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Caliber 641 (640) - Factory R Gruen Guild

10.5 ligne, 15 jewels; Sat, 01 February 2020 04:08

This caliber appears to have been introduced in 1922, possibly even late 1922. They have pre-1922 tariff markings, but there was a grace period. It’s the only Factory R stamped caliber I’ve seen yet, and the timing would make it one of the later “Factory X” stamps to come into use. But I do find evidence Factory R may have been a Gruen supplier earlier, just didn’t have or use the stamp until 1922. Perhaps a renaming/reorganization—remains to be seen.

These are stamped “640” between plates by the dial screw. All examples I’ve seen are the hunter variant, all marked “641” on the dial back. So they’re stamped for the base 640 open face caliber, the 641 the hunter variant.

Dials are made by Singer SA, all dials bear “107” stamp, which I believe could be Singer’s customer number/reference for Factory R. “107” appears on other much larger Singer dials at this time, too—like the 650. Hope to share an example soon.

Example 1:
Sn (front plate): 11454 (also has a partial “2” stamped to one side)
Markings: 15 jewels, 2 adj. (#s only)

/vgforum/index.php?t=getfile&id=6053&private=0

The caliber database | 14 comments

Caliber 1721 (Gruen Alpina Gilde) - 19’’’

17J, Open Face, Flat hairspring; Sat, 01 February 2020 02:47

Here’s one I hadn’t seen before, I presume one of the “white label” Gruens from the Alpina Gilde days. But could be earlier. Wasn’t sure where to post since it’s not listed in the Gruen material catalogs, but going with the Gruen database since it’s stamped as a Gruen. Pardon the front plate appearance—dial was glued on!! Mad

19 ligne, 17 jewels.

Dr. Ranfft shows the Alpina 1721 is equivalent to the Moeris 19D, so lots of info/details there. His example is listed as 1925, but I think it’s maybe a later version, given the regulator.

He says this movement came in either Breguet or flat hairspring. This Gruen looks to be the flat variant.

/vgforum/index.php?t=getfile&id=6050&private=0

The caliber database | 2 comments

Liberty Khaki Strap Box

1918; Mon, 06 January 2020 18:40

I got this from eBay the other week:
/vgforum/index.php?t=getfile&id=5965&private=0

The strap is also shown in the ad here: http://vintagegruen.org/vgforum/index.php?t=msg&th=343&a mp;a mp;goto=1426&#msg_1426

I'd love to see an original one. I snagged an original WWI strap with the J.F. Sturdy buckle. The site also shows the Gruen "Liberty strap": LINK. I've been able to make reproductions of both. the Gruen one, is far simplier than the others. Seems to be just a simple buckle:

/vgforum/index.php?t=getfile&id=5967&private=0

Anyone have an original?

1910s and prior | 3 comments

Caliber 861 -- Factory L -- and a magic show

6.5'" 16J; Sat, 14 December 2019 19:40

Maker: Factory L
Size: 6.5 ligne
Jewel Markings: 16 Jewels
Adj Markings: 4 Adj
Config: Hunter
Dial feet: 1 & 6.25 positions
Dial release mech: side screws
Example date: late 1922-1923

Sister caliber to the 849. Note the difference in train jewel orientation on back plate, setting bits and layout on front plate. This is a later version, now no longer marked "Gruen Watch Co" or "Gruen Watch Co Factory L" but transitioned to "Gruen Guild". This would be ca. 1923, possibly later 1922. Apologies for the poor quality photos of the back plate, it's currently fully disassembled for service, so can't get better for now.

Note that the machining Gruen did to remove any maker's marks has also totally effaced the Serial Number on this one. A little magic trick happened when I viewed the pic I took at the watchmaker's yesterday--some of the maker's stampings that were machined off the front plate by Gruen partially re-emerged! If you look closely at the front plate pic: by the click spring you can see writing ending in "Co.", and more writing in lower/left center. I assure you, these marks are ground completely away and cannot be seen by the eye or under a loup (I also find evidence of machining down on my 849s). No matter what I did, I could not replicate this. Now you know where to look for any remnants on yours--best of luck! So close to Factory L, but so far!

Any forensic science hobbyists out there? Or any idea of the base metal of these plates? I know there are reagents that can make all these stamps reappear clearly.

/vgforum/index.php?t=getfile&id=5805&private=0

The caliber database | 4 comments

Caliber 849 - 6.5L, 16J - Factory L

6.5'" 16J; Thu, 05 December 2019 03:11

Maker: Factory L
Size: 6.5 ligne
Jewel Markings: 16 Jewels
Adj Markings: 4 Adj
Config: Hunter
Dial feet: 12.5 & 6 positions
Dial release mech: side screws
Example date: your guess as good as mine... 1918-1920?

