Jump to content

Hamilton 992 movement seconds wheel (forth wheel) needed


jdrichard

Recommended Posts

Does anyone have a Hamilton 992 movement seconds wheel (forth wheel)? Mine has a broken pivot that I may not be able to repair.a60a42668bb994dcfac0c9596244fe37.jpgThis is before I failed at straightening it and it snapped. Going to try to repivot it but may be completely unsuccessful.

 

 

Sent from my iPhone using Tapatalk Pro

Link to comment
Share on other sites

New evil plan. I will create a sheath over the broken shaft and pivot by drilling a hole in a piece of blued steel, just smaller than the shaft. Then I will friction fit the shaft inside the new steel part. Then I will grave down the long pivot to .24mm for the second hand pivot. 518a0d5713ca61e447bdb2d96919986c.jpg


Sent from my iPhone using Tapatalk Pro

  • Like 2
Link to comment
Share on other sites

I always liked those pre 992B 992 movements, especially the ones with the concentric rings on the winding wheels. I don't know why I like those so well, I just do. I don't own one, but I like them. Congrat's on getting it up and running with the JD-pivot.

Link to comment
Share on other sites



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • 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. 
    • Ah ok yes that makes sense to polish it where the arm starts to form from the body of the bridge, i thought you meant the underneath of all the arm.
    • this is something I've never quite understood about the some of the Swiss companies. In 1957 Omega was using 9010 for the keyless parts with epilam. there's been a slow migration towards using heavier lubrication's but still typically oils and epilam to keep them in place. When it seems like 9504 works so much better.  
    • OK, welcome in the world of alarm clocks... I guess the 4th wheel is dished because it is from another movement. If it was not dishet, then it would not mesh with the pinion of the escape wheel, am I right? The marks of wear on the 4th wheel pinion doesn't corespond to the 3th wheel table position, at list this is what i see on the picts. Calculating the rate is easy - there is a formula - BR = T2 x T3 x T4 x T5 x 2 /(P3 x P4 x P5) where T2 - T5 are the counts of the teeth of the wheels tables, and P3 - P5 are the counts of the pinion leaves. Vibrating the balance is easy - grasp for the hairspring where it should stay in the regulator with tweasers, let the balance hang on the hairspring while the downside staff tip rests on glass surface. Then make the balance oscillate and use timer to measure the time for let say 50 oscillations, or count the oscillations for let say 30 seconds. You must do the free oscillations test to check the balance staff tips and the cone cup bearings for wear. This kind of staffs wear and need resharpening to restore the normal function of the balance.
    • Glue a nut to the barrel lid, insert a bolt, pull, disolve the glue.  Maybe someone will have a better answer. 
×
×
  • Create New...