Bulova 1921 Rubaiyat

Submitted by jeffreywlee on December 29, 2017 - 8:56am
Manufacture Year
1921
Movement Jewels
17
Movement Serial No.
122147
Case Serial No.
1054041
Case shape
Round
Case color
Yellow
Case Manufacturer
American Standard
Gender
Mens
Watch Description

Hello everyone. This is my first post so please bear with me...

I picked up this Rubaiyat pocket watch a few weeks ago and was hoping you could help me identify some more information about it. I believe it was manufactured between 1919-1921 based on the markings throughout the piece. Here is what I know:

  • Case Measurements: 42.95mm from 9-3 & 12-6, 50.24mm from 6-crown
  • Case Inscriptions: These are all inside the case... American Standard (with Globe), 25 Years, 14K Gold Filled, Monogram Quality, 1054041 (serial number?), there are also 4 scratched inscriptions on the inside of the case - 47123W, X46926, 19826W, L12129... The letters EGS are inscribed on the back of the case.
  • Movement Inscriptions: BULOVA W.Co, 17 Jewels, 5 Adjustments, Swiss, 122147 (Movement SN?), under the movement (behind the dial at the 9 & 8 position) there is an inscription of 1213982

That's all I know. The pictures I am posting below are exactly as I received it. I really want to restore this watch and get it functioning properly. I am fairly handy so I would love to do the work myself but I want your opinions before I really start digging into it. In case you didn't notice from the pictures, the glass is also missing.

Regards,

Jeff

Bulova Rubaiyat
1921 Bulova watch
1921 Bulova watch
1921 Bulova watch
1921 Bulova watch
Reverend Rob
Posted January 2, 2018 - 10:50am

The Balance wheel is the oscillator, which rotates back and forth (in this case) at 18,000 alternances per hour, allowing the mainspring to unwind. The Mainspring transmits its power through the train to the balance, and the centre wheel here turns the cannon pinion on the dial side, which moves the motion works which hold the hands on the Cannon Pinion (Miniute) and Hour (Hour Wheel). The long pivot of the forth wheel carries the Second hand. This is a lever escapement, with ruby pallet stones that lock and unlock the Escape Wheel with each swing. A tiny ruby pin (Impulse or Roller Pin) in the roller table of the Balance flicks the end of the Pallet Fork back and forth as the balance oscillates. 

The Balance oscillates by way of the Hairspring, a precisely measured and tuned spring which allows for precise adjustment of the rate by passing through two regulating pins on the balance bridge top. Moving these pins via the micrometric regulator on your watch, changes the theoretical length of the hairspring to affect the rate. The Hairspring on this watch is a Breguet Overcoil style. 

This type of oscillator has been in use for hundreds of years, and was replaced by another type in 1960, the Hetzl 'Tuning Fork' we see in the Accutrons, and later the Quartz crystal types that caused the 'Quartz Crisis' in the 70's. 

 

Reverend Rob
Posted January 2, 2018 - 10:55am

I should add that there is no shock system on these old balances, and the sheer mass of many pocket watches means that when you drop them, chances are, there will be significant damage to the mechanism, especially the balance. If you pick up a pocket watch and look at the balance and it is dead and not moving, but seems loose in the setting, chances are the staff is broken, a very common problem. 

For the purposes of collecting, you may want to walk away from such a watch, unless it is very special or you are looking for parts. Staff replacement isn't cheap, and it is better to start with a running watch.

jeffreywlee
Posted January 2, 2018 - 5:21pm

In reply to by Reverend Rob

Luckily this one is working... Not sure how well, but it IS running. Thank you for explaining that to me though. I will be sure to stay clear of these and just stick to my little wrist clocks for now :)

Reverend Rob
Posted January 3, 2018 - 2:04am

In reply to by jeffreywlee

I should clarify- I meant walk away only if the staff is broken. These watches are getting rare and running versions are certainly worth collecting. If you see any more like this and the balance is ok, it is very much a collector's piece. As with all non-shock watches, careful handling is all that is needed.