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Pendulum size does matter

timepast

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Aug 3, 2006
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I have a New Haven no 1 , 8 bell, labelled westminster but acutually whittington chime,1 gong clock circa 1895 that I have been trying to restore for the last 10 years. The case was missing all the top molding and other parts of the case, no dial, missing hands , no pendulum and VERY Dirty. I cleaned, oiled, and threw on a pendulum. It would tick a few minutes and then stop. Cleaned and oiled again , it then ran for 24hrs. Started the pendulum again and it would only run a 10 minutes and then stop. Could not find anything wrong . Every pivot, tooth and beat looked and sounded fine, the mainsprings still had lots of power . Totally expaspearated so put it away but every year I would work on it again for a week or two with multiple cleanings and sometimes it would run for day but mostly only a few minutes. Repeat this every year for 10 years and finally a member here 3 years ago suggested the typical pendulum for a New Haven was a 2.5-2.6 oz pendulum , Timesaver part xxx. After several more years of cleaning and oiling and more Exasperation, I finally ordered the suggested 2.5 oz pendulum . It`s now been running 48 hours!!! Amazing !!! I had been using a 4 or 5 oz pendulum . I didn`t think it mattered as I have had to guess on pendulum size and weight for other missing pendulums and never had a problem. And especially when the clock ran a couple of times with the larger and heavier pendulum a whole 24hrs. At least it`s running and now I can glue back all the hair I pulled outta my head in frustration..
 
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bruce linde

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ain't no expert, but i would say that pendulum weight CAN matter... but if everything is right, it really shouldn't.

out of curiosity... have you tried a hint of oil on the pallets? and locks and drops are spot on?

either way, glad it's running
 

ClipClock

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Looks like a nice movement, glad you got it working, (such perseverance! ) although I'm surprised the pendulum weight made the difference. Is it mid chime in the photo? Just wondering about the raised hammer
 

novicetimekeeper

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Jul 26, 2015
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you didn't say what weight you used before.

I originally read this sat in my sitting room just as my Richard Fennel did its occasional thing of banging the pendulum against the side of the case. In that case it is the bob diameter that is the problem. I keep meaning to modify it.
 

ClipClock

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you didn't say what weight you used before.

I originally read this sat in my sitting room just as my Richard Fennel did its occasional thing of banging the pendulum against the side of the case. In that case it is the bob diameter that is the problem. I keep meaning to modify it.
He said 4 or 5 oz :)

Did you change the rod as well? Just wondering if the old one was binding, or too sloppy, in the crutch loop. Such a small difference in weight!
 

Tinker Dwight

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Oct 11, 2010
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On a recoil, increasing the weight of the bob will increase the friction loss.
Recoils are more sensitive to running with the weight of the bob.
Since the recoil is pushing the pendulum for almost the entire cycle,
the rate is also significantly effected. A heavier bob will run slower.
A deadbeat is lesser effected by the weight of the bob. This is the design
intent of the deadbeat.
Still, the deadbeat becomes more sensitive to beat as the weight is
increased. The friction losses increase some but not as fast as they
do on a recoil.
Tinker Dwight
 

timepast

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Aug 3, 2006
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Broken hammer spring on the uplifted chime hammer but will deal with that latter. And the clock is still ticking.
 

timepast

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I Did not need to change the rod as this movement has a cuckoo clock like crutch with a small end hook to which I orginally attached to one of those generic american bobs which just has a hook .(looks like a timesaver 10213, 1 3/4``diameter, 5.2 oz) ; Replaced with a Timesaver 23584 1-1/2 `` diameter, steel rod 2-1/2 ``,2.5 oz. And it`s still ticking strongly after almost 5 days.
 

timepast

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Aug 3, 2006
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yes, I did put a hint of oil on the pallets. And the heavier weighted pendulum caused a much less amplitude for the pendulum swing.

- - - Updated - - -

The new and lighter pendulum has twice the pendulum swing amplitude. Thanks again to all your suggestions and help
 

tracerjack

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Was having trouble keeping a Seth Thomas T & S going. Read this post, changed the bob to a lighter one, and voila, as they say. I was also under the impression that weight didn't matter, but Tinker Dwight's explanation makes sense.
 

