My Tissot chronograph (still haven't figured out what ref. it is...) is at the watchmaker at the moment, since it has exhibited an annoyingly persistent periodically occuring fault.

Click on the picture to go to the video:


Tissot Chronograph by Troels Ølholm, on Flickr

Apparently, there is also an issue with the heart-shaped cam for the hour recorder - can anyone with the technical insight tell me more? Also, I shall be writing him later tonight, but does the fault mentioned explain the issue with the chronograph needing the reset pusher activated in order to start, or is it related to the misplaced hour recorder hand?

 

I really hate to do this, but... @Archer , do you think you could have a look at this? I always scoff when people on here light up the Archer-light on the sky and you come to the rescue, but I would really like some technical insight here. The fault does not materialise when it's at my watchmaker

 

Was just curious, @ConElPueblo, if you had figured out the intermittant problem.

 

I still have no idea what's happening. As mentioned, it doesn't appear when it's at the watchmaker's, which is hugely annoying... Would still love to get some input from this site's watchmakers, perhaps @Horlogerie knows what's up?

 

What a strange problem! I had an issue with one where the chrono would only engage if the Operating Lever was loosened off. The watchmaker suspected that an incorrect screw that was too long had been used which was pushing the operating lever up when the screw was tightened.

 

@oddboy was that error consistent? Or was it occurring erratically? The fault on mine occurs periodically, which is even more frustrating than a full-on defect

 

It was pretty consistent until the overhaul. After that, and using correct screws, it was fine.

 

I thought it was going to easy to find your ref but my Google-fu failed. Usually Lemania originals print the ref on the inside caseback. But going from my picture search tissot seem to have a case number by the looks of it. So I have few thoughts.

1 Drop tissot an email with images and hope the have access to an archive of sorts.

2 Just get it serviced probably due a spa anyway. As your watchmaker knows there is chrono issue he can keep an eye out for irregularities.

3 i saw some possible donors online so you could get part raiding if need be.

4 Post spa my bet is on this One! when you do another timing/accuracy run.

Good luck.




Sent from my D5803 using Tapatalk

 

The watch has JUST been serviced - it was only after the service that the issues became apparent. It had other issues before, so I don't think it's his fault. It is with him now.

The problem with the starting issue is that it doesn't happen all the time. It hasn't happened while he has had it in custody. The hour creep problem has been identified...

 

Ok,
It's been for a service, and returned to you.
Watch presents a new intermittent fault.
You made the video.
Returned watch to watchmaker.

I presume you have shared the video with him. So he can see the fault present.

Intermittency is a problem, in any situation. We are seeing a fault we cannot define accurately.

Hope one of the legends you mentioned swing by to share their expertise.

I really hope it gets fixed, this beauty deserves to work as intended.







Sent from my D5803 using Tapatalk

 

Here's the part in question:


The cam on the side of the wheel at the top left is worn, which makes it unable to reset to twelve properly.

 

Any chance of getting the part number or proper name for the part you need?

 

Also thinking the same.
And I'd also get rock solid confirmation it's 27chro 12ch.
I had go at part list but the above has an additional hole.
NOTE, just someone trying to be helpful. Complete newbi, infact consider me a labrador or a small child. That has access to the Internet.


This is 321 not the correct sheet IMHO, as part shown in picture above has one extra hole. Watchmaker question if part can be used as a sub, modified by clever watchmaker magic or just wrong...

https://www.google.co.uk/url?sa=t&s...pogKekrhJ1k32MiBw&sig2=or08kbFBCko5jeNhDVPeMA

Woof woof
P


Sent from my D5803 using Tapatalk

 

Bingo bango bongo...every dog has a day in the sun.

This one is a better candidate, it has 5 holes. And listed as the 27chrono c12 and not the Omega variant. Lemania 4 the maniac in me... [emoji16]

Same disclaimer as above...Woof woof

https://www.google.co.uk/url?sa=t&s...gZiKXJXQpuCyp5cKA&sig2=5unjzkjhDl9LGJeS2E2pTA


Sent from my D5803 using Tapatalk

 

So am I correct that you have 3 problems with this watch?

1 - Hour recorder creep
2 - Hour recorder not resetting
3 - Chronograph may not start without pushing the reset button at times

1 - So hour recorder creep is often resolved with just an adjustment. In fairly rare cases (in my experience) the hour recorder runner (the part with the cam on it) can have worn teeth, or the hour recorder stop lever and also be worn to the point where one or both need replacing to resolve this, but again rare.

