In search of power

Discussion in '400-Day & Atmos' started by KurtinSA, Mar 18, 2019.

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  1. KurtinSA

    KurtinSA Registered User
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    I've been making progress this past year or so. Having purchased some tools, a lathe, developed better processes, I've moved up from a 50-50 shot that a clock will work when finished cleaning to towards a 75-80% chance that things will work out. Quite the learning curve.

    But this latest clock, the Heco I mentioned in another post, reflects the situation I usually find myself in. The clock will run but weakly. I realize that over swing is the goal, but that depends on how much power can be imparted to the pendulum. This clock is only rotating about 180 degrees and has maybe a 20 degree over swing. That's without the motion works installed. I feel that if I were to add the motion works, the clock is bound to stop running.

    So I don't really know where to look for more power. I'm getting good snap of the EW teeth on the pallets...to me this reflects the minimal friction in the going train. That's the first thing a usually look for. The anchor pin is centered in the movement back and forth and the EW teeth are slightly starting down the impulse face when the pin in vertical. These all seem like "must haves" for a good running clock. I can fit a piece of paper between the fork tines and the anchor pin. I know about fork position in that lowering it results in less rotation but more over swing. I haven't experimented with that yet primarily because the total rotation is already on the lower side in my opinion. If I had a healthy total rotation, I'd easily sacrifice that for more over swing.

    So what contributes to a health amount of total rotation? The EW wheel or really when the tooth comes off the lock face literally "falls" a small amount as it meets up with the impulse face. That jolt of the tooth onto the impulse face pushes on the pallet which moves the anchor pin which then pushes the fork thus twisting the suspension spring. This jolt has to come from the power supplied by the mainspring through the train to the EW. Is that the big contribution to rotation of the pendulum? How can that be improved so that rotation improves?

    What are the physics of the escapement that contribute to a powerful running clock in terms of rotation? While I'm beginning to feel more confident in basic overhaul of a clock, I'm at a loss as to how to help things run better in terms of power to the pendulum.

    Kurt
     
  2. sjaffe

    sjaffe Registered User

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    One component contributing to the amount of pendulum ratio is the torque of the escape wheel. The power source is the mainspring and the torque from this source transfers to the escape wheel via the time train. The torque transfers via the gear ratios, so for these clocks the high torque/low speed of the barrel translates to low torque/high speed at the escape wheel. Different movements have different gear ratios in the train and this could account for why some 400 day clock pendulums have more rotation than others. However, if you have two clocks with identical train ratios but one has a higher rotation than the other, it could be because there is higher torque at the escape wheel in that clock. The difference could be train friction or mainspring condition. I am not considering post escape wheel differences such as fork height, fork/pin spacing, etc. That's my speculation on what is happening.

    Stan
     
  3. KurtinSA

    KurtinSA Registered User
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    Thank, Stan. I wish there was a way of measuring that torque!

    One thing I was thinking about and forgot to mention...what is the consensus on the fork position on the suspension spring, specifically should the fork be as close as possible to the anchor pin or farther away from the pin? There is some slight movement available on where the fork is clamped to the spring. I suppose that for a given force being exerted from the pin onto the fork tines, the larger the distance the greater the twist applied to the suspension spring. Force * distance = torque.

    Kurt
     
  4. sjaffe

    sjaffe Registered User

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    I had a theory that bending the anchor pin might translate more force to the fork and hence yield more rotation, but haven't concluded if this is true or not. You can see some examples of anchor pins that are bent in Terwilliger's book.

    You can measure torque using a fish scale. I acquired one to do that some time ago but other things preempted making the measurements so far. I think you can find other postings on the MB regarding this. My plan was to wrap fishing line around the mainspring barrel and connect the other end to the scale. The scale reading in ounces multiplied by half the diameter of the barrel yields the torque.

    Stan
     
  5. KurtinSA

    KurtinSA Registered User
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    OK...I thought we wanted to know the torque at the EW...more difficult to measure.

    Kurt
     
  6. MartinM

    MartinM Registered User

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    There really is a lot going on with these clocks. And so many places where power gets robbed. If you've cleaned/polished your pinions and lightly broached the plates, the problem is usually in the escapement geometry or the fork/pin alignment.
    Make sure the pallets are nice and shiny. You could also try polishing the fork and pin
     
  7. sjaffe

    sjaffe Registered User

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    You can infer that from measuring the torque at the mainspring barrel then factoring in the pinion/wheel ratios in the train to get to the escape wheel. The ratio for computing the torque is the inverse of the one used to compute the speed from the barrel to the escape wheel.

