Euramca timing problem

Discussion in '400-Day & Atmos' started by Harry Hopkins, Dec 11, 2016.

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  1. Harry Hopkins

    Harry Hopkins Registered User
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    #1 Harry Hopkins, Dec 11, 2016
    Last edited: Dec 11, 2016
    I recently finished a complete overhaul of a Euramca 400 day clock. It is plate 1088 and the pendulum is #61. The book calls for a .0023 spring. After making up the new suspension assembly and ensuring the clock was running strong I started regulating it. I could not get it in range with the .0023 and ended up with a .0025 spring and had to slightly thin it and now I was getting very close to 8 BPM. I set the time and walked away for about an hour. When I came back the clock was about 4 or 5 minutes fast so I checked the BPM again and it was still very, very close to 8 so I reset the time thinking I had maybe set it wrong the first time. As it turns out the clock was consistently running about 5 minutes an hour fast with what seems to be the correct BPM. I had watched the escapement for several minutes and never saw any flutter but I raised the fork slightly anyway with no change. The minute hand is tight enough I am sure there is no slippage. I decided to set the minute hand to 12 then manually operate the anchor pin with my finger for 120 beats and the minute hand moved slightly more than 16 minutes (120 beats should equal exactly 15 minutes). I did this test several times with the exact same result each time. There are no missing teeth on the escape wheel. I have no history of this clock before I tore it down but it was in fair condition when I got it.. The only missing part was the lower suspension block. All the wheels and pinions were in good condition and nothing has been obviously replaced. The only other new part is a new mainspring that I put in. The pendulum motion is excellent as I am getting about 540 degrees rotation. So... before I tear it down again to count teeth and pinion leafs to see if it adds up to 8 BPM does anyone have any other suggestions? I am sure I could simply change the suspension spring again and I could bring it to correct time but that is not really the best solution.
     
  2. leeinv66

    leeinv66 Moderator
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    #2 leeinv66, Dec 12, 2016
    Last edited: Dec 12, 2016
    Ah, you have one of those ;) This thread might clear things up for you. These ones are not 8BPM. Click Here
     
  3. Harry Hopkins

    Harry Hopkins Registered User
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    Thank you Peter, Very interesting reading for me. I have worked on many 400 day clocks and have never had one of these cross my bench. Simple now to change suspension spring again and time for 8 beats in 64 seconds instead of 60. Also.. when I was replacing the mainspring I thought to myself "That is a lot of spring for this little clock" I guess that is why I have the 550 degree rotation and about 90 degrees of overswing.
     
  4. shutterbug

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    WOW! That is a great little runner there!
     
  5. KurtinSA

    KurtinSA Registered User
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    I have one of these up and running. Didn't know about the 7.5 BPM...I've updated my guide. Also, I noticed that the adjuster nut is backwards relative to just about all others I've seen. No "+/-" or "F/S" on the top of the nut, although someone tried to write something in pencil. Took me a while to realize the change.

    Kurt
     
  6. shutterbug

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    I have a note on the other one (1087) too. With the .0023 suspension, I was getting 9.56 BPM, and the recommended suspension units were not accurate. It needed 10.9mm according to my notes. I wonder if I maybe miss ID'd it?
     
  7. Harry Hopkins

    Harry Hopkins Registered User
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    #7 Harry Hopkins, Dec 13, 2016
    Last edited: Dec 13, 2016
    I suspect both the 1087 and 1088 plates use the same suspension and that both are incorrect in the RG. I ended up using a .0025 spring but had to thin it slightly. When I put it in I was still thinking that I wanted 15 second beats instead of the 16 second beats this clock requires so I might have gotten by with .0024. Regardless.. I have marked both plates in my guide so to at least be warned the next time.

    Kurt, mine has a pendulum locking guide above the adjuster nut and it is marked F & S and it is CW to make the clock run faster which as you say is backwards to most. I am guessing that yours is plate 1087 as that plate does not show the threaded holes on the bottom of the plate for the installation of the pendulum locking guide.
     
  8. KurtinSA

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    Harry -

    As it turns out, my plate is 1088 and I don't have the locking guide...the two screws are there, but no guide. I also noticed that the pendulum feature, which consists of a bar turned left or right at the back of the base, doesn't really work. I haven't investigated why it doesn't work. I'm just glad that the clock is working. Thanks for confirming the backwards nature of the adjuster.

    Kurt
     

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