I like some of the older models you guys are showing, keep it up!
Me, like I have mentioned, I like the 60 Hour models that are from 1924-1932. This is the end of the Illinois Era, the transition from the sale to Hamilton began in 1928. This was (IMO) the pinnacle of watchmaking in the US before pressed jewels and Swiss movements became the norm.
So let’s talk 60 hour movements.
60 Hour moments came in 3 different jewel configurations, 19j, 21j and 23j all of which were Railroad Approved.
Additionally each jewel type also had variants with in the line. Identified variants are known as Type I, Type II and Type III movements. For both 21 and 23 jeweled movements there are also sub variants of Type IIIa and Type IIIb. Commonly seen as TI, TII, TIII in listings. The differences between these I will show below in 23j versions, same points for 21 and 19j models just different jewel numbers.
The 60hr 23j Type I (TI)
Marked “60” next to “motor barrel” only, no other notations of 60 Hour on the bridge.
The 60hr 23j Type II (TII)
Still has “60” marked by Motor Barrel but now added “60 Hour” above “Bunn Special” on the bridge.
60hr 23j Type III also called TIIIA
This is the last model produced by Illinois before the Hamilton takeover and the most common. “60” mark has been removed from “motor barrel” and is now only on the top of the bridge.
60hr 23j Type IIIb
This is the first Illinois model produced by Hamilton. Looks the same as a TIII except on the bridge where it changes from “Illinois Watch Co” to simply “Illinois Watch” since the Illinois Watch Company no longer existed. This variation is only on 21j and 23j movements as Hamilton discontinued production of and never produced the 19j movement.
There you go, 60hour TI TII and TIII in detail. A long posting but hopefully helpful to someone, somewhere, someday. 11 variants for you to chase down. Happy Hunting!