Oil or Don’t Oil?

Discussion in 'Electric Horology' started by Pete Riegel, Nov 12, 2006.

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  1. Pete Riegel

    Pete Riegel Registered User
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    Oil or Don’t Oil?

    A variation of this post appears in the “Clocks” section of the Message Board.

    Should this movement be oiled? If so, how is it done without making a huge mess? The movement is teeny.

    Last week I bought this clock. I’ve always admired the concept of the pendulum-driven movement, as it runs with much less gear and bearing contact force. Plus, I like to watch it work.

    130.jpg

    The main vertical support plate has this on the front:
    Junghans
    ATO

    On the back is a serial number:
    518959

    The movement is marked on the front:
    Henry Coehler Co. Inc.
    No (0) Jewels

    Also:
    Unadjusted
    Made in Germany

    The clock is driven by:
    Horolovar Long Life Battery
    Size 8 or 9

    From what I’ve found out so far I have decided not to oil this clock. I would only make a mess of it and I do not believe the mechanism requires it, as the operating forces are very small.

    Also, can anyone tell me what I’ve got?
     
  2. eskmill

    eskmill Registered User
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    For certain, Pete, the movement was lubricated when new but we don't know what Coehler used for oil. Whatever it was, it will have changed its character over the years.

    Disassemble the movement, peg the holes and look at the pivots with a 10X glass for any evidence of roughness. Then reassemble and oil each pivot and friction point using the same techniques as with a pocket watch. Leave the hands motion works and the drive pawl dry.

    The ATO designed clock is extremely efficient as are all "weak-current" battery clocks but that does not mean they never had or don't need some lubrication and perodic cleaning depending on environment.
     
  3. DC Kelley

    DC Kelley Registered User

    Mar 16, 2006
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    I love this movement, and have been rather greedily collecting them lately. It looks like you scored one from late 1950s just before the transistor replaces the small contact switch at the right side. If you chose to oil it, remove the clock from the back frame (two screws) and it is much easier to get at the back side.

    I have the same question about the proper care of the movement. This one has 4 jewels, most of the early Kundo ones have 6 and a few of the ATOs ones have 7. In all the cases I have looked at (several dozen now) the pivots are very clean and I have yet to have any reason to play with the jewels or even burnish the things. I presume I should treat it more like a watch (including a very light grade of oil) then like a clock? I have been holding off oiling mine until I learned more, presuming I could always do it later. I am tempted to only oil the jewel points. Les, what do you advise?
     
  4. eskmill

    eskmill Registered User
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    Admittedly, I have been tempted to leave these little movements just as found when they look like they've been kept covered and protected from dust.

    On the other hand, we have one or two that when obtained looked super-squeaky clean but balked often and just wouldn't perform. Upon disassembly and inspection, the cleanliness was only superficial, the holes and pivots were gummy on on one that I recall. Another one, I could see some corrosion on the arbors, obviously it had been subjected to a moist environment despite the glass dome. I was suspicious on account of the condition of the brass base.

    We have one or two that I didn't take apart and the last time I looked at that shelf, they were all running OK.

    I suppose that you might get away with never lubricating them ever. They will run well past the shelf life of the dry cell if in decent shape. However, I honestly believe that the next owner will have a good runner if it has been kept clean and lubricated.
     
  5. Pete Riegel

    Pete Riegel Registered User
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    The clock is running well with no apparent problems. Examination of the assembled movement with an 18x loupe reveals no sign of dried-up goo. The contacts show minor erosion, but nothing serious, and which, if it should become a problem, can be fixed with a minor repositioning of the contacts. No eccentricity is detected in any of the bushings.

    Whether the thing was prelubricated at the factory I don't know. I saw no sign of any lubrication ever being present.

    I know that sooner or later I will disassemble the movement simply because I enjoy the process. For now I just want to watch it and gradually learn what I can.

