Internet Horology Club 185
Bad timer results. Watch varies 100+ beats per hour. Figured it out.

This topic can be found at:
https://ihc185.infopop.cc/eve/forums/a/tpc/f/3426047761/m/8213948187

March 10, 2014, 18:56
Paul D. Trombley
Bad timer results. Watch varies 100+ beats per hour. Figured it out.
Bad timer results. What am I looking for? Beat varies 100+ position to position

Repeatable results are horrible:

P1 - 17980bph
P2 - 18030bph
P3 - 17985bph
P4 - 18115bph
P5 - 18025bph
P6 - 18008bph

This is a 5 position watch (was a 5 position watch)

I didn't do anything with the balance assembly when I did the COA... I'm going back in now to polish the pivots and poise the watch and see where that gets me.
March 11, 2014, 14:38
Paul D. Trombley
Grossly out of poise!

- Verified roller jewel centered on pallet fork
- Pulled balance cock assembly
- Pulled the hair spring - inspected sat
- Inspected balance assembly, no noticeable issues
- put on poising tool... grossly heavy on roller jewel side.
- study under 10X magnification...

Roller jewel was replaced in an earlier life. The new jewel is 1.5MM longer than needed... protrudes well above the roller plate... also has excess stickem puddled on the roller plate all the way to the staff.

The correct fix is to restaff the watch, clean the jewel and roller plate, re-size and reset the roller jewel... all outside my experience and tooling at the moment.

Temp fix, mechanically removed as much of the excess stickem as possible. Added a timing washers to the opposite side to poise the balance assembly, ran the timing screws in enough to compensate for the added mass... watch times out nice.