    Stan
     
  8. KurtinSA

    KurtinSA Registered User
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    The focus should be on the impulse given by the EW teeth to the pallet, right? After all, it's named the impulse face. When the tooth literally drops onto the impulse face, isn't that the largest input to pendulum rotation? How much more input to the suspension spring is there with the tooth sliding down the remainder of the impulse face? Seems to me by that time, the push on the fork (and thus the spring) has taken place and the remaining force of the going train pushing on the impulse face as it slides is so very low relative to the stiffness of the suspension spring and any twist being resisted by the heavy pendulum weight at the other end.

    I haven't spent much time polishing the fork tines or anchor pin...would have to look into how to do that. As for the pallets, they usually just get washed through my process...haven't really looked at polishing them. What are some ways you guys do this?

    Kurt
     
  9. Bod

    Bod Registered User

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    My thoughts, try lowering the fork as low as possible on the anchor arm, this will give maximum over swing. The total rotation needed varies between makes, some much greater than others.
    See how long the clock will now run. The longer the better, more than a week, winning, less than 1/4hr, more power needs liberating.

    Bod
     
  10. MartinM

    MartinM Registered User

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    "Polishing" pallets is above my pay grade, as well. I was just saying that the drop and impulse face should be clean and (Hopefully.).. Shiny.
    As for impulse... The act of the EW tooth sliding across the pallet's impulse face is what imparts the impulse to the suspension, through the pin and fork. The drop is not putting power into the system. it's taking it out. It happens so fast that it is a small loss, though. And it happens at point where the system is in a more or less neutral state. As the pendulum swings through overswing after the drop, it's setting up the impulse phase to come at a time when it will impart the most prolonged force into the suspension (The sliding across the impulse face).
     
  11. sjaffe

    sjaffe Registered User

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    I believe the pallets are quite hard and generally don't require any polishing. This is not the case for traditional anchor style verges in swinging pendulum clocks. These clocks have much higher beats per minute, so the pallet faces get much more wear. These movements also have more power than a 400 day clock, which also contributes to pallet wear.

    Stan
     
  12. KurtinSA

    KurtinSA Registered User
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    Martin -

    I realize the drop off of the impulse face means little in terms of rotation. The drop I'm talking about is the drop off the lock face onto the impulse face. I visualize the lock face as a continuous line/curve but right at the knee of the two faces, the tooth literally drops due to the train torque/force and only stops when it hits the impulse face. Isn't this a significant action in terms of impulsing the suspension spring? I guess there's additional force as the tooth continues to slide down impulse face, but the dynamic action of the transition from the lock face to the impulse face seems important to me.

    I'm trying to get a sense of where the forcing function is coming from during the escapement so I can figure out a way to assess the clock and look for ways to improve the forcing function to get more rotation. In swing of the pendulum from one side to the other, the point at which the EW drops are going to be relatively fixed so the amount of over swing really represents the power available in the clock. More power makes for more over swing. How to get or maximize the power? That's where I'm coming from.

    Kurt
     
  13. sjaffe

    sjaffe Registered User

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    Your "forcing function" is when the tip of the escape wheel tooth rides along the impulse face. This is equivalent to the push stage for the playground swing The anchor moves from two forces: the simple harmonic motion oscillation of the pendulum and the impulse provided by the time train. The latter is the one you want to optimize for maximum rotation.

    Simple analogy: playground swing. If you lift the swing up and let it go, it will swing for a little while, but every time it comes back a little lower until it stops. This is equivalent to when people post here saying "my clock only runs for a few minutes". There's no (or insufficient) "push". Now if someone is standing behind the swing and gives it a push, it will keep swinging. If they only give it a little push, it will swing, but not very much. If the pusher is standing back far enough so that he can't reach the swing because it isn't swinging back far enough, the swing will eventually stop. This is equivalent to "over-swing" for the torsion pendulum. Now if the pusher pushes a little harder, the swing swings out further and continues to swing. If the pusher increases how hard he pushes, the amplitude of the swinging increases. So that's why you want more power transmitted from the mainspring to the suspension spring to get more rotation. But you need some minimal amount of over-swing or you won't sustain oscillation.