    I've never contemplated collecting or disassembling watches, and am unfamiliar with the techniques. This movement is very watchlike in size, with tiny pivots, some the diameter of a common sewing pin - less than a millimeter. It will take a lot more care in the disassembly/assembly process than do the clocks I have fiddled with. First, do no harm.

    Whether this relates to the prohibited "value" postings, or not, I can't say, but I paid $85 for it and felt I'd got a bargain. It was irresistible. I came to the mart just to look, as I was certain I had enough clocks to suit me, but I couldn't pass this one up.

    I am looking forward to the battery dying, as it will give me something to do.
     
  6. DC Kelley

    DC Kelley Registered User

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    I think we are allowed to speak of value in general market terms. In that context, the more common Kundo's are going on the ebay market from 40 to 100 although more unusual casement seem to easily double this.

    The price you paid seems average and fair to me. The ATOs (which are less common then the Kundos) seem to fetch about 30~50 bucks more. The early mechanical switch types seem worth more in the market then the transistor one. Most of the ATOs/Jun were these square box style, but an oval glass dome also exists (my own favorite)

    Here is the latest representative recent "high water" case for ATO, the more typical price seems to be 1/3 of this.http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=016&ss...0050740718&rd=1&rd=1
    This example seems to pre-date the one piece oval dome with some sort of prototype dome I had not seen before.

    Enjoy your new toy. Timesaver and the other normal sources of supply has a nice metal box battery converter when the time comes. But, the terminal on that one are a bit too bit to actually fit the Kundo metal tabs. Many people seem to like a simple one dollar plastic battery holder from radio-shack etc and some double sided tapes.
     
  7. DC Kelley

    DC Kelley Registered User

    Mar 16, 2006
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    So I wish to ask again, what type (i.e. brand name) of oil does one use for a small clock that is more like a watch movement?

    Regarding the friction of the moment, here an easy test. With the battery removed and the unit level, hold the pendulum at one extreme and release. You should see at least 30 swings before the pawl ceases to engage the wheel and advance the train. Fifty to Sixty would not be unusual. The actual drive power is less then 10 microwatts, so any friction to speak of will kill the swing, which otherwise should be quite strong. Less friction, however, will not extend the battery life, or (if you presume it is constant) improve the time keeping.

    In the spirt of scientific inquiry, I will disassemble a couple of these (one with jewels, one without), dunk in the cleaner. peg everything out well,and reassemble them - then test the swing count before and after some oil.
     
  8. Pete Riegel

    Pete Riegel Registered User
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    Interesting experiment - I eagerly await results.

    If the oiled train produces less friction, does it then follow that the movement should be oiled? Should ALL pivots be oiled? There is one pivot that is also an electrical contact, the one on the cam that transfers motion from the escape wheel to the contact switch. Oil could affect the electrical flow here.

    So far no one has addressed the question of neatness in oiling. One small mistake and oil gets on the plate, messing things up. Also, the question of oiling the bushing behind the central exterior gears (hour hand drive) has not been addressed.

    It is beyond my powers to oil a movement like this and maintain a picture-perfect set of plates. Fortunately I don't think it is necessary.
     
  9. Pete Riegel

    Pete Riegel Registered User
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    Just for fun, with the clock running normally, I flexed the contact points a bit, to remove electric power, and counted impulses after the flex. I found that the clock continued to operate the escapement for 22 to 26 swings, then ran out of gas. Since I intend to do no oiling I will not have a comparison to offer, but I offer this for what it's worth.

    I suspect that the amount of swing will be affected by adjusting the clearance in the contact points, thus varying the duration of coil activation, but plan no experiment.
     
  10. Ralph

    Ralph Registered User
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    As I said in the other thread, you should oil the pivots, except the index pawl pivots. If there is a pivot in the circuit, I would not oil that either.

    Quality oiling should not be a problem. If you can't do it, you can always find someone who can. If you take it on and get sloppy, take it apart clean it and start over.

    This is a simple movement, easily removed, disassembled , oiled and replaced...

    The center arbor pivot wuold be exposed and would be oiled during reassembly.

