Reply With QuoteLeave them stopped when they are not in use.
Do you sync the chrono with seconds and leave it running or leave it stopped?
Does it make any difference to the "health" of the movement?
Leave them stopped when they are not in use.
I have heard that for seiko movements with vertical clutches it is better to leave them running
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I have read advice that supports both.
My personal preference is to have them running.
I think from previous threads on the subject the advice seems to be to leave them stopped.
Probably depends which ones they are.Originally Posted by Wallasey Runner
A number of people with Pogues keep them running.
Last edited by Velorum; 23rd April 2017 at 16:00. Reason: missing words, missing words
I assume this would use more of the power reserve as well to keep the chrono running?
Yes, it was probably the usual suspects: Daytona and Speedmaster
Would you leave your car engine running when you are not using it? Come to think of it, is there any mechanjsm you leave running when it is not being used? The more things are used, the more they run down and wear out.
My understanding is vertical clutch ones yes (so Seikos and Daytona), the non ones no (so the 7750 movements). Probably more nuanced than that which someone will correct me.
Despite having assembled a few I've never given this much thought. From a wear point of view, the chronograph runner will be engaged and turning, and the centre seconds (chrono) wheel is running. However, that's a similar analogy to a centre seconds hand on a normal 3 hander and unless the watch hasn't been oiled in living memory it shouldn't suffer from extra wear.
Sometimes the amplitude is adversely affected when the chrono is engaged. That's due to the extra drag involved in turning more parts and this is more of a factor if the watch needs service or if it isn't adjusted correctly. Some movements are affected more than others, but provided the movement's healthy it should only be a few degrees and that won't affect the timekeeping. If the watch hasn't been serviced for donkeys years the amplitude will be low and running the chrono will push it lower, so the effect will be more significant.
For reasons I can't fully justify I always leave the chrono turned off unless I'm timing something.
Paul
I think that it is counter intuitive to many - hence the car engine analogy in a previous post.
I agree with this, but it does annoy me that the main second hand (on the Chrono) sits idle, whilst the Sub dial does all the work. Couldn't they make them the other way round and effectively be a three handed watch and when you use the Chrono function the seconds Sub dial would kick in.
In the likes of Omega promo clips of new Speedmasters, they always have the big Chrono second hand running.
There are a few exceptions (as already mentioned) but generally leave stopped unless timing something.
Andy
Wanted - Damasko DC57
If you think about it that is a poor analogy. Firstly, a watch mechanism, of which there are many types, is actually very different to a car engine in construction and operation. Secondly, would you expect to leave your car untouched for 6 months and then for it to perform at a peak level instantly? Quite a few wouldn't even start, the brake disks would have corrosion on them, the fuel may have degraded, all the oil would be in the sump etc.
Whereas a chrono is supposed to time accurately at 0.1s increments or better.
Personally I generally don't leave my chronos running but do use them every few weeks. I doubt that makes much difference but I like doing it anyway.
I have only three autos and they share wrist time with 7 other watches. Two are plus 20 years old have each received 3 overhauls (7750 and 7757). Both have sat untouched for years at a time and when I did pick one up to wear, I wind it and it starts working without issue. One is an Omega Speedmaster and the other a Memosail Skipper Jubilee.
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I find the watch / car engine a bit counter intuitive because cars aren't really designed to be run 24/7, and they aren't the most similar mechanisms in the world.
A chronograph mechanism's closest analogue is probably a watch mechanism. Those are designed to be running 24/7 and for the most part, they do so just fine. I don't see mechanically why they are all that different, so I don't think running it constantly is beyond its designed tolerance.
That is different to saying that a chronograph (or watch in general) would last longer reliably if it runs constantly versus regularly - for that I don't know.
Naturally, running the chrono mechanism will put more wear on it than if you don't. But the main watch mechanism is running 24/7, as you say, and so will need servicing before the chrono parts do. So keeping the chrono stopped won't make any difference to the service interval.
That said, I don't see the point of keeping it running if you're not timing something. Why would you?
The only rationale I can think of for running the chronograph constantly is if it improves timekeeping, which just depends on how the base movement is regulated. The trade off is possibly reduced power reserve, though that might be marginal or nonexistent. one of my El primers runs 5s fast per day with the chronograph off and practically dead on with the chronograph running. But I don't wear it every day so I don't care either way.
I never even realised people did this. When I first got a chronograph I couldn't understand why the big second hand wasn't going round until I popped into a jeweller and they explained. I've got 2, one is quartz so I assume having it on would run the battery down quicker.
Having the chrono running on a mechanical watch will have negligable effect on power reserve.
Paul
I leave the chronograph off due to a watchmaker once advising me that it leads to more wear and tear. I think mine keeps slightly better time when the chronograph is off too, so win win.
If you own a chrono you should have researched the watch and know how to treat the movement.
F.T.F.A.
