# Accutron 2185 running slow - battery?



## kidblue (Dec 10, 2008)

Lots of conflicting reports out there - is it possible for an Accutron to lose tons (dozens of minutes per day) time over the course of weeks due to a failing/low battery?


----------



## UK humbug (Feb 19, 2016)

Perhaps this may be viewed as a facetious reply, but just replacing the battery will answer your question.


----------



## kidblue (Dec 10, 2008)

Yeah, that'll answer the question in a broad sense, but I was actually looking for a reason why over time a failing battery would cause this kind of reaction specifically



UK humbug said:


> Perhaps this may be viewed as a facetious reply, but just replacing the battery will answer your question.


Sent from my iPhone using Tapatalk


----------



## UK humbug (Feb 19, 2016)

Hopefully the more detailed explanations that have been given on the other forum where you have raised this question have provided you with the answer/s you were seeking.


----------



## kidblue (Dec 10, 2008)

UK humbug said:


> Hopefully the more detailed explanations that have been given on the other forum where you have raised this question have provided you with the answer/s you were seeking.


Yeah, they were very articulate and detailed. Exactly what I was looking for and weren't snarky at all. Thanks for asking.


----------



## SAM2 (Apr 14, 2010)

The answer is a resounding NO! That's not how Accutrons work but if a fresh battery resolves the issue, let us know. It wouldn't be the first time I've had to eat my words.


----------



## marks55 (Apr 11, 2012)

Dozens of minutes? I wouldn't exactly call that slow; I'd call it not running. Are you sure it's not stopping? 
Sounds vaguely like a service (in need of) issue. It doesn't sound like a battery problem, if the battery is dead it just won't run at all.
As suggested, I'd just change it and proceed from there.


----------



## kidblue (Dec 10, 2008)

Not stopping at all, just running very slow. I'm actually interested in the question from an engineering perspective, since amplitude can decrease with voltage over time and unlike a conventional stepping motor, these movements are much more efficient and likely to slip multiple teeth, right? Or have a decrease in amplitude from where a battery is seated, if it needs a "jump start" of the fork, etc.

Of course, the battery issue can be determined with a change - the question is whether this kind of performance (or lack) is possible due to an "old" (low voltage) battery, especially when using a 1.5v as opposed to 1.35v, etc.



marks55 said:


> Dozens of minutes? I wouldn't exactly call that slow; I'd call it not running. Are you sure it's not stopping?
> Sounds vaguely like a service (in need of) issue. It doesn't sound like a battery problem, if the battery is dead it just won't run at all.
> As suggested, I'd just change it and proceed from there.


----------



## odd_and_vintage_fan (Dec 4, 2014)

From the engineering standpoint, if the movement was phased so that the amplitude from a 100% fresh 1.5V battery juuuuust barely drew the one tooth it needed to on 0.83% of the cycles within the distribution curve of the amplitude of each cycle, then any drop in voltage would cause it to not push the tooth on those cycles causing 12 min/day slow.

It might just need to be re-phased so the pawl finger pushes somewhere more in the middle of the acceptable range and not on the low end.

What battery life did you get out of the last one?


----------



## kidblue (Dec 10, 2008)

Battery life is unknown, since I just got the thing a few months ago - I am new to Accutron movements, which is why I'm interested in the actual causation/effect rather than just "try a new battery" - I really appreciate the attention.

It is using a 344 (1.5v) and had been keeping good time, so it was either re-phased or is simply one of the 218's that responds within spec to newer batteries.

To speak to your explanation, if the battery itself was operating at less than 100%, i.e. was nearing the end of its life, could that account for the drop of voltage/amplitude and the slowing down of the movement? On another forum, I read that unworn, the magnets need a "smack" every once in a while to get back to vibrating within spec. Is this a thing?



odd_and_vintage_fan said:


> From the engineering standpoint, if the movement was phased so that the amplitude from a 100% fresh 1.5V battery juuuuust barely drew the one tooth it needed to on 0.83% of the cycles within the distribution curve of the amplitude of each cycle, then any drop in voltage would cause it to not push the tooth on those cycles causing 12 min/day slow.
> 
> It might just need to be re-phased so the pawl finger pushes somewhere more in the middle of the acceptable range and not on the low end.
> 
> What battery life did you get out of the last one?


----------



## Accu-man (Jan 11, 2017)

Have you checked to see if the second hand is losing time as well? If the second hand is keeping time and the hour and second hands are not, then most likely it's the cannon pinion slipping. 

Sent from my SAMSUNG-SM-N920A using Tapatalk


----------



## odd_and_vintage_fan (Dec 4, 2014)

kidblue said:


> Battery life is unknown, since I just got the thing a few months ago - I am new to Accutron movements, which is why I'm interested in the actual causation/effect rather than just "try a new battery" - I really appreciate the attention.
> 
> It is using a 344 (1.5v) and had been keeping good time, so it was either re-phased or is simply one of the 218's that responds within spec to newer batteries.
> 
> To speak to your explanation, if the battery itself was operating at less than 100%, i.e. was nearing the end of its life, could that account for the drop of voltage/amplitude and the slowing down of the movement? On another forum, I read that unworn, the magnets need a "smack" every once in a while to get back to vibrating within spec. Is this a thing?


Good call to Accu-man on the cannon pinion possibility.

My understanding of the "smack" technique is it's for when replacing the battery. Based on something I don't fully understand with the feedback loop to provide power to the correct coil at the correct time to maintain amplitude, it's possible to put power into the system and have nothing happen. The "smack" to the 9 o'clock side starts the system going and it takes off from there.

I've never heard of the magnets needing an occasional jostle otherwise, but mine gets worn about once a week and has never sat long-term. Others on here have larger collections where an individual piece might not get worn for a few months. They might know better.

If it's new to you, it might be due for a service. When I first got mine, it ran beautifully for three months, started losing time here and there, then would randomly stop altogether. After a service, it's gone two years with just battery changes and runs about 1.5 s/day fast.

These little things are certainly a labor of love to keep going strong. In my experience, it's worth it, though.


----------



## kidblue (Dec 10, 2008)

Yeah, I'm very into making this Accutron a part of my collection, which also means a part of the rotation of service and maintenance! That said, it's the kind of movement I know so little about, a little "detective work" into how it's malfunctioning could help me in the future and also satisfy my need to know a little bit about what I like to collect!

To answer above - The second hand seems to be running well, although a little slow - If I had to guess, the whole shebang is losing time!

It could easily need a service, although I did give it a smack after replacing the current battery and it seemed to run better for a day - does that seem to mean anything?


----------



## Molliedooker (Jul 23, 2014)

Do you have an iPad ,iPhone or equivalent. Of course you do.
Go to the "stop watch " function ,mine is in the clock app. and exactly when the second hand on your watch hits 12 press the green / start button and see if it hits 12 as each 60secs turns over on the stop watch . Run for 15 mins to get a clear idea what it's doing.


----------