Other markings: front plate--"27" lot code & "42796" (sn), "Depose"; back of dial engraved "45252"; signed "Gruen Watch Co"

/vgforum/index.php?t=getfile&id=5708&private=0

The caliber database | 18 comments

Caliber 96 (United Watch Co + Gruen Guarantee)

Marc Favre, 10L, OF, 15J; Tue, 03 December 2019 23:47

Maker: Marc Favre
Size: 10 ligne
Config: Open Face
Dial feet: 10.5 & 4.5 positions
Dial release mech: side screws
Example date: ca. 1912
Variants: sister Caliber 97 (possibly hunter config?)

The Caliber date table I've seen lists the introduction date for Caliber 96 as 1917. That is not the case. Here is an early version, made 1912-1913, marked "United W. Co" & "Guarantee Gruen" (transitional, pre-"Gruen Guarantee"). Back plate stamped "Fifteen 15 Jewels", not marked for adjustments. Front plate stamped with lot code "24". Ceramic dial, back marked only "Suisse".

/vgforum/index.php?t=getfile&id=5701&private=0

I've noted later examples, with cases stamped "96", and here is the image from the 1939 parts catalog:

The caliber database | 16 comments

Caliber 626 (& Caliber 101 disambiguation)

8 3/4 Ligne, Hunter - FHF Robert?; Fri, 22 November 2019 14:30

[Rampant edits] Had previously posted this on the sister caliber 103 thread, but I noted the 101/626 had not been documented. Thanks to Liz for help below with disambiguation of the two.

Here is an early WSC variant. 8 3/4 ligne. 16J, 3ADJ. Dial back stamped "101" (dials interchangeable). Front plate has the FHF patent, plus the lot # "17 7577". Could it be the maker was kind enough to mark the make year? "17" = 1917?

Dr. Rannft has cataloged this as the FHF Factory Robert (Gruen Factory R) 8.75'" movement herehttp:// www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2 uswk&Gruen_101. Haven't seen any front plate marks for Factory R, to see if my example matches the style & indicates it was finished there or ebauched to another factory. Most likely sourced directly from FHF/Factory R. Different from the 101, which was sourced as an ebauche from FHF & finished at the Gruen factory (first as regular adjusted, then ca1922 becoming a "precision" caliber)

Caliber 626
Configuration: Hunter
Example date: approx. 1917
Diameter: 8.75 ligne (approx 19.7mm)
Jewel count: 16
Adjustments: 3
Dial feet positions: 10 & 4
Dial release mech: release screws on back plate

/vgforum/index.php?t=getfile&id=5566&private=0

The caliber database | 6 comments

Calibers 794, 794(S), 794(7) -- WSC, Factory F, Guild

Evolution of movements & variants; Tue, 12 November 2019 22:39

(edited to correct "Factory F" to Frey--not Favre Razz )

Size: 10.5 ligne
Config: Open Face
Dial feet: 11 & 5 positions
Dial release mech: friction (no screws)
Variants: 794 (15j, no seconds), 794s (15j, sub-seconds), 7497 (17j, no seconds)

I've just found several variants of this caliber in my collection--all from ca1920 to 1922--thought it might be interesting to see what changed & what didn't. Two are marked "Factory F," and all appear to have been finished by Frey vs. ebauched.

I'm noticing that all "Factory F" marked watches from this period that I own or see on the forum share the same simple stud carrier & click. All mine also have a 6 digit progressive serial number stamped on the front plate by the winding works. May help point out what's Frey finished vs. a Frey ebauche finished at another factory, if others have noticed the same.

They all seem to have 3 adjustments, too...

/vgforum/index.php?t=getfile&id=5487&private=0

201203 - factory F stamped; no caliber # stamped

203644 - factory F stamped; no caliber # stamped; G Pilot Quality 10.5L case # 610367 engraved "1920"

Frey W Co (Delmar): sn 240775, now with 1922 tariff stamps

The caliber database | 2 comments

Caliber 647 (Record)

Tue, 22 October 2019 17:17

You guys are going crazy with a caliber database, so I figured I should try to carry my own weight.

Here's a relatively uncommon one, the 17 jewel Watch Specialties Co. caliber 647. I'm guessing it was in use from the late teens to early twenties. I think my ID as Record 022K is solid. The distinctive bridges and setting parts seem identical to me. The 647 shows up as a movement option for plate 23-B (Strap 1 style) in the 1918 book, but the case is more like the 23-C with conventional lugs.

This example has a serial number of 858749 and in a sterling case with a serial number 567414. I'm guessing the case was Cincinnati made. It doesn't have any Swiss or other markings.

For any further information, I think you can ask timeliz. I'm reasonably confident I sold it to her!

The caliber database | 1 comment

Is this a 1938 Curvex Majesty?

Tue, 22 October 2019 11:45

Good morning to all, I am new here and in the Gruen world. A friend watchmaker has this Gruen Curvex, case 52mm x 22, a very damaged dial, and I was wondering if it is a Majesty or not.
Majesty or not, I would like to hear your thoughts about it
here is a few pic.

1930's | 17 comments

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