    Will it run not oiled? Yes.
    Will it wear more without oil? Yes.

    DC offered a good test to prove/disprove the benefit of oil.

    Ralph
     
  11. DC Kelley

    DC Kelley Registered User

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    I am afraid my planned clock play time has been cut short today by a nail in one of my tires, but regarding HOW you would oil the movement, any needle drip application to the pivots and/or jewel holes should be fine. Still not sure what oil is in fact best to use, but my favorite synthetic blend (Dr Tillwich, Werner-Stehr Type 3-5) is what I will use here.

    One issue to bring up on your ATO if you oil is that one of the pivots is not jeweled but covered by a thin metal (almost foil) cap that you will want to carefully pull aside before oiling. Here is a close up where you can see the cap http://www.itsware.net/blindlinks/clks/drivecir/atoswitch.jpg I am not really sure why this was built this way. Hidden from this view, on the backside there is a small hairspring, be careful near that. When the relay contact plate was removed in latter designs, this pivot got 2 simple jewels, as in this Kundo of the same period http://www.itsware.net/blindlinks/clks/drivecir/kdswitch.jpg

    By index pawl pivot I presume Ralph means that very short thin wire hinge point on the pendulum which it rotates during the return swing to allow the pawl to slide over the rachet gear. Prudently oil all the pivot holes you find on the round frame area with a tiny drop and call it a day.
     
  12. Ralph

    Ralph Registered User
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    DC,

    What I am calling the pawl is the steel piece that drives the index wheel(escape wheel). I have trouble calling it an escape wheel. I would not oil the pivots on it. I might put a film on the pawl driving face.

    The jeweled holes would be oiled very sparingly. In fact I might consider oiling the pivot while assembling and remove any excess, leaving only a film, before inserting in the jewel hole.

    I like some oil present, if for no other reason , to prevent oxidation.

    Ralph
     
  13. DC Kelley

    DC Kelley Registered User

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    Ralph we are on the same page. Frankly I am afraid to touch that part, I have no tool small enough to drive the pin out. I have had to re-surface the face slightly a couple time, but that is it.

    I working on my outline for these tests, and should be able to do the first set of tests Saturday (existing clocks untouched with and without oil). The second set (same clocks after a total train disassembly) will take a bit more time and stretch my skills because there are some hairsprings used here. I plan to do a set of six clocks, two mechanically switched, three jeweled, one with no jewels- all with the same Leon Hatot movement.

    But as I am building up the text to describe this movement, I want call the wheel the pawl interfaces with the "1st Wheel" which (in my novice experience) is the reverse of the norm, but that seems more correct from the perspective that this is where the drive power enters the train. Is there any sort of acceptable convention for numbering the wheels in reverse when they are in fact driven that way (as in this clock)? Need to learn before I commit a faux pas here.
     
  14. eskmill

    eskmill Registered User
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    DC Kelley writes in part: (quote) I want call the wheel the pawl interfaces with the "1st Wheel" which (in my novice experience) is the reverse of the norm, but that seems more correct from the perspective that this is where the drive power enters the train.(unquote)

    'Really a good question Kelley; and to reply leads to the minefield of semantics.

    There is no escapement device in these magnetically impulsed timepieces. There is no escape wheel and there is no verge and no palets. The single commonality is the "motion works," the wheelwork that manages the hands or pointers in a 12:1 ratio.

    All the wheel work in these clocks is simply an motion counter counting pendulum strokes. Thus much of the horologist's vernacular doesn't apply.

    How you identify the pieces of the counter is unimportant. Just don't call the ratchet wheel an escape wheel....it ain't. ;)
     
  15. John Hubby

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    I agree with Les regarding the "escape" wheel, which is really nothing more than a beat counter. Same thing applies to Bulle clocks and many others that use a pendulum impulse to simply move the motion works one tooth forward.

