| Re: Caliber 615 [message #14358 is a reply to message #14355] |
Fri, 15 January 2021 20:47   |
 |
Case
Messages: 1178
Registered: May 2019
Location: Cincinnati
|
Gruen Authority |
|
|
Adding a few details about this caliber's origin. I think it involves two Biel companies: Aegler & Concord.
The movement is based on a flagship movement for Concord Watch Company (mikrolisk points to Eugene Ducommun-Roulet, then Theodore Schaedeli). But it has unique features, including the bridges. As you will see, it is almost impossible to say who made vs. who finished this caliber, but I am pretty sure it started with Concord and finished at Aegler. This is the first Concord Watch Co base I know of in the Gruen arsenal. Perhaps that is why it is not an 8XX series like other Aeglers--it could also be an Aegler 615, or it could have come first, before caliber #s were shared.
Both makers seem to have been in this serial number range near 1913, when the regulatory marks changed to allow #s only for jewels & adjustments. It is certain that Rolex was sourcing Concord movements for its pocket & wrist watches in lesser sub-brands, but they were also using bespoke variants (presumably finished by Aegler) for the Rolex brand itself.
Here's a link to the base Concord caliber. A later serial number (186k, ca1915-1918), but you can see front plate & slightly different setting bits.
There are 4 features of the 615 I used to conclude Aegler supplied to Gruen:
- the Click - Concord didn't use; Rolex did (example)
- the Serial number - Aegler used a last 4 on front plate; Concord had full serial numbers (see above base caliber link)
- the Bridges - no exact match observed yet; multiple variants in Rolex, Concord always the same
- the Stud carrier - this screw carrier is characteristic on all Concords of this time; Aegler did not use this on Rebbergs movements, but here is a Rolex cased in 1919 with the Concord base, custom finger bridges, the screw carrier--and the hallmark Concord click.
Not totally conclusive, but wanted to share.
My two caveats:
1) I'm wrong many times a day --just ask my wife!
2) Always seeking to learn more
[Updated on: Fri, 15 January 2021 21:03] Report message to a moderator |
|
|
|
Vintage Gruen
Blog
Pages
Search
Help
Members
Register
Login
Home