    Hope that helps,
    Stan
     
  14. mauleg

    mauleg Registered User
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    In his book, "Repair and Restore your 400-Day Clock", Joseph Rabushka states:

    "The ideal position (height) of the fork is just above the point where flutter occurs" ~and~
    "Make sure that the anchor pin is deep into, and as close to, the base of the fork as possible. This enables the maximum force of impulse from the anchor pin to be transmitted to the fork."


    I use MAAS polish (basically the same as Simichrome) for the anchor pin and fork. I'll also use it on the pallets if they show signs of corrosion or ingrained contamination. A cotton swab works well for this.

    Two things I did not see mentioned are suspension spring strength and beat. Some clocks, for reasons of their own, will run better (and keep better time) with a slightly lighter or heavier suspension spring than specified in the book. Also, even if the beat seems perfectly balanced, tiny tweaks one way or the other can make the difference in terms of increasing overswing.
     
  15. KurtinSA

    KurtinSA Registered User
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    Stan -

    OK, so you're saying that the push/slide down the impulse face provides the force to keep the pendulum swinging. And that the amount of power from the mainspring reaching the tip of the EW tooth is what determines that. Sounds like you're discounting that initial impulse from the tooth falling off the lock face onto the impulse pallet face. I would have thought that was important.

    So, assuming that if all is correct with the escapement in terms of anchor pin movement 4 deg left and right, pin centered vertically when the tooth is part way down the impulse face, then the thing that is going to control the rotation is the going train torque strength....nothing can be done to tweak the rotation. Of course, fork position is important...higher results in more rotation at the expense of over swing, lower means more over swing and less rotation. As for power to the escape wheel, the only thing I go on is that I can get the EW to begin to rotate after only a couple of clicks of the winding arbor...that should demonstrate a reduced friction in the going train. I typically don't measure my mainsprings when servicing a clock...I'm assuming that it's the right spring and hasn't reach a set state. From a cost standpoint, I'm a little reluctant to just replace mainsprings unless there's a reason to. Note here, I'm doing these clocks for myself...if I were doing this as part of a business, I might think otherwise.

    Kurt
     
  16. KurtinSA

    KurtinSA Registered User
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    mauleg -

    Thanks for that...I read Joe's book but it's been a while. If he's correct, that is something that I could change on this current clock issue. Right now, the fork base is pushed towards the suspension spring meaning the base of the fork is pulled away. I can loosen the clamping screw and slide the fork more towards the pin.

    As for beat, I take great pains to get that as close as I possibly can. I have found that parameter to be critical to getting a clock to run.

    Regarding the suspension spring, I don't choose the spring the get the clock to run better but rather choose it so that I get the proper number of beats in 60 seconds. My experience has been that the thickness when coupled with the regulation capability on the pendulum is the only way to achieve sufficient time regulation. A thickness change of just 0.0001" one way or the other can make it impossible to regulate the clock. So, that has been my goal when choosing a spring...consider what is in the book but eventually find the one that allows me to regulate the clock.

    Kurt
     
  17. whatgoesaround

    whatgoesaround Registered User

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    I noticed that you said you can slip a piece of paper between the fork and tines of the fork.This needs to be a tight fit, just enough to allow the fork to move freely and not much more.
     
  18. victor miranda

    victor miranda Registered User

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    wow, that is a lot of advice.
    when it comes to the practical what I do is lower the fork until the clock runs
    or I run out of lower room....
    I also check that the fork never holds the pin.
    this happens near the ends of wide swings.
    and I like deep locks
    what ever else is true, I am pretty sure it takes more power to run a heavier pendulum.

    There are a lot of ways to think this through.
    I am not certain of the right way to say some of what I have as conclusions
    I find it helps to think of leverage as being powered from the EW
    the pin will shove the fork harder as you get the fork closer to the verge.
    the same is true as you move the pin closer to the SS.

    there are consequences for those adjustments...
    it will shove for less time.
    when the spring recoils the pin... too much shove, I think.
    though that may also be an out of beat issue.
    Getting the shove at the correct time and in beat are much the same.

    sjaffe's comment about a swing is a very good analogy.

    victor
     
  19. MartinM

    MartinM Registered User

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    The swing analogy makes more sense if you pretend you're not pushing the rider, but helping them swing by pushing and pulling the rope/chain near where it attaches to the frame at the top. Or like a bullwhip. You have to begin the swing that creates the 'crack' while much of the material is still moving in the opposite direction.