    Re oiling, I always oil these clocks after cleaning except for the pivots that participate in making the circuit (if any). I use Etsyntha 5 light synthetic clock oil in a micro-drop syringe and have never had a problem with the clocks stopping between battery changes. Keeping the dome in place and starting clean, they don't get dirty at all over time and by using synthetic oil there is no gumming up.

    Finally, re the funny looking dome that was on the eBay clock, I've seen four or five of those. I think they may have been early production prior to the introduction of the oval glass dome.

    John Hubby
     
  16. DC Kelley

    DC Kelley Registered User

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    I spent the day running testing on the several clocks, and will publish a fuller report on the details by Monday, complete with some closes up of the pivots and jewels. But I am a bit disturbed to report that while the addition of oil seemed to produce an increase in swing count (and hence an overall loss in the fractional drag) it was only ~6 percent in the five clocks I was able to test (in fact I tested a 6th but dropped the movement on the bench and broke a pivot I now need to fix). Frankly I was expecting something a bit more dramatic. Of the six, two showed no change, the others improved. Ironically, the movement I felt was the most filthy was one that showed no change. Now I want to see what a cleaned movement will do (with and without oil), but 6 movements will take me some time.

    And I used an Etsyntha 3~5 for the oil on this. I oiled the pivots of the switch, as pushing that part is the major "work" friction done by the pendulum. But not of course the small pin/pipe that in fact lifts the relay wire (both of the mechanical ones use a common frame ground return) It a bit of a pain on the mechanical ones as there is a hair spring used to assist the gravity return design in your way on the back plate.
     
  17. DC Kelley

    DC Kelley Registered User

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    Here is my more detailed report of the tests with and with-out oil in the works.

    http://www.itsware.net/blindlinks/clks/oilfriction.htm

    Feedback and corrections are very much sought. I will be cleaning the clocks involved here for the 2nd half of the testing over the next week.
     
  18. eskmill

    eskmill Registered User
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    Kelley's report is, without question, the most carefully conducted experiment ever reported here. Still incomplete, it's commendable.

    I (and others) anxiously await the conclusion.
     
  19. Pete Riegel

    Pete Riegel Registered User
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    Kelley –

    Very nice report. With luck we will see a difference – oil vs no oil. I believe we will see operational differences but will learn little about overall longevity of the clocks.

    It is obvious that a lubricated clock will wear slower than one which is not lubricated. I don’t think it is obvious whether the clock will operate better over the long haul with lubrication. A clock which is spring- or weight-driven has far more force exerted on the gearing and bearings than does a pendulum-driven clock, which has only the weight of the hands to resist motion. This friction leads to resistance to movement, balky operation, and wear.

    The manufacturer of a spring- or weight-driven clock would be well-advised to lubricate the clock at the factory. It will last longer and run better before it comes to a halt, as most clocks purchased sooner or later do. Most clocks are bought by people who are not clock-obsessed, as we are. The purchaser will, at that point, either abandon the clock to its halted state or take it to a clock repair person for a fix. If enough time has gone by since the clock’s purchase, the customer will not feel cheated – after all, everybody knows that things wear out sooner or later, and need fixing.

    The manufacturer of a pendulum-driven clock will consider the probable life of the clock before its first fix. If initially unlubricated the clock may run for decades without significant wear. This will make for a happy customer. If lubricated, the lubricant will, in time, dry out and perhaps become sticky or gritty. Whether lubrication will produce a longer time before fixing is needed is unknown to me, but it is something that the manufacturer may consider. Their object is to have the clock run properly and well for the longest time after purchase. If wear is the price to be paid, it could be they are willing to pay it. In the customer’s eye, a long-running clock is better than one which requires frequent trips to the repair shop.

    Also to be considered is the skill of the maintenance/repair person. The movements we have in pendulum-driven clocks are watch-like and delicate. Over time, if periodic disassembly, cleaning, reassembly and lubrication is performed, how long will it take before someone inadvertently breaks or maladjusts something? This periodic activity will also have an effect on the life of the clock.