Thinking through it more, we can look at the chronograph mechanism's components to see where wear might take place and whether it is very dissimilar to normal watch movement operation. This is all just my thoughts and I am not a watchmaker so please do add your thoughts or corrections as I'd love to learn more too.
the parts that would receive wear are
-Horizontal clutch wheel or vertical clutch
Can't see this as being an unusual amount of wear, depending on the movement - e.g. El primero intermediate gear is jewelled just like a normal running train gear so should be similar to the rest of the movement. For vertical clutch systems like F.piguet the clutch itself is constantly being driven anyway, it's just whether it is engaged with the chronograph seconds or not
-Central seconds mechanism
I would guess that this is rather like normal central seconds, except it also drives the other chronograph counters
-Minute/hour accumulators
The accumulator mechanism I understand is driven not completely unlike a date mechanism, so this is something that might be getting rather more wear than an analogous part in a standard movement. Having said that, there might be rather less energy involved in triggering an accumulator for a small chronograph sundial hand than there is for a full date wheel. Some chronograph do use wheels rather than hands like the Tag Rs and some Jlc pieces...
Depending on whether the tripping mechanism is more of a tooth (like the El primero) or a wire (like the f piglet) could the latter deform over constant use? this is a good question of whether it's designed to trip the minute accumulator 1440 times a day or not but maybe the energy required is so tiny it doesn't matter for service intervals. Any thoughts?
-Reset mechanism
I'm a bit limited in my understanding here, but if I'm not mistaken the typical reset mechanism is not doing anything whether the chronograph is running or not.
Note that all of this applies to normal chronographs, I don't know if anything different would apply to flyback or split seconds?
When the chronograph doesn't need to be used, stop it, and reset it.
Agreed, I'd prefer an always running large central seconds hand too. All too often people think my watch has stopped because the large second hand is stopped at the 12 o'clock position.
I like them running on watches that don't have a second hand, e.g. Chronostop and flightmaster 910. Gives the watch a bit more 'life'.
I read the other day that the Journe Centigraphe's power reserve of 5 days was reduced to 24 hours if the chrono was running constantly. Would that be massively incorrect information or because it's running 3 chrono counters. Surely, it must have some effect?
It would be a lot harder to accurately time anything if the chrono seconds were the small dial surely ? I even notice this on one of my chronos where the minutes counter "snaps" to each minute vs one the continuously moves.
Given for most people they are a gimmick can see that appeal and agree the large parked hand can look a little odd.
This would be my feeling, too. The watch is workig all the timne because we want to know what the time is. If it's not being used for it's intended purpose, there seems no reason to have it running...
Actually, the idea of leaving a chronograph running had never even occurred to me.
Simon
I always leave my chronograph running with my watch on a winder.
Just a joke. I only have one mechanical chronograph anyway, which was my stepfather's Seiko bought in the late 60s and never serviced, so far as I'm aware. He gave it to me a few years ago; I had thought it wasn't working at all but it turns out the chronograph is working. I know for sure he didn't leave it running all the time. Anecdote, not data, but I can't see why you'd leave a chrono running; if you ever wanted to use it you'd have to reset it before starting it anyway and isn't that bound to cause more wear, ignoring the potential for more wear when it's simply running constantly?
This Youtube video covering Seiko 6138/9 calibres is relevant:
https://www.youtube.com/watch?v=pHxB8SqwZsw
Regarding 7750 movements, I think I recall reading somewhere that the chrono hour hand doesn't have a jewelled bearing.
The actual auto movement keeps on running when your sleeping that's why we use watch winders. Can't think why chrono function running would be any different
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Stopped, because it's seriously goofy to leave the thing running all the time for no reason.
No — or at least not enough to actually matter in real life.Does it make any difference to the "health" of the movement?
Does anyone actually does use the chrono function these days? Other than timing the cooking that is.
^
Yes. It's a more useful complication than most.
That is rather an interesting video. I hadn't realized that vertical clutch systems such as that in the Seiko movements relied on a spring, and that the spring was in the stressed position when the chronograph was disengaged
I asked a friend of mine who has some experience with materials and springs. He said that of course it depends on the spring (material, shape, etc) but that keeping springs in the stressed position does cause them to lose their tension (i.e. ability to return to the original shape). This depends significantly on how 'stressed' the spring is, i.e. if the part is designed so that the compression is only a small percentage of its strength, then it is less deformative. The effect is logarithmic, i.e. exponentially decreasing, and springs can be pre-stressed during their manufacture anyway so that when they are actually deployed the absolute deformation is smaller. Nonetheless, compression over decades is certainly going to have an effect.
Note that engaging/disengaging or relaxing/stressing the spring in most conditions does not have any meaningful impact compare to holding under constant stress for these kinds of springs.
So for such systems it may be more beneficial to, as the video says, keep the chronograph running constantly. Other vertical clutch mechanisms such as the F.Piguet series I believe do not use springs in the vertical clutch system from what I can see, but I am happy to be corrected on this.
For horizontal clutch / intermedite gear systems like the El Primero, I understand there is a spring-tension device (kind of like a bar or wire) which is part of the column wheel switching mechanism but this is only stressed when actually engaging/disengaging and stays in its normal position whether running/stopped.
