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Old 31st Mar 2017, 12:10 pm   #1
StephenC
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Default Metamec mains electric clocks - second hand erratic

I wonder if any electric clock experts out there can kindly offer a little advice. I have three Metamec mains electric clocks, all used to work but all are now exhibiting very similar faults, so I suspect this relates to the same problem. In all cases the second hand started to run erratically. By this, I mean that the second hand seems to be "struggling". Instead of sweeping round at the same rate, for a few seconds it runs visibly slower (seems to be wading through treacle) then it recovers itself and sweeps noticeably faster, then slows down again. The best one I have seems to cycle through this about every 5 seconds! Due to the regular nature of the slowing down and speeding up, it would seem (in my layman's view) to be perhaps related to wheel(s) inside the clock which at a certain point in their rotation are not as free as they should be. Now to the tricly part - I am sure you may advise "take the clock to pieces and clean it". However my sight and fingers are not what they used to be, and I'm afraid that it will never go back together again if I disassemble! Could it possibly be a simple case of just oiling a pivot? I am a complete clock novice by the way! All advice gratefully received!!
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Old 31st Mar 2017, 12:45 pm   #2
Nickthedentist
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Default Re: Metamec mains electric clocks - second hand erratic

Hi Stephen and welcome.

I'm not a Metamec expert but I have some scrap movements here to look at.

Could you post a picture of the movements fitted to your Metamecs, please?

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Old 31st Mar 2017, 4:31 pm   #3
emeritus
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Default Re: Metamec mains electric clocks - second hand erratic

I had a 1940's model in the late 1960's that would sometimes go backwards for a few seconds before resuming normal rotation. I was a student at the time and never did bother to find out what caused it, as I found out that it worked normally when laid on its back. I only needed it to get me up in the morning so the horizontal face wasn't a problem. I now suspect that it might have been hardened grease in the motor pinion, as that was the cause of erratic behavior in the clock of my mum's Teasmade. I had to pick the grease out from between the teeth with a sharp sewing needle
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Old 31st Mar 2017, 6:13 pm   #4
mark_in_manc
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Default Re: Metamec mains electric clocks - second hand erratic

Here are two threads where folks (including me) have tackled what might - or might not - be the same problem with a Metamec synchronous clock movement.

https://www.vintage-radio.net/forum/...d.php?t=125485

https://www.vintage-radio.net/forum/...d.php?t=111353

Maybe you can have a read over these and then have a look at your three movements in the light of what is there. If it turns out to be the same problem that I and one or two others had, it's not impossible to fix with a little patience.

Good luck

Mark
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Old 31st Mar 2017, 6:17 pm   #5
The Philpott
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Default Re: Metamec mains electric clocks - second hand erratic

My father has one of the 1960's Metamecs, i will quiz him over the weekend to see if he's ever had it apart.

I would say this is definitely a dismantle job- any lubrication or cleaning attempted from outside is unlikely to get to the correct places.
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Old 31st Mar 2017, 10:41 pm   #6
Phil G4SPZ
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Default Re: Metamec mains electric clocks - second hand erratic

Quote:
Originally Posted by emeritus View Post
I had a 1940's model in the late 1960's that would sometimes go backwards for a few seconds before resuming normal rotation. I was a student at the time and never did bother to find out what caused it...
Some types of self-starting synchronous clock motor will start and run in either direction. I once owned a 1950s clock that exhibited this behaviour, and on investigation I found that the gear train incorporated a special cam which was designed to stop the train if the motor started in reverse, and jerk it into rotating the right way! Crude but effective.
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Old 4th Apr 2017, 12:32 pm   #7
trsomian
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Default Re: Metamec mains electric clocks - second hand erratic

Most self starting synchronous motors will start equally well in either direction, so they then have a mechanism of some sort to restart them the correct way if they get it wrong the first time. With some microwave oven turntables they don't bother, so sometimes the turntable will go one way, other times the other
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Old 4th Apr 2017, 2:06 pm   #8
paulsherwin
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Default Re: Metamec mains electric clocks - second hand erratic

If you run the clock with the movement removed from the case then it should be obvious what's happening. I would imagine one of the wheels isn't meshing properly, possibly the one that takes the drive off the motor. Dirty or dry bearings will make this worse by increasing the torque required.

If you don't feel up to dismantling the movement and cleaning everything properly, you could just apply a single drop of machine oil to each wheel bearing, and clean the wheels themselves as best you can with a soft rag. Don't oil the wheels themselves.

Don't be tempted to spray WD40 everywhere. It can be a good cleaner, but it is a poor long term lubricant and will be difficult to clean off without dismantling everything.
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Old 5th Apr 2017, 8:40 am   #9
Mike Phelan
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Default Re: Metamec mains electric clocks - second hand erratic

Before doing anything, does the clock keep time?
That will prove whether the movement is running slow or if it's just the seconds hand.

If the former it is probably the rotor pivot that has 'gummy' oil making it struggle.

Again, we need a picture of the movement as Metamecs were made for quite a number of years.
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