I know it is difficult to answer a "why not" question, but... Since the Sangamo Special was supposedly Illinois' highest grade railroad watch, why did the Illinois (or Hamilton) company use the Elinvar balance on the Bunn Special and not the Sangamo Special? Had they discontinued making the Sangamo Special by that time? And wasn't this some time before using it on the Hamilton watches? Why was it used first on the Illinois models? I hope someone could clarify this for me.
Thanks

Stephen,

I can tell you the last Sangamo was made in 1927, the year before Illinois was sold to Hamilton. They continued making watches in Springfield until 1933 when the contents of the plant were moved to Lancaster, PA. I can also tell you that the Elinvar balance first appeared in 1931 on the 161 and 163's but I can't tell you when they showed up on the Hamiltons. My guess would be that they appeared about the same time on both watches but we will need a Hamilton expert to jump in.

Steve

When Lin sold an Elinvar equipped S.S. last year, it raised a real firestorm kindled by some of our ex-members. It all has to do with how Hamilton was trying to deal with "depression" inventory. Quite a story read it all at;

https://ihc185.infopop.cc/eve/forums/a/tpc/f/3426021842/m/4231015382

Thanks very much! I don't know, but I was told some years ago that Hamilton first used the Elinvar balance on their 4992B during the war, and later on the 992B. If so, they used it on the Illinois several years earlier. I would like to know more about the whys and wherefores of that, too.

I found an article in the NAWCC Bulleting of Februaru 1996 by Dewey Clark, titled "Balance Assemblies: Principles of Operation and a Little History." Mr. Clark gave a thorough description of the invention and use of Elinvar by Dr. Guillaume, who was the director of the Bureau of Standards when he invented the alloy. He stated that Hamilton bought the right to use Elinvar and began using it in 1931 in both the 992E and the Bunn Special. Very interesting stuff. He also described the technical evolution of the marine chronometer.

I am planning to join. I think this is a great source! At the risk of appearing cheap, I'm waiting for the new price guide to come out, since I already have the 2008 edition. Thanks so much for your help!