    Moving the fork anterior or posterior (front or back) on the suspension spring won't change the geometry of the system.
    Moving it up or down on the spring does. As does moving (bending) the anchor pin closer or farther away from the suspension spring. That bending is what @victor miranda was referencing.
     
  20. KurtinSA

    KurtinSA Registered User
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    Seems to me that bending the pin or moving the fork towards the pin accomplishes the same thing. I'm going to try this on my clock in a bit and will see if I notice anything. The amount of movement in my case will be about 1 mm or so.

    As for the swing analogy....there's one thing that might be different. In the escapement, the push on the fork is not with the "material is still moving in the opposite direction" if I understand what you were saying. In our case, the pendulum is already swinging towards to the other side, speeding up slightly as the spring unwinds. The proper push needs to start just prior to the pendulum reaching the "neutral" position. In that way, we can couple of the effects of gravity with the push on the fork/suspension spring to get the most power. If this push happens after the pendulum reaches the center "neutral" position, then we lose a little bit from the escapement because we're starting to push "uphill" or against gravity.

    Kurt
     
  21. MartinM

    MartinM Registered User

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    Moving the fork front or back on the spring doesn't change the distance from the pin to the spring. It just changes the place on the fork where the pin makes contact.
    Your last few sentences are spot on. And if you rethink the whip analogy as it applies to these clocks... The point where the impulse is complete and the EW moves to the other pallet is the point where it's imparting power to the other direction. Well before the pendulum has even completed its swing in the 'old' direction. It's not allowed to put that power into the new direction until the pendulum reverses and allows the EW tooth to hit the impulse face. If you swing a whip at something and don't begin the rebound swing in the opposite direction before it makes the full trip, all you get is a 'slap'. Not the more powerful 'crack'.
     
  22. KurtinSA

    KurtinSA Registered User
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    Not sure how much power is being imparted when the EW falls onto the next pallet. The tooth falls onto the lock surface which is the shape of a circle. As the over swing continues, the tooth slides a bit on that circle. I'm not see where there's any substantial power being applied.

    I think you're right on moving the fork in/out. I wonder what Joe's point was when he wrote that in his book.

    Kurt
     
  23. MartinM

    MartinM Registered User

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    You're right about the lock face imparting no power. Like I said in my OP, it's actually a net loss of power when the drop occurs.
     
  24. KurtinSA

    KurtinSA Registered User
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    #24 KurtinSA, Mar 20, 2019
    Last edited: Mar 20, 2019
    Well after all my fiddling, the clock just won't run. I've lowered the fork as well as raised the fork relative to the repair guide. It just doesn't have enough over swing to run. Hence my search for power.

    If there was any clock to submit to the guru to go over and find out what I've done wrong, this would be it. I just have no clue as to what the problem(s) could be. I've toyed with the idea of changing the main spring...that's a lot of effort for a "what if". I've looked at enough escapements so have an idea of how well the escape wheel "snaps" as it drops off the pallet and hits the next lock face. This one sounds and looks good, so I'm having trouble thinking it's the main spring.

    Kurt
     
  25. victor miranda

    victor miranda Registered User

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    your description of the action of the EW and verge make me think you have enough power.

    when you move the pin does it snap over on every tooth and lock on the pallet?
    on the Schatz 53 it is 15 teeth to check...

    I think the pendulum is heavy, I just can't think up another reason.

    victor
     
  26. KurtinSA

    KurtinSA Registered User
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    Victor -

    I get the same response over all of the teeth. The clock seems unmolested but it's been apart at least once. I found some scratching on the frontside of the front plate...someone put a date of 1981. But beyond that, things look OK...at least no one has attacked the peninsula eccentric. When I put the front and back plate together and aligned the holes, the anchor arbor holes are in direct alignment.

    I'm going to take it apart and recheck things. If I don't find anything, I'll just have to put it up on the shelf in baggies until I find a situation where I can figure out what is wrong with it.

    Kurt
     
  27. MartinM

    MartinM Registered User

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    Have you looked closely at the EW teeth and their alignment? Could be a bent tooth is stalling it in a way that won't allow it to gain momentum over the long haul.
    I like to use a block of modeling clay to check the teeth.
     
