Internet Horology Club 185
Bunn Spec. 161A

This topic can be found at:
https://ihc185.infopop.cc/eve/forums/a/tpc/f/1086047761/m/3141065392

December 06, 2007, 13:21
Jerry Freedman
Bunn Spec. 161A
Here is another oddball. I am assuming this is a case of a balance cock switch If not, I have a very rare watch. The movement number is 5569289.
I have never seen one with Elinvar in two places.


December 06, 2007, 14:10
Mark Cross
Jerry, just as an aside, do you have any idea at what serial number Illinois started installing the Elinvar hairsprings in the Bunn Specials?

Regards! Mark
December 07, 2007, 15:58
Russ Snyder
According to Illinois records, the first appearance was in 1929 on 161E Model 14 in production run 5,282,001 - 5,282,100. There was another run of 300 161E later that year.

The first 163E (Model 15) appeared two years later in 1931 with the run 5,420,301 - 5,420,600.

Thereafter there were numerous runs in the 1930's

Russ Snyder
December 07, 2007, 16:00
Russ Snyder
I should have prefaced my comments by stating that these were the first models MARKED with "Elinvar". That is not to suggest that Illinois didn't employ the use of the Elinvar hairsping prior to this, but without DESIGNATING this with the marking.

Russ
December 07, 2007, 17:00
Jim Carroll
Jerry,
As the run is from 5,568,001 -5,570,000 here is some other movements from that run.
P.S I don't own these movements.


Jim Carroll


December 07, 2007, 17:05
Bill Kapp
Jerry,

Not my specialty, but the damasceening doesn't seem right on your balance cock either.

Bill