1934 40mm Longines Cal 15 chronograph

AdamVT227 · Oct 7, 2024

DirtyDozen12
I am not sure that I would send this watch to be serviced by Longines in Switzerland. The primary motivation for doing so, in my opinion, is in order to access spare parts that are very difficult to find elsewhere. In this instance, the only part that is apparently needed (though there may be more) is the jumper spring. Assuming that Longines actually has this part in stock, which I am not sure of, the price to acquire it will be very high since a full service will be obligatory. I would recommend taking your time to figure out what you ultimately want to do with the watch, prior to deciding what to do about servicing it. If you intend to sell it, then it may make more sense to leave the watch as-is, to minimize your investment and the risk of any damage.

Syrte
Agree with @DirtyDozen12 it’s worth taking a bit of time to figure out what you’d like to do with it.
And we’d probably all agree that if you decide to sell it, then it’s best to leave it alone.

If this is a Valjoux part perhaps one could research donor movements and restore with the help of a talented independent watchmaker.
For those who are interested in those kinds of projects, @w154 undertook such a venture -but it was much more intense and dramatic.
http://www.onthedash.com/abercrombie-seafarer-first/

I must say it is quite tempting to send it to Longines but i personally can't pay that much for a service currently .

I'm not in a rush with this watch ill have a think about all my options ,
I have a very good local watchmaker that i'll visit with the watch and ask him his thoughts and if he feels comfortable with servicing it .
as for the missing part I can see that i can buy a complete watch with a Valjoux 22gh for less then 1k (but without a nice finish) , i'll be on the hunt.

anyone here has a spare Valjoux 22GH ? 😅😅

DirtyDozen12 · Oct 7, 2024

P.S. Looking superficially at the more common Valjoux 22, it is possible that it uses a spring that is interchangeable with the equivalent part on a Valjoux 22GH. I am not at all sure about this, though. But this would make the task of locating a functional (if not visually coherent) replacement part much easier.

AdamVT227 · Oct 7, 2024

DirtyDozen12
P.S. Looking superficially at the more common Valjoux 22, it is possible that it uses a spring that is interchangeable with the equivalent part on a Valjoux 22GH. I am not at all sure about this, though. But this would make the task of locating a functional (if not visually coherent) replacement part much easier.

i must say that on the longines movements on this thread the tip of the spring that sits on the teeth looks different then the valjoux one , both the 22 and the 22gh

AdamVT227 · Oct 7, 2024

AdamVT227
i must say that on the longines movements on this thread the tip of the spring that sits on the teeth looks different then the valjoux one , both the 22 and the 22gh

but tbh it looks different on almost every movement , even on the longines ones . so , hard to tell

DirtyDozen12 · Oct 7, 2024

AdamVT227
but tbh it looks different on almost every movement , even on the longines ones . so , hard to tell

Agreed, there seems to be a lot of variation. I will add a photo comparison below, but hard to say that these springs are representative of their respective calibers.

AdamVT227 · Oct 7, 2024

DirtyDozen12
Agreed, there seems to be a lot of variation. I will add a photo comparison below, but hard to say that these springs are representative of their respective calibers.

thanks for the comparison , i found this one on ebay and the shape looks pretty similar . but it is not cheap , and if it wont fit then its a big waste of money
https://www.ebay.com/itm/225029698476

DirtyDozen12 · Oct 7, 2024

AdamVT227
thanks for the comparison , i found this one on ebay and the shape looks pretty similar . but it is not cheap , and if it wont fit then its a big waste of money
https://www.ebay.com/itm/225029698476

I saw that one too, but I am not totally certain that it will work, so I would do more research before committing.

AdamVT227 · Oct 7, 2024

@DirtyDozen12 found this video on youtube of a guy servicing a valjoux cal 22
at 8:20 he removes it and all the way till 9:00 you can see the placing holes
at 29:18 he puts it back

the second video is the same guy servicing a lower grade finish cal 22 and the spring looks similar to the longines above .
he removes it at 8:00

The placement holes looks the same in both watches
I'll remove mine tomorrow and take some photos for comparison .

edit : theres some more videos on youtube on cal 22 and all the different tip shapes seems to have the same placing

1#-

2#-

DirtyDozen12 · Oct 7, 2024

Good research, thanks for sharing! I think that comparing these movements with yours is ideal.

DirtyDozen12 · Oct 7, 2024

P.S. Here is a comparison between one of the Valjoux 22 movements above and a Zenith-modified Valjoux 22GH (from here: https://omegaforums.net/threads/zenith-monopulsante-valjoux-22gh.57910/). It looks like the distance between the holes is similar, but it is tough to tell if the position is the same relative to the straight edge of the bridge beneath.

AdamVT227 · Oct 8, 2024

@DirtyDozen12
So here are some photos from my Longines :

Then I thought of checking the angle on a few examples :

My Longines :

the 2 Valjoux from youtube :

and finally the 22GH Zenith :

all was made by a naked eye so not very accurate but I do think I can now say that the Valjoux 22 jumper spring seats the same as the Longines .
Sadly we cant see the original Zenith part but it was definitely different .