  28. KurtinSA

    KurtinSA Registered User
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    I did not inspect the EW closely...it seemed generally OK...I might still do that. In the meantime, I polished the pin and made sure there were no burrs on the inside of the fork. I also lowered the fork to 3mm below the guide. Been running for an hour, only 135 deg of rotation and maybe 20 deg of over swing. Sure doesn't seem worth it.

    Kurt
     
  29. tracerjack

    tracerjack Registered User
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    The mainspring is the last place to look, but it is a place. So, if everything else checks out - what's that Sherlock Holmes line, something like, if it isn't what it is, then it is what it isn't? I don't think that's exactly the line, but hopefully I have given you get the drift of it.
     
  30. sjaffe

    sjaffe Registered User

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    "when you have eliminated the impossible, whatever remains, however improbable, must be the truth"

    (Sherlock Holmes)
     
  31. tracerjack

    tracerjack Registered User
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    Yes! That's the line. Sounds so much better than the way I put it.
     
  32. KurtinSA

    KurtinSA Registered User
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    I'm finding that nothing is impossible with these clocks! Or many things are impossible. I'm so confused! :banghead:

    Kurt
     
  33. whatgoesaround

    whatgoesaround Registered User

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    Did you check the spacing of the fork? It is not just that a paper fits, but that it is that tight. Mainspring is a definite possibility and as long as it is apart, you might as well take it out and clean it. I have had to repeg holes more than once when I have had poor rotation. The fact that it is running seems to say that all is set up well, but as your title says, it is loosing power somewhere.
     
  34. KurtinSA

    KurtinSA Registered User
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    There is a paper thickness space between the fork and anchor pin. The mainspring was removed and cleaned during the clock overhaul. I can get the escape wheel to turn with just a few clicks on the mainspring...that suggests to me there is little friction all the way up to the escape wheel.

    I installed the motion works and restarted the clock last night. It ran for 2 hours and 45 minutes...stopped while trying to raise the minute hand past :45. So, not enough power and/or not enough over swing.

    Kurt
     
  35. MartinM

    MartinM Registered User

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    Did you say you'd tried putting the minute hand on the center arbor at 180 degrees from where it is, now?
    If it continues to stop at the same place, it's definitely a power issue. If it shifts to the other side of the dial, it's something in the center arbor, motion works or dial obstruction.
     
  36. KurtinSA

    KurtinSA Registered User
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    Martin -

    No, I didn't say or do that with this clock. I've decided to swap out main springs...got the clock pretty much torn down at this point. Will see what happens.

    Kurt
     
  37. KurtinSA

    KurtinSA Registered User
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    Probably kiss of death, but the spring change seems to have made a difference. It's only been a few hours, but the total rotation is up to about 220 deg and over swing is in the area of 40 degrees. I'll let things go over time and see if there's any improvement in that.

    The original spring is on the left, the replacement is on the right.

    Kurt

    Springs - Orig Left - New Right.jpg
     
  38. etmb61

    etmb61 Registered User
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    Not really a good analogy because you are describing a gravity pendulum. A better analogy in my opinion is rolling a loose wheel over a flat surface. It takes a lot of energy to get the wheel moving fast enough to keep rolling, but once moving it only takes a small extra input to keep it on it's way. The impulse from the 400 day escapement is given when the pendulum is moving fast, so the amount of energy can be very small. It just hast to come at the correct time.

    Eric
     
  39. Harry Hopkins

    Harry Hopkins Registered User
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    That's a big improvement and since all you did was change springs I guess we have to attribute it to the new spring although the old spring does not look like it was set. Did you measure the thickness of the old spring to see if it was the correct strength?
     
  40. KurtinSA

    KurtinSA Registered User
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    Harry -

    Yes I did. I got something a little over 0.016"...I've always had trouble measuring the spring thickness because of the curvature. I try and flatten it and then use my micrometer. To be honest, the replacement spring was a used one, but if my memory serves me right, I had a situation where I took a brand new spring (19x38) and swapped into a clock. In that instance, the swap didn't help me, so I concluded that the spring I took out was still OK. I wound that one up and put it back in my stash. This replacement spring also measure something over 0.016".

    So, it seems that the thickness was the same in both cases. I guess the "bad" was indeed set.