MartinM

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Jun 24, 2011
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As weight increases, the ability for the movement to impart an impulse decreases.
 

Berry Greene

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Oct 2, 2017
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I have a New Haven no 1 , 8 bell, labelled westminster but acutually whittington chime,1 gong clock circa 1895 that I have been trying to restore for the last 10 years. The case was missing all the top molding and other parts of the case, no dial, missing hands , no pendulum and VERY Dirty. I cleaned, oiled, and threw on a pendulum. It would tick a few minutes and then stop. Cleaned and oiled again , it then ran for 24hrs. Started the pendulum again and it would only run a 10 minutes and then stop. Could not find anything wrong . Every pivot, tooth and beat looked and sounded fine, the mainsprings still had lots of power . Totally expaspearated so put it away but every year I would work on it again for a week or two with multiple cleanings and sometimes it would run for day but mostly only a few minutes. Repeat this every year for 10 years and finally a member here 3 years ago suggested the typical pendulum for a New Haven was a 2.5-2.6 oz pendulum , Timesaver part xxx. After several more years of cleaning and oiling and more Exasperation, I finally ordered the suggested 2.5 oz pendulum . It`s now been running 48 hours!!! Amazing !!! I had been using a 4 or 5 oz pendulum . I didn`t think it mattered as I have had to guess on pendulum size and weight for other missing pendulums and never had a problem. And especially when the clock ran a couple of times with the larger and heavier pendulum a whole 24hrs. At least it`s running and now I can glue back all the hair I pulled outta my head in frustration..
Hey listen I have some hair you can have! Lucky to have any after the life I've led! That's a good account and I enjoyed your pain and your triumph. Well done!
I'm a collector who has had an interest in clocks & watches of the balance kind for a very long er - time. However until recently I had just the one pendulum striking job which I inherited from an aunt and which stopped running some years ago. . A C1890 French marble striker. Black Gothic looking with lovely clockwork that has stayed bright in the 30 years I've had it. It would stop the time train as it could not raise the rack and it jambed on the snail. I fixed that recently. It had a broken detent lever. Fortunately the pendulum needed no help from me. Keeps close time +/- 1min / week.between winds.
The confidence to tackle that came from a chiming clock I was given. It had been fitted with the wrong verge and would not run. With help from Simon Holt here on this forum I was able to make a new verge and get it running. A really nice clock by Smiths (K6A) some 63 plus years old, (1955/6).
I was then given a job lot of clock stuff which has kept me busy. Mostly movements without cases. I have rescued the balance stuff and moved on to the strike & chimers when there was a case to put them in equipped with the striking rods. Oh boy!
I have received superb help from the people of this Forum and it's given me confidence. I have now rescued 4 chimers but the fifth........ Hair anyone? Stripped and cleaned this triple choice chimer {it has Whittington, Westminster & St Michael options}, and it has come back well from the shaft surface rust and grime attracted during the years while hanging around waiting for me.
I now have the reverse of what you had. It works - but oh my only just - with a heavier (3.68oz) pendulum - maintaining (now 18hrs) whilst fully wound up with an arc of 3/8" (I make that 3.75 deg on this 6" pendulum), which means the beat must be exact or it will stop. Without the verge the train runs from a half wind of the mainspring and will re-start if stalled. I take that as reasonable evidence that stiction & friction is good and the mainspring is adequate - ah but is it? If I fit a lighter (2.35oz) pendulum,, it runs for as much as a minute and stops! I just don't get that. Oughtn't it to help? The escapement tics & tocs are so light until, that is, I manually help the minute hand a little bit, feeding in a little more power. Then she sounds more snappy.
I am now at a loss to know how to proceed. Any ideas would be welcome. The last of the cases is renovated awaiting. I am anxious to hear these various chime variations.
ATB BerryG
 

Berry Greene

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OK - thanks for the response. I do have some photos - so what I need to know right now is how to start a new thread. Leave it with me and I'll post in due course. Rgds BerryG
 

R. Croswell

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OK - thanks for the response. I do have some photos - so what I need to know right now is how to start a new thread. Leave it with me and I'll post in due course. Rgds BerryG
Go here; Clock Repair and click on the green box in the upper right part of the screen. Before clicking the green box, look a bit further down in the "sticky threads" and read the piece about how to attach pictures.

RC