2 - Someone has told you (?) that the cam on the hour recorder is worn. I often find wear on these if it's like this:



Depending on the severity of the wear, I will replace it. But it's not clear to me this is the reason for the hand not being aligned - it could just be that the hand is not installed properly. If there is going to be variation in the resetting of the hand, it's usually going to be the hour recorder that has it, just from the way it functions. When the hands are all reset after being stopped, the minute and seconds recorders have the hammer (the part that resets the hands via the cams) come to rest and "hold" the cams in place. The hour recorder does not work this way - the hammer for that swings in to reset the cam, but as you release the pusher it swings away from the cam, and the stop lever takes over to hold the hour recorder runner from being turned by the mainspring barrel.

3 - I don't think 1 and 2 are necessarily related to 3. Intermittent problems are the toughest to resolve, and I'm not sure how used to working on these your watchmaker is, but I would first be checking all the chronograph controls. These are a series of checks done to ensure the chronograph system is set up correctly, so engagement of teeth, freedom of the friction spring, gaps at the cams, alignment of jumpers, etc. and should be done at every service.

If I had to guess on this specific problem, it looks to me like coupling yoke is hanging up and not moving in on it's own to engage with the main chronograph runner. So I would make sure the coupling yoke spring is installed correctly, and is pushing on the coupling yoke. The screw that holds the coupling yoke assembly to the bridge can be problematic - it's a shoulder screw of a specific height and if the wrong screw is installed, it might be binding on the yoke and not letting it swing in. I have also seen that even with the right screw installed, if someone in the past has cranked down on it really hard, it will sort of wear or make a divot in the brass bridge, so the screw goes down to far and again binds on the yoke.

So when you are pushing on the reset pusher, it's jostling the parts around enough to allow the yoke to swing in and start the chronograph. So again my feeling is that this has nothing to do with the hour recorder problems, and just replacing the hour recorder runner will not solve this...

Cheers, Al

 

Your torch is working. Magic man has a long list for you.....

Thanks @Archer Al for your insight.. Good to have 2nd doctors o....pinion. Punkt the punn. (Both puns intended)

Is the second (link 2) part list a good starting point should spares be needed?


I'm sure ConElPueblo will be by sortly. He's probably not looking at his computer on account he banging on a door somewhere. [emoji110] [emoji110]




Sent from my D5803 using Tapatalk

 

Thanks @Archer and @tapaptpat for the replies

Archer, the problems are

1) that the chronograph hours hand does not reset to 12 (or "0", really), but a bit further than that. My watchmaker (Christian @ Watchguy) says that

2) that, periodically, the reset pusher will have to be depressed in order to engage the chronograph. As it is a periodically occuring fault, it has naturally failed to manifest whilst with Christian

I do not know if you can make anything out of the photos from the service, but here they are anyway.

 

I know Christian - I don't email with him much anymore, but I used to help him with problems like these directly, so I guess I'm just doing the same thing but through the forum...

Okay so there is no hour recorder creep then? I ask because you said this in a post above:

"The hour creep problem has been identified..."

I can't tell if the cam is worn or not as it would need to be a closer shot of it than is included in his photos. If he says it's worn, then it's worn. Is it causing the hand not to reset properly? I can't say...

On the other problem of having to press the reset button on occasion, above I said this:

"I have also seen that even with the right screw installed, if someone in the past has cranked down on it really hard, it will sort of wear or make a divot in the brass bridge, so the screw goes down to far and again binds on the yoke."

And there's only one photo in those that shows this area, but it looks like someone has cranked this down hard at some point, as I don't believe the bridge should be worn there:



BTW if this really based on the same movement as the Omega 320/321 as it appears to be, then I believe the lift angle should be 40, not 42 degrees, so the amplitudes are possibly lower than the machine would suggest by about 12 degrees. If that second timing machine shot is after service, it's pretty low...corrected it would be 255, and it's not clear if the chronograph drive wheel, coupling yoke, and spring have been mounted when those readings were taken - if not the amplitude would drop even further.

I currently have a 321 here with amplitudes a bit higher than these and I'm still working on getting them higher...

Anyway, have him check the freedom of the coupling yoke under the screw that holds it in place. If the bridge is worn or has a depression, or even if there is a raised burr there, it may be interfering with the yoke coming across properly.

Cheers, Al

 

Al, thank you very much for your very detailed answer. It's a privilege to have you here and I'm grateful that you took time to look into this

 

I'll second that!