    Kurt
     
  41. KurtinSA

    KurtinSA Registered User
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    :banghead: Back at square 1. Clock ran overnight with good rotation/over swing as mentioned above. Then early this AM, I put on the motion works and hands. Clock stopped within 15 minutes at :45. Since the motion works went on in a random fashion, suggests that it's still a power issue. It could still be some interference with the motion works, so I guess I need to take it apart and investigate. I haven't been checking that lately since it hasn't cropped up that often. But I figured with that amount of over swing, I was going to be OK. Or not!!

    Kurt
     
  42. KurtinSA

    KurtinSA Registered User
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    Looks like it is the motion works. I just slipped on the intermediate wheel, hour pipe, and canon pinion without putting the hands on or even putting a pin in at the end...so all was just loose. Clock stopped at some point.

    Kurt
     
  43. MartinM

    MartinM Registered User

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    Sounds like you're sneaking up on it, alright.
     
  44. KurtinSA

    KurtinSA Registered User
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    Checked things out....I don't find nuthin' wrong with the motion works. :???: Not sure what to look at.

    So here's a dumb question. Remember that I'm likely not the first person to be inside this clock. So, when I took off the pin holding the minute hand on as well as the domed cover to the minute hand, I found a tension washer underneath with the concave side turned towards the dial. See picture. However, when I assembled the clock, I put the tension washer in the usual spot, concave side facing out, and put it first on the center arbor, then pinions, etc. Should I continue to have the washer in the standard location or go back to the way it came off the clock? Somehow, I think under the domed cover, it won't the right affect to create the tension needed to hold the minute hand.

    Kurt

    DialWasher.jpg
     
  45. tracerjack

    tracerjack Registered User
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    Putting it on the center arbor first is kind of the standard, so I think you were right to change its location. Have you tried moving the minute hand around full circle several times to see if you can feel a difference in tension or a catching point? I know I couldn't see any problem with the motion works on that Art Deco I was having trouble with, but I could feel the different tension. It also stalled at 15 or 10 to the hour. I don't know it if truly had any effect, but I removed the verge and let it all free spin to see if anything would happen to give me a clue. Something smoothed out, because after that, when I put the verge back, it worked and has been since. However, mine had the verge pivot in the bracket, so I didn't have to separate the plates. I don't know why, but I have had several clocks that were troublesome eventually become reliable performers after I just kept doggedly restarting them. My suspicion is that the gears and pivots have set in one position for so long, they need a certain amount of movement to get them working smoothly together again. Or, I may be completely wrong on that point, but for whatever reason, persistence has paid off for me several times now.
     
  46. KurtinSA

    KurtinSA Registered User
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    I will have some serious time in this one, that's for sure. I decided to put the tension washer back where it came off...I'll know in a bit of time whether that makes any difference.

    As a side note, I was thinking about something and smiling a bit. I recall when I took my first clock apart and I felt incredible that I even got it all back together, holding the plates while I snuck in with tweezers to move the arbors around to get the pivots in place, working from one side to the other. I remember that I "refused" to take it apart if anything needed attention, or if I thought I might have forgotten something. I just kept pressing forward. Nowadays, it not that out of the ordinary to take a movement apart 5-10 times or more in working through the refurb. It's a PITA but I know that's what needs to happen. Not quite like walking in my sleep, but I'm certainly more comfortable doing it.

    Kurt
     
  47. MartinM

    MartinM Registered User

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    It looks like you need to push the hour hand a bit further onto the pipe as it's hub is touching the minute hand's hub. Try it once without the hour hand and see what happens.
     
  48. KurtinSA

    KurtinSA Registered User
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    Martin -

    That was a picture of when I first took things apart. But I will certainly be sure when I get back to testing with the hands on again.

    Thanks...Kurt
     
  49. KurtinSA

    KurtinSA Registered User
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    What does it mean when the hour pipe "walks" forward on the cannon pinion, thus rubbing on the backside of the minute hand hub? As I think about it, I don't see why this couldn't happen on any clock. I've been running the clock in various stages, this time with no hour hand but the rest of the motion works...I have the minute hand pinned to the end of the center arbor. After running for a period of time, the hour pipe has begun to touch the minute hand.

    Kurt
     
  50. KurtinSA

    KurtinSA Registered User
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    I usually don't consider this, but I got the idea that I should look at wear in the plate holes. I unloaded all power and then used my finger to rock the mainspring barrel back and forth. The first wheel pivot clearly moves back and forth in the plate, and the second wheel does so too but much less. I guess that's not good, huh??

    Kurt
     

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