Now the only uncertainty left is the tip shape , but I think all of them will work the same .

Radiumpassion · Oct 8, 2024

This tread will certainly hjelp someone with the same problem in the future. Great stuff👍

DirtyDozen12 · Oct 8, 2024

Really great work! And I agree with your conclusion, it does look like the Valjoux 22 and Valjoux 22GH (Longines) use springs that seat the same. Below, I have added a comparison between the Valjoux 22 spring from eBay and the spring base from your Longines.

AdamVT227 · Oct 8, 2024

DirtyDozen12
Really great work! And I agree with your conclusion, it does look like the Valjoux 22 and Valjoux 22GH (Longines) use springs that seat the same. Below, I have added a comparison between the Valjoux 22 spring from eBay and the spring base from your Longines.

Thanks ! i really appreciate the time and effort you put into helping me on this subject .
I found a cheap one , seller says nos but has some rust , i will try it to see that everything works well and maybe its even salvageable .

I know i would probably have a couple more questions on the restoration later on but i think for now i'll wait for the part to come and continue from there .

Larry S · Oct 8, 2024

First WOW! Amazing catch. Where are you based? If US based and your guy doesn’t want the job, I’d send this to RGM in Mt Joy PA.

AdamVT227 · Oct 9, 2024

Larry S
First WOW! Amazing catch. Where are you based? If US based and your guy doesn’t want the job, I’d send this to RGM in Mt Joy PA.

Thanks , I'm not located in the states .
If my local watchmaker won’t take this project then flying to Europe is closer for me .

AdamVT227 · Nov 8, 2024

Earlier this week the jumper spring arrived , and today I tried checking if it fits .

So , it is slightly different from the original .

The placement feet is not the same by a very tiny margin , cant see the difference with a naked eye , but when I first tried to place it , it didn’t wanted to go in it’s place , while the original went smoothly .
with some willingness it did got in it’s place .

Then I checked while the chrono running if the minutes register works well , and it did ! 😀

Now I need to take it to my watchmaker for a service , will take some time ,he is very busy and said to me to check with him next month .

AdamVT227 · Nov 8, 2024

Before servicing it I have 2 questions :

1. is this the original crystal ? it has deformed a bit so even after a polish it won’t be nice .
But if this is the original then i would probably leave is on and just polish it a little .

Added some photos of the crystal .

2. Cleaning the dial ?

I assume that because it is an enamel dial it can be cleaned vey nicely by removing dirt and all other kind of residue on it .

what is the best way of cleaning such a dial ?

asked my watchmaker how he does it and he suggested using medical benzene and an ear stick or cotton wool .
The benzene sounds a bit harsh to me but i might be wrong , and he has a lot of experience but i am still concerned as this is a special watch and the last thing i want is to damage it in any way .
(I am not going to do it myself , i will leave it to a watchmaker . just wanted to know your thoughts )

cristos71 · Nov 9, 2024

What a great post and fantastic work to figure out all the details of the correct replacement spring. I'm looking forward to seeing it after service.

DirtyDozen12 · Nov 9, 2024

Firstly, thanks for the update on the Valjoux 22 jumper spring. Interesting that the locating pins are not identical but it was still able to fit. Superficially, this is a great result.

Secondly, two good questions re: the crystal, and dial cleaning. I am not certain about either. I am inclined to believe that the crystal could be original, as there appears to be relatively little visual distortion when viewing the dial head on. I would probably leave it on and polish it. As for cleaning an enamel dial, I recently asked the same question after attempting to do it myself with Windex and Q-tips (https://omegaforums.net/threads/cleaning-an-enamel-dial-cyma-with-windex.174953/). Given the rarity of your Longines, I would keep dial cleaning to a minimum in order to avoid any mishaps. I acknowledge that this might be an overly cautious stance given that it is an enamel dial.

1934 40mm Longines Cal 15 chronograph

AdamVT227

DirtyDozen12

AdamVT227

AdamVT227

DirtyDozen12

AdamVT227

DirtyDozen12

AdamVT227

DirtyDozen12

DirtyDozen12

AdamVT227

Radiumpassion

DirtyDozen12

AdamVT227

Larry S

AdamVT227

AdamVT227

AdamVT227

cristos71

DirtyDozen12

Similar threads

Antique 1908 Longines Cal.19.73 pocket chronograph in steel. All original parts. Works perfectly

Lemania Regatta Cal. 1345 with Lobster Bracelet 40mm

Inherited 40mm Seamaster Pre Bond - is this a 1441 or aftermarket movement?

A 1934 tank with center seconds: pilot's watch, Longines medicus, or?

Rolex Submariner Date 16803 - Bluesy - 40mm - R-Serial (excellent / complete)

A wild one… Longines “Coronation” 18.95M