    Where does this leave us as owners? What the manufacturer intended is less important to us than what we intend for our clocks. After all, we are the owners. If the manufacturer did not initially lubricate the clock does this mean we should follow suit? If we lubricate we commit ourselves to a periodic cleaning and relubrication. If we do not, we wait for the clock to inevitably grind its way to oblivion. Either way the clock is going to wear out. The only difference is time.

    In my case I am content to leave the clock as-is.
     
  20. Ralph

    Ralph Registered User
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    Bob,

    I don't see how you can conclude that a pendulum clock will run for decades without lubrication. I would suggest it won't run a month.....unless way over powered.

    On DC's test, I would have liked to have seen minimum lubrication on the jeweled holes. In fact, as I earlier proposed, I might only put a film on the pivots and then assemble.

    7% improvement would solve much of our country's energy problems.... for a while anyway.....

    BTW, DC, nice job on the study.

    Ralph
     
  21. Pete Riegel

    Pete Riegel Registered User
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    Ralph,

    Read the post (by me, not Bob, whoever he is) more closely. It refers to a pendulum-driven clock, not a typical spring- or weight-driven clock. Pendulum-driven clocks have virtually no load on the gear train, thus have very low friction, and wear very little. They run for a long, long time with little maintenance.
     
  22. Ralph

    Ralph Registered User
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    Pete,

    I guess we can agree to disagree. If it goes around, with metal to metal contact, I say lube it. It does not have to be flooded.

    With jeweling, like I said in another post, I might opt to put a film of oil on the pivot.

    Instead of saying they run a long time with little maintenance... I would instead say they last a long time, because people quit running them.... lack of batteries, broken suspensions, taste changes, lack of setup knowledge, etc.

    I'll be interested in seeing DC's followup with the dry movement and the clean movement.

    My wondering is the movements with little improvement may have already had residual lubrication in their precleaned state. So with additional lubrication, little improvement would be realized.

    Ralph
     
  23. Pete Riegel

    Pete Riegel Registered User
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    I suspect that the movement parts probably carried a film of lubricant left over from the various machining operations, unless the makers degreased them before assembly, which seems possible but unlikely.

    Whether they added more - who knows?
     
  24. DC Kelley

    DC Kelley Registered User

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    #24 DC Kelley, Nov 23, 2006
    Last edited by a moderator: Dec 7, 2017
    Lets do as Ralph suggests once I clean the movements and then do it again. I purposefully over-oiled in the first set of tests, thinking it might flush things a bit. In microscopic examination (about 40~90x) I saw no signs of any prior oil films. But I did see some pitting, presumable from prior oil reaction-erosion. Need to see more of the pivot to be sure. Also, I am very curious in this clock to see what the inner side of the jewel looks like against the shoulder of the pivot. Depending on the inner shape of the jewel, and the capillary action of the oil, this may be the biggest point of rolling friction.

    A thought that occurs after I posted. Keep in mind that ANY addition of oil also adds a component of new friction by it very presence. You must overcome the viscosity of the oil to move through it (which presumably is then less then the metal on metal sliding friction) In a light load train like this one, this is mostly a shearing film. I presume that in the ideal world you want the capillary gap the oil was designed for between the pivot and the jewel, but NOT between the side of the pivot and the shoulder. But if you undercut the jewel, you are going the have a more concentrated edge of the shoulder digging into it on which ever side of the plates it tends to. Over time that would grind. Perhaps we could test this with type-3 versus type -5 oils. Type-5 (as a thicker oil) would have more shearing drag and may be more likely to wick onto the shoulder. I will keep a sharp eye on the inner jewel surface when I disassemble these clocks next week.
     
  25. eskmill

    eskmill Registered User
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    When you disassemble one or more of the jeweled movements, look closely at the jewel hole shape.

    Some of the better watch jewels are "olived" so-to-speak for lower friction. Thus the bore is relatively shallow compared to a straight bore.

