Jump to content

One-button chronograph


Recommended Posts

Hello,

I need input identifying the caliber of a 17 jewel movement. There aren't any markings, and the dial side has minute/ seconds dials at 9 and 3. It is a manual winfing one button chronograpg with brand NIGA on the dial. The balance has a bent pivot and I'd like to get it running again. Thanks for all info.

 

J8a5d351e6720d10217926acb6d4bd85d.jpgd7abc3275d40bd6c8d02619f0d1b13a4.jpg

 

Sent from my SM-J727T using Tapatalk

 

 

Link to comment
Share on other sites

Its a early Landeron Hann I think possibly a calibre 2 but the usual applies photos of the dial side please for positive identification

Is it a 30 minute register or 45 min on the chronograph ?

Edited by wls1971
  • Like 1
Link to comment
Share on other sites

Its a early Landeron Hann I think possibly a calibre 2 but the usual applies photos of the dial side please for positive identification
Is it a 30 minute register or 45 min on the chronograph ?
Sure.

Jda31c16f9acf5ccd181700ce4a31406b.jpg

Sent from my SM-J727T using Tapatalk

  • Like 1
Link to comment
Share on other sites

That's an interesting movement that looks a bit like what you would see in an early 20th century pocket chronograph.  Unfortunately that's like the dark ages where written documentation is hard to come by.

I did a bit of internet scouring and came up with this very brief blog post regarding early Hahn chronographs.  I don't know the calibre but you might find it useful.

https://clocksavant.com/blogs/news/servicing

Link to comment
Share on other sites

Yes @RyMoeller its an early chronograph. It doesn't belong to me, but the owner told me his father "negotiated" it from an Italian pilot during WWII in exchange for not being taken prisoner. I am trying to bring it back to life. The balance staff pivot isbent, but not broken, so I am trying to find a replacement rather than attempting to straighten. Thank you for the material. I have printed it out. I have been able to ascertain that the movement is a Landeron/Hahn...probably cal 2. From there things get confusing because the two balance suppliers I've been able to find use the 15.5 ligne to identify, but they call it different things

http://www.balancestaffs.com/balancestaffs.php

Calls it Landeron(Hahn) 15.5 , staff BS3324

http://www.vintagewatchmarket.com/store.html#!/LANDERON-Hahn-most-calibers-Chronograph-Balance-Staff/p/754166/category=151303

Has TWO 15.5 chrono balance staffs 

Landeron Caliber 46 (15 1/2''') Chronograph Balance Staff (DCN 1001).
Height 468 (contact us if you need the other dimensions).

Landeron 15 1/2''' N (Nouveau) Chronograph Balance Staff (DCN 1000).
Height 467 (contact us if you need the other dimensions)

I also got a quote to machine a new staff from scratch, and it ain't cheap.

I'll post more pictures on this as the project moves forward.

J

Link to comment
Share on other sites

 Here is what it looks like underneath the dial:

DSCN5624.thumb.JPG.10e96ac8debf07bb3091c2d97f2d1c6e.JPG

@wls1971 Can you confirm its a Landeron Hahn? 

Here is what the balance pivot looks like:

DSCN5626.thumb.JPG.0320a4b4e99cc385ed46f6bc1d073e88.JPG

I don't think it can be straightened out,but I'd love input if possible. The darn thing will tick if its dial-down, so probably all else is OK, but I plan to replace the mainspring as well.

J

Link to comment
Share on other sites

Yes its a 15 1/2 ligne 35mm or 16ligne 36mm Landeron/hahn  it looks like the bottom cap jewel for the balance has been replaced could this be the cause of the bent pivot ? 

Edited by wls1971
Link to comment
Share on other sites

6 hours ago, wls1971 said:

Yes its a 15 1/2 ligne 35mm or 16ligne 36mm Landeron/hahn  it looks like the bottom cap jewel for the balance has been replaced could this be the cause of the bent pivot ? 

YEs it noticed that bottom cap as well. Its hard to say if that was the cause, as the caseback has one watchmaker's date to 1951...nothing else. Its fair to say the watch may have been dropped or sustained a strong jolt. I am going to take the measurements of the balance staff that is present, and order a new one. I might try my hand at straightening it. Thanks for your input!

J

Link to comment
Share on other sites



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Two pins or screwdrivers angled out slightly, pressing through from the barrel centre from the opposite side so they contact just clear of the hole in the lid? eg. Strap pin driver needles or similar.
    • That's a good idea - shrinking down the nut and wrench size from the old casebook trick!
    • I missed this earlier. The dial isn't going into the holder, it should sit proud of it. This is what I am currently using which I print for each different movement.    
    • I didn't think pulling to set position would work harden the spring, in that position it is stressed where the arm starts. By work hardening i meant rapid polishing at that point, a bit like polishing a pivot work hardens as it compresses the steel. I doubt polishing by hand would achieve much in that respect though. Its finished, arm polished up mostly at the join to the bridge's main body. I'm ok with it, the screw holes aren't great as i had to open them up by redrilling and positioning it was difficult, I'm not much use with a loupe, opening up with a file might be a better option for me or i could just use the correct drill size 😅. And the detent is way too deep, i had to guess that with the stem release out of position and sat on top, but i only took one measure and went for it, no slowly slowly catch your monkey 😅. First go I'm happy , well sort of, it works and thats a big thing for me, next one will have a bit more finesse.  Anyone thats interested, after filing, i used a 2000 grade home made diamond  micro file and then 20 micron film, the film is much better than wet and dry, more stable to use and doesn't shed cheap grade grit everywhere , then auto polish on a sponge pad.
    • I'm assuming that every time you set the watch you are work hardening the detent spring, maximum hardening is  where it meets the plate due to maximum deflection.   That's why it snaps there.  The Young's modulus may be the same but after it's reached its maximum yeid strength it breaks.  My mechanic engineering is very rusty, correct me if I'm wrong. 
×
×
  • Create New...