be wrong. (comment 4).

    BUT I noticed something under the fork - see Photo B.
    Photo B: Someone (before me) seems to have a watch sized jack hammer and carved up the metal. I thought the mountains might be high enough to interfere with the fork. I can't imaging what they were doing. So I scraped the metal that was sticking up off. It is somewhat the worse for wear, but at least nothing is sticking up anymore - see Photo C.

    Well it turned out that the mountains were not interfering with the fork or the roller jewel.
    Photo D shows (maybe hard to see) how the roller jewel sits "high" above the damage. And the behavior with the fork reinstalled was the same as before. So something is still 'sticking' (comment 2). I couldn't see it, but it must be related to the fork, and/or the fork/roller jewel connection.

    So I put the two together in Photo E. While the roller jewel seemed (to me) to be neatly installed, in my limited experience it seems like the roller jewel may be too wide for the fork. I'm not sure, but if it is, then there could be times when the jewel and fork may not mesh quite right? I couldn't figure how to look at the dart/ roller table clearance with the pieces installed (comment 6) - I'll keep trying.

    So, again going back to comment 1, I put the watch back together, and while it took a bit more then 3 or 4 winds, by the fifth wind it started running and it's been running for hours.

    Regarding the comments about it being 'out of beat' - Can you please tell me what you noticed so I can learn how to come to that understanding? Note that the microscope camera isn't that fast and the timing between the wheel and the camera could be like a 'beat frequency', so be careful of that - but if it's something else, please let me know.

    Photo A.jpg Photo B.jpg
    Photo A Photo B
    Photo C.jpg Photo D.jpg
    Photo C Photo D
    Photo E.jpg
    Photo E
     
  12. JayW

    JayW Registered User

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    Hi Graham, Thanks for the feedback on pivot polishing.
    I'm not sure about the Jensen - but I think the holes in the vertical plate are to put the pivot through and that plate supports the weight of the burnisher. I could be wrong about it, but thought I'd mention it.
     
  13. JayW

    JayW Registered User

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    And - here's a video showing how it's currently running - slo mo with maybe better time resolution?
     
  14. Bila

    Bila Registered User
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    What is the build-up of material on the roller table, not another watch that has had the roller table glued on with supa-glue or some other compound that should never under any circumstances be used:???:
     
  15. Smudgy

    Smudgy Registered User

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    Without the power from the train to pull the fork to the banking it is likely that the roller is catching on the roller. It also appears that the roller and fork are in position for the roller to be catching the corner of the fork when the balance abruptly stops. Try running the watch with the train powering the escapement to find out if the problem is just that the fork isn't being drawn to the banking. Is the problem persists check that the banking is correctly adjusted for whatever parts you've swapped with the donor movement. In any case the problem appears to be in the fork/roller interaction in the video.
     
  16. gmorse

    gmorse Registered User
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    Hi Jay,

    The holes are to put the pivots through, but if you apply a burnisher to the cylindrical part of the pivot, a) you can't reach all of it because part is in the plate, and b) there's nothing to support it against the sideways pressure and you'd risk breaking the pivot. Compare with the first picture in my post #5.

    However, the flat pivot, (yes, it is flat), is an incidental matter in comparison with the above. Try and address that and then progress from there. I agree that it's hard to see what's going on between the lever fork and the impulse pin, especially the safety pin in the lever, (it isn't strictly speaking a 'dart', they're on double roller levers), but try and check if the impulse pin and the safety pin are both completely upright.

    Regards,

    Graham
     
  17. John Runciman

    John Runciman Registered User
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    I've attached a picture showing where the balance wheel should be at rest. You will note there is a minor problem with the picture and that is a lot of times people will place the watch in beat by making sure the pallet fork is centered between the banking pins. That assumes that the banking pins are where there supposed to be which they're not always on a pocket watch because their movable. Then it also depends upon how much play there is with the roller jewel in the fork slot. This is where one of those modern cheap Chinese timing machines is helpful as it will tell you if you're out of beat most of the time.

    Then I'm being confused by your photographs? In the photograph "A" the roller jewel is sticking out of the table nicely like it should be but in photograph "E" where you laid the fork on top why is at the roller jewel looks like it's barely sticking out at all?

    Then the photos the banking pins are basically a waste of time as you can't visually look at where the banking pins are to determine if there where the supposed to be.

    wr-1.JPG
     
  18. Rob P.

    Rob P. Registered User

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    Looked at your photos.

    The balance has obviously been cleaned because there's no visible crud on it any longer. Good.

    The pics in "photo E" show the fork and the roller jewel. Sticking up from the fork is a brass pin. That's the safety dart and it prevents the fork from moving except when the jewel is in the fork and the pin is in the crescent relief in the roller table. If that pin rubs against the rim of the roller TABLE it will cause drag. If the roller table is out of round, even a little bit, and that pin is too close it can cause the balance to "stick" when the clearance disappears. This is a condition that can be potentially diagnosed because the balance always stops at the same place.