    The same concept is seen in some very old Black Forest clocks which with their thick wood plates and very long brass bushings. The makers shaped the arbor pivots with a "barrel" shape for lower friction.
     
  26. Pete Riegel

    Pete Riegel Registered User
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    The typical clock bearing, usually a cylindrical steel shaft running in a brass cylinder is known technically as a “journal bearing.” A properly designed and well-lubricated journal bearing will run practically forever without wear. A description of the way it works is found in Design of Machine Elements by V. M. Faires, MacMillan, New York, third printing, 1955. It is shown below in bold.

    131.jpg

    “Mechanism of Lubrication. Let a journal be at rest in its bearing, as shown diagrammatically in Fig. 208 (a). The clearance space is filled with oil, and the journal rests on the bearing in metal-to-metal contact at the lowest point. As the journal with the load (or bearing reaction) R begins to rotate clockwise, there is first some rubbing of metal on metal, and the journal climbs upward toward the right on the bearing, Fig. 208 (b). However, since oil adheres to the surface of the journal, the rotation draws in an oil film separating the journal and the bearing, at which time the journal moves to the left and assumes a position eccentric to the bearing, as in Fig. 208 (c). The rotating journal, acting as a pump, causes enough pressure to be built up in the load-carrying area of the oil film to bring about a complete separation of journal and bearing….”

    The above describes a bearing which, once started, continues to rotate, and exists in a condition of continuous lubrication. In the case of the clock, however, almost as soon as movement starts, it stops again, and the journal never reaches a condition where it continuously rotates and is hydrodynamically supported. So, at each tick, we see the bearings making metal-to-metal contact.

    Metal-to-metal contact may possibly be overcome by the use of very heavy, thick grease – but this resists rotation, and causes friction of its own, affecting clock accuracy. Still, if metal-to-metal contact is avoided, wear will not occur.

    Use of a very thin lubricant will not support the journal when it stops, some metal-to-metal contact will occur, and some wear will occur at each tick.

    All of the above leaves me more than a bit confused. The classic journal bearing description does not seem to fit the kind of bearings we have in the typical clock. It seems plausible that oil will do some lubrication, but will not entirely eliminate metal-to-metal contact.

    In the case of the ATO clock, some of the bearings are tiny and, in the case of the pawl bearing, not readily disassembled. The bearing, once lubricated, cannot be periodically cleaned. If the lubricant turns to gunk, it stays where it is.

    All this theoretical stuff is irrelevant to my individual case. What I have is a clock that is so watchlike that I am a bit afraid to take it apart completely. The presence of the hairspring, and how to deal properly with it, is also a complication. With my other clocks, I periodically take them completely apart without fear, clean them, lubricate them, and put them back together. With this ATO I think that periodic disassembly by me will sooner or later lead to maladjustment or even breakage. This would really shorten the life of the clock, and much more quickly than bearing wear. And I dislike the idea of a repair person of unknown capability taking on the solution of what is, for now, a non-problem.

    Sooner or later I may attempt something, but for now it doesn’t seem like a good idea to fiddle with it. No apparent wear is visible, and the thing is running like a champion.
     
  27. Ralph

    Ralph Registered User
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    "The same concept is seen in some very old Black Forest clocks which with their thick wood plates and very long brass bushings. The makers shaped the arbor pivots with a "barrel" shape for lower friction."

    Les, I always thought that was to accommodate the misalignment of the plates, due to the way they are constructed and hung .

    Cheers, Ralph
     
  28. DC Kelley

    DC Kelley Registered User

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    Pete, leave your clock alone and don't oil it until you feel the need. Given it has worked well for 50 years, I don't see the need to hurry. I love where your post has lead to in this thread. I confess I too am nervous about touching the hair spring (am taking the TZ watch school web course as a precursor)

    I think your point about the pivot shaft stopping in a clock is the key to understanding things. The shearing force of the oil is balanced by the pressure wave of the edge rolling, and the point of balance helps determine how eccentric the dynamic point of rotation is. But when things stop, the pressure dissipates, gravity takes over, and the main forces are the surface tension of the oil and its "sticky ness" (sorry do not know the technical term for adhesion). I think these still contributes to a working film between the bottom of the pivot and the jewel, so abrasive contact is minimal. I think the issue comes down to what sort of static pressure the oil film can support.
     