I think that should be right, as usually when I see movements with bi-compax and tri-compax versions, both have similar jewel counts - I believe it is the case for the 7750 and it is shown to be the case for the El Primero. For that matter I am not even sure if minute accumulator wheels are jewelled - even if left constantly running it 'only' would move 1,440 times per day, as opposed to around 700,000 times per day for an escapement wheel. Nonetheless this does constitute extra wear on un-jewelled components.
So perhaps the summary for now is:
-Certain movements with spring-based vertical clutches benefit from constantly running but this does not apply to all vertical clutch movements
-For horizontal clutch movements this doesn't appear to be an issue
-For cam/lever chronographs also not sure
-For the interface between the running seconds and the chronograph seconds, this functions similar to other parts of the watch so probably okay to keep running
-For the accumulators, don't know - it's more wear than they would otherwise get of course, but apart from a date accumulator it's hard to find a good analogue in the watch movement and date wheels naturally don't change often
For me personally I wouldn't feel nervous at all about running the movement constantly on a normal watch - it's extra wear, sure, but I think it's not outside of what it's designed for. If I had some super rare or expensive chronograph I probably wouldn't, but then again I probably wouldn't be wearing it that often anyway.
Don`t overlook the importance of lubrication! You can pontificate ad nauseum about the potential for wear on jewelled or unjewelled bearings etc etc but if the lubrication's inadequate all bets are off.
This is where the 'if it ain't broke' argument against servicing watches falls down; lubrication is vital to minimise wear but some folks cling to the belief that a watch shouldn`t be disturbed until it's well and truly poorly.
Perhaps the high cost of servicing watches thesedays helps reinforce their belief......or am I being cynical again?
Run the chrono if you like, don`t run it if you don`t but above all else ensure the watch has been serviced within living memory.
Paul
To echo what Paul said, I've just had my 7750 PD chronograph on my timegrapher and the amplitude is around ten degrees lower with the chronograph running (275 as against 285).
Clearly this isn't too important with a recently serviced movement bug far more important as it gets closer to its next service.
These amplitude figures are in line with what I`d expect to see from a 7750 that's running well. Start worrying if it drops by 40° with the chrono running, that's usually down to the adjustment not being correct.
Paul
I was thinking more along the lines of when the amplitude is down to 220ish. Losing another ten degrees is going to be bad for the timekeeping. I hadn't actually considered that you could possibly lose a lot more amplitude when ready for a service although it does make sense.
I don't think it's goofy to have the central second hand running like it's an actual second hand. At my age subdial seconds require a telescope
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^
Are you timing something? Because if you want to keep track of something to the second using a centrally-mounted hand, chronographs do have a provision to perform exactly that function when needed. :D
Running is wear and tear
But no more than the rest of the movement and it will all be serviced at the same time.
i read from the US Seiko AD (manager?) that as Seiko uses a proprietary alloy (SPRON), the mainspring need not be replaced for a very long time because it does not wear like conventional mainsprings.
it would be conceivable that they used a similar alloy for such "high wear" wire springs else where...
That's a good way of putting it.
The Swiss used to recommend not running the Landeron chronograph constantly in the 50's and 60's and suggested winding the watch fully before timing events.
It lowers the amplitude by about 20-30°.
In my experience most wear occurs to the heads of the return hammers and the tiny pin which advances the minute recording wheel.
Some of the more recent chronographs like JleC and Frédéric Piguet have such vicious zero return springs that the chrono hands have to be attached incredibly tightly and are almost impossible to remove.
I get the impression that some Breitling and Omega models deliberately fit the hands tightly so that you have to send the watch back to them for repair.
This violent reset sometimes cracks the jewel holes or breaks pivots. For example on early Zenith Primeros.
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Last edited by Webwatchmaker; 4th May 2017 at 09:04.
Leave it stopped unless I'm timing something.
I only have the chronograph engaged when I'm timing something otherwise I simply don't need to know the time to the second in normal use. The seconds hand is mainly useful day to day to see if the watch is running and so it hiding in a sub-dial is enough.
Interesting comments from Brendan regarding how tight the hands are fitted on some chronos!
The likes of Omega will always fit a new handset at service time, which seems a bit daft to me if it's not necessary. However, no matter how carefully they're removed there is always a risk that a hand gets slightly distorted when they're so tight to get off, so I guess there's some logic in this.
Worst ones I`ve come across recently were on a TAG quartz chrono. I got them off without damage but it was difficult to say the least! God knows how they were fitted originally; I was replacing the movement and I actually had to broach one one the sub-dial hands slightly to press it on......that really shouldn't be necessary.
Brndan's right about the strength of the flyback action on some watches. The chrono hand has to be tight otherwise it'll move slightly when the chrono is reset. Getting the chrono hand lined up exactly at zero takes patience, it's nowhere near as easy as folks may think. Once you're convinced it's correct the hand has to be pressed fully home......and if it turns out to be slightly out the process starts again.
I`m not a fan of chronos to work on, can`t say I enjoy it. Far more demanding than ordinary 3 handers unless you're a genuine watch-god......which I never claim to be!
So next time you look at your recently serviced chronograph, spare a thought for the dude who refitted those hands!
Paul
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