Chronograph minute runner is slightly loose

[BrehmerR]

Hey! 
 

I am working on a really nice Accurist super waterproof 400 with a lovely landeron 51 movement. It runs really nicely overall but the chrono minute runner can move about 5 seconds to the right when reset as shown by the two different pictures on the movement below. I am guessing that the reset hammer does not contact the heart as it should. It does however contact the minute runner wheel perfectly. Do I need to shorten the end that contacts the minute wheel slightly to allow the other end to more firmly contact the minute runner heart or can this be regulated somehow? Maybe something else is the issue.

 

thanks for the help in beforehand!

[JohnR725]

Usually don't have to start modifying chronograph components unless you change something? Do you have a service manual for this watch? The reason I ask is chronographs tend to have a lot of things that look like screws that are not actually screws their offset adjustments to adjust usually the depth of things. Yon don't want to start filing modifying components until you made sure that everything is adjusting the way it's supposed to be adjusted.

[praezis]

I really wondered about which wheels you are talking!
chrono minute runner - minute runner wheel - minute wheel ?

There is a chronograph runner (seconds) and a minute recording runner (minutes). For understanding, better use the right terms.

Frank

 

[BrehmerR]

On 4/27/2022 at 7:51 AM, JohnR725 said:

Usually don't have to start modifying chronograph components unless you change something? Do you have a service manual for this watch? The reason I ask is chronographs tend to have a lot of things that look like screws that are not actually screws their offset adjustments to adjust usually the depth of things. Yon don't want to start filing modifying components until you made sure that everything is adjusting the way it's supposed to be adjusted.

Hi!
Sorry for the late reply. I have been pretty busy with some watches and have put this to the side for a bit.
I had not adjusten any of the eccentric screws before this problem surfaced. It was like that when I recieved the watch. 
It seems like the issue is that the hammer does not want to go all the way to the wheels to contact the hearts. Neither on the minutes wheel or the seconds wheel. Is there a way to adjust the length of the hammer movement so that it can contact the hearts better?

Once again, sorry for the late reply and thanks!

[JohnR725]

5 hours ago, BrehmerR said:

It seems like the issue is that the hammer does not want to go all the way to the wheels to contact the hearts. Neither on the minutes wheel or the seconds wheel. Is there a way to adjust the length of the hammer movement so that it can contact the hearts better?

Chronographs have challenges and you really need to understand everything before you adjust anything. Because if you start adjusting things without understanding the consequences you will have problems.

I have a parts list just in case you need parts don't know if the parts are available anymore chronograph parts tend to be a bit pricey just as chronograph movements can be really pricey

Then there's a book a light reading we get you started ill notice there's quite a few things to adjust is a certain degree of cause and effect C do have to be careful what you adjust

http://www.clubderelojeria.com/archivos/01LANDERON51.pdf

Then if the watch hasn't been serviced in a long time that might be part of the problem also. But servicing a chronograph isn't recommended for somebody new to watch repair.

ThenHas reminder for you and me because I would to save some time at I have done this originally always do a search on the group maybe someone is done something similar before like tracking down the service manual and a few words about adjusting things here.

Then there are probably other discussions on how to adjust the adjustments you just want to be really careful not to make mistakes. There usually is a procedure that's why there is usually a technical manual but we get a book that's nice and detailed

Landeron_Landeron 51 152.pdf

[Plato]

16 hours ago, BrehmerR said:

It seems like the issue is that the hammer does not want to go all the way to the wheels to contact the hearts. Neither on the minutes wheel or the seconds wheel. Is there a way to adjust the length of the hammer movement so that it can contact the hearts better?

The hammer should only come down fully on the chronograph runner (seconds) heart cam.

The extract is from 'The Chronograph' by B. Humbert.

[praezis]

 

On 4/25/2022 at 6:44 PM, BrehmerR said:

It does however contact the minute runner wheel perfectly.

On 5/19/2022 at 2:04 AM, BrehmerR said:

It seems like the issue is that the hammer does not want to go all the way to the wheels to contact the hearts. Neither on the minutes wheel or the seconds wheel.

You described two different issues. Please verify first which one is true for your watch.

Supposed no. 1:
This usually happens, when one of both chronograph wheels was changed without reusing the original heart.
Then the gaps between hammer and hearts are no more the same as before and reset does not work right anymore.
Remedy: one arm of the hammer must be ground shorter - until you get the conditions as described by Humbert above.

Plug and Play does not work with vintage chronographs!

Frank

Edited May 20, 2022 by praezis

[JohnR725]

17 minutes ago, praezis said:

Remedy: one arm of the hammer must be ground shorter - until you get the conditions as described by Humbert above.

I do have to wonder why were grinding a component in existing watch?

[praezis]

2 hours ago, JohnR725 said:

I do have to wonder why were grinding a component in existing watch?

Because the existing watch has no more all original parts for which the chrono mechanism was adjusted, please read again what I wrote. The new adjustment is needed to make it work correctly.

Frank

 

[JohnR725]

4 hours ago, praezis said:

please read again what I wrote.

I would say the same thing to you because I gave him the service manual for this watch so he can look at the adjustments recommended for the watch versus a generic book. No matter what I don't think people should be just grinding away on hearts that if you destroy are not going to be replaced and you need to understand exactly what you're doing. Because getting another part is going to be difficult and no I don't usually read all the fine print in everything I answer

[praezis]

Quote

and you need to understand exactly what you're doing.

 Exactly. And one who does, with knowledge of chronographs, will find that fiddling with eccentrics is useless with issues that I called no. 1. 

Frank

[nickelsilver]

I do several chronographs of all flavors each week, and a few times a year I have to file (and polish) certain functions. One test I always do is if the hammer hits the chrono runner and minute counter correctly. I file these functions probably once per year. Why? No idea, but if needed, I file, as I want the watch to go out working correctly.

 

Before removing metal in a watch, check _every possible thing_ that could affect that function. Here, a big one is if the post for the hammer is securely screwed in. But at any rate, quadruple check- you can file hammers maybe 2, 3 times before they're a goner (figuring pro level filing). Take your time, check and recheck. Normally unless parts have been swapped no filing necessary in a service.