  29. Jim Duncan

    Jim Duncan Registered User
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    Was wondering if this thread was ever concluded or continued in another? The links to data are dead, so if anyone (Kelley, Hubby, etc) can provide a new link it would be great for those of us are still wondering if we should oil our ATO.

    Jim
     
  30. eskmill

    eskmill Registered User
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    Jim and all: While this thread is "ancient history," I think the interchange is still valid. However, the relatively few "available" Junghans ATO dry contact battery pendulum clocks is by now much fewer, most of the information interchange concerns more about just getting one to run reliably and keep a decent rate.

    I think there were some very valid arguments seven years ago on the subject of lubrication of the tiny movement. Some have their pivots running in hard jewel holes while others have soft brass holes and that a non-perishing kind of lubricant is essential to inhibit corrosion of the steel pivots more than reducing friction.

    I think Pete Riegel is still around. DC Kelly seems to have disappeared and I, at 82 years of age, I suffer from being impatient with queries that tend to indicate or suggest that the requester hasn't tried self-help and wants to be "spoon-fed." Of course, John Hubby is the principal administrator of the Message Board.

    Lubricate the movement with a very high quality thin synthetic watch oil. (if there is such an oil)
     
  31. Jim Duncan

    Jim Duncan Registered User
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    May 31, 2011
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    Hi Les - Thanks for the words of wisdom. I'd always heard "older and wiser" but now that I'm one without the other I have my doubts. I'm working on an early 1/4 beat ATO so just have to deal with soft brass holes which have sinks, some on the shoulder side, so I lean towards the lubricant side. The parts are soaking in cleaning solution as I type this.

    Your comment regarding requesters seeking to be "spoon fed" caused a pang of guilt to arise when I read it. I joined the clock hobby a bit late in life (my sixties) and don't know that I'll ever get to the "experienced" stage. And I live out in the boonies so can't toddle on down to a fellow horologist and talk it over. Thus the internet has become a huge benefactor of knowledge, experience, and conjecture - especially this forum. And it is interesting (and at times frustrating) when experienced members have differing opinions.

    On this ATO: before I bought it I read up as much as I could find online. Even looked up the US Patent and had a read. And I signed out the John Locke book on them from the NAWCC library. But it was a slim book and mostly about the Junghans versions. Still it was good to learn what I could. The forum and its archives have been the biggest help, especially when wise "old timers" like yourself take the time to share your knowledge and experience.

    Jim

    PS: I am thinking of using Etsyntha 859 as the oil, and will definitely not include the contact points.
     
  32. coldwar

    coldwar Registered User

    May 20, 2009
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    Why not refer to the factory notes, 1951:

    89.jpg



    FWIW I never saw the need to oil these, much like ATMOS. But, never saw one with any rust either. Junghans mentions the availability of 'steam proof' case examples in the notes. I might oil one with escapement oil and observe. CW
     
  33. Jim Duncan

    Jim Duncan Registered User
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    CW - Excellent reference! Do you have the diagram with numbered components that are mentioned at the bottom? I'm not sure what the lifting roll is.

    Jim
     
  34. eskmill

    eskmill Registered User
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    Jim. you need to realize that the instructions Coldwar kindly provided were written by a German language speaking person who carefully translated the instructions into English, French, Spanish and many different languages from his native German language.

    The lifting roll (or roller) is located under the Switchwheel. (ratchet) The lifting roller acutates the lever that closes the electrical contacts.
     

    Attached Files:

  35. Jim Duncan

    Jim Duncan Registered User
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    Ah, this isn't part of the early ATO designs, at least not on the 1/4 beat version. Thanks for the picture Les.

    Jim
     

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