    There seems to be a lot of movement in the balance in your video when you touch the balance with the black tool. Almost to the point where someone might suspect a broken pivot. That's an indicator that the jewels and pivots might not be the correct size for each other. You have to physically check and verify that. If you have hole size gauge pins, that's easy. If not, pull the jewels and place them on the pivots under high magnification. Properly sized jewels/pivots will allow the jewel to fully sit on the pivot but not rock to the side. The cone supports the jewel to hold it level. Jewels that are too big will allow the jewel to sit crooked on the pivot under their own weight. They're just sloppy and fall to the side. Jewels that are too small won't go on. Pivots that are too short won't stick out of the hole slightly.

    It's out of beat but that shouldn't prevent it from running. It will run poorly but it should still run. It didn't want to run so the beat issue wasn't the problem. That it's now running, and has been for some time, indicates that the dirt was part of the problem. At this point discard all previous "fault suspicions" and begin testing in all positions. If it stops or doesn't keep time, proceed with a new fault diagnosis from there.
     
  19. JayW

    JayW Registered User

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    Graham: Ah - I get your point. I guess that's why on the Jacot tool, the pivot lies above the rest groove? But in the pivot polisher, one might be able to fix the tip (flat part)?

    Bila: Good catch - Is that why it looks "clean/clear". Otherwise you'd see the shellac? But, I'll check on the other side - isn't it the other side that usually gets the shellac?

    John: Thank you for the diagram. Regarding the 'length' of the roller jewel ... I think it may be the angle of the photo - see, for example the difference between the top left and lower left in Photo A. My main point in Photo E was that it seemed that the roller jewel was very close to the same size as the fork. No one commented on this, so I assume I'm wrong and it's okay? Is that right?

    Smudgy: Please see the video in post #13 with everything installed and under power. So it runs, but I guess it still means that the power is overcoming the sticking, but maybe that's okay for this watch, which I'm not trying to "adjust" just yet. (Well not sure if it's okay - see the photos in this post.)

    Rob: Thanks for the idea about the pin contacting the roller table. I noticed the pin was bent slightly away from the table, I'll check if it stops in the same place next time I have it apart.
    I'm not so sure about the 'alot of movement in the balance', a least compared to my other watches (I assume you mean end shake or equivalent)?
    I've been looking for a hole size pin gauge. But I wonder, when I spun the wheel without the fork it seemed fine (kept spinning for over a minute and didn't 'shake'. Maybe this isn't a good test and indicative of whether the pivots fit the jewels? Let me know.

    John and Rob: "Cheap Chinese testing machines" and "Testing in all positions" -- Be careful what you wish for. See these two photo pairs. I assume this is what you meant. Obviously things are not well in all positions, even if it still runs. (By the way it's keeping good time.) I need to read more to understand what the graph means when the movement is in the down position, unless you can help me out here?

    Photo 1.jpg Photo 2.jpg
     
  20. JayW

    JayW Registered User

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    P.S. For pin gauge set - what would be your suggestions for the smallest diameter and what increment between pins.
    e.g. most sets seem to start at 0.011" = 0.28mm and go in increments of 0.001" = 0.025mm. Is this okay?
     
  21. gmorse

    gmorse Registered User
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    Hi Jay,

    Yes, with care it should do that; do you have a bow to rotate it and a burnisher? You'll need these for your Jacot tool as well.

    This is usually a good test and does suggest that the problem doesn't lie with the balance staff itself or its pivot jewels, but moves the focus onto the possibility of the balance spring rubbing or the engagement between the lever fork and the roller being in error.

    Regards,

    Graham
     
  22. gmorse

    gmorse Registered User
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    Hi Jay,

    Staff pivots can be as small as 0.12mm or 0.0047". If you need to measure the diameter of a pivot, a decent micrometer is a cheaper option than the sets of jewel holes which Seitz sell as a 'pivot straightener, but are more use as a measuring tool, (don't go there!).

    Regards,

    Graham
     
  23. JayW

    JayW Registered User

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    Thanks Graham. The Jacot set will come with two bows and burnishers. In addition I got some info from Smudgy on making a burnisher, which I'm going to try.
    Also, I just got a small battery operated motor with a pulley, and was going to build a small stand to use with the Jensen pivot tool.
    I guess the related question is whether it matters if the wheel is going back and forth (two directions - like it would be with a bow), or just one direction (like with a continuous motor or a lathe)? (e.g. should I include a reversing switch on my small motor?)
     
  24. JayW

    JayW Registered User

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    Graham - I meant pin gauge - to measure the jewel hole size. But I take your point about measuring the pivot diameter too !

    (It's true my micrometer doesn't have small diameter spindle. Were you the guy who had an old one with a thin spindle?)
     
  25. gmorse

    gmorse Registered User
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    Hi Jay,

    I think the question isn't so much about the back and forth motion, (remembering to reverse the bow direction in sync, but above all, keep both moving), but more about the fine feel you get with the bow for the way the burnisher is working. A delicate touch is needed, because it's all too easy to go too far and/or make the pivot tapered.

    Yes, that's my old Brown & Sharpe mic.

    Regards,

    Graham
     

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