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Sunday, January 18, 2015

WWII USMC Aviators Watch

Hamilton made a variety of military watches during World War II.  In fact, during the years 1942 through 1945 virtually all production was dedicated to the war effort.

The most commonly found military watch is the US Army version with the white dial and a case back engraved with "ORD DEPT".  At any given time there are several of them for sale online.

Hamilton also made watches for the US Navy and Marine Corps.  These watches come in different cases and are engraved on the back with HAMILTON WATCH COMPANY along with the part number that is unique to each watch version.  You can read more about it on this thread.

Among the scarcest are the FSSC 88-W-800 watches, and part number 39102, specifically.  Only 2,926 of these watches were produced for the US Marine Corps, and they were specifically made for aviators.


A number of things make the 39102 version unique.  First of all, it features Hamilton's first 18 jewel sweep second movement... the 2987.  Like the 987S, the 2987 is a hacking watch so the watch will stop when you pull out the crown to set the time.

The watch also features a Wadsworth case - while other military watches were either Star cases or Keystone cases.

I recently scored a 39102 USMC watch and it proved to be a true labor of love.  It arrived as non running but, as you'll see below, it had several issues, any one of which would cause it to stop running.

First off though, you'll note this watch has a black dial.  The US Navy version received a black dial and the USMC version was white.  Naval aviators had a 2987-based watch too though. However, the Navy version came in a Star case with part number 39103 on the back.  You can read more about the US Navy version here.  So this dial is a replacement.


The Wadsworth case should be stamped with a W in between the top lugs, as shown below.


Here's a shot of the case back engraving.  Although the bezel is chrome plated brass, the back is stainless steel.  The back unscrews using a large combination wrench, nothing much to it.


Under the case back you should see a dust cover that snaps onto the movement ring that surrounds the movement inside.


And here's the 2987 movement.  It looks a lot like the 987S, which was also used for military watches.  However, the 2987 adds an extra jewel to support the second hand pinion in the center.  The pinion is also supported by a spring, partly visible under the sweep second wheel.


Winding the watch, I realized the mainspring was broken... as I could wind and wind and wind it without ever hitting resistance and stopping.  So that's one reason why the watch isn't running.  I also noticed the hairspring is a skewed off to the side (toward the balance cock).  That's another reason why the watch was dead on arrival.

The dial has a little bit of rust in the center.  The dial is old and looks like it could be original.  However the mismatched hour and minute hands are not correct for the watch.  The second hand is correct though.  On the black dialed models, the hour and minute hands should technically be stainless steel.  That's an important detail to look for but not a deal breaker.


The crystal that is installed is rather odd.  It has a wide flange so it appears a lot smaller than the bezel opening.  I'll change that out with a proper crystal.


Pulling the gold-colored sweep wheel is a job for a specialized tool made just for this purpose.  It looks a lot like a Presto-style hand puller but one side is split to go over a wheel spoke while the other grasps the hub.


Squeezing the tool will lift the wheel straight up and off so you don't bend the extended third wheel pivot.  Once I got the sweep wheel off, I removed the sweep pinion bridge.  However, I couldn't get the sweep pinion itself out.  It was rusted to the inside of the center wheel.  Eventually I worked it loose and I then ran tiny broach through the inside of the center wheel to open it back up again.  A seized seconds pinion would definitely stop the watch from running.


Once I got the wheels out, I noticed the hack spring had been bent out of the way.  Although it still moved when the stem was pulled out, it was not in the right position to stop the watch.  So I had to rebend it back to the proper shape.

While everything is in the ultrasonic, I'll replace the crystal with a PHD high dome crystal.


That looks much better than the wide-flanged crystal.


I'll prep a new white alloy mainspring for the movement too.


Close inspection of each jewel revealed that the center wheel jewel in the barrel bridge is cracked.  It's the larger of the two jewels below.  The jewel is larger than a 987A's center wheel jewel but it's the same size as a 987S and I happen have a parts watch to use as a donor.


The jewels are held in place with friction and are removed and reinstalled using a staking set and a flat punch.  It's best to replace cracked jewels if you can, as they are a source of friction and wear.


All of the parts are now cleaned, including two potential balance wheels.


While reassembling the watch, I found out the pallet fork arbor was missing a pivot - so that's yet another reason why the watch would not run.  I think I'm up to four different reasons for why this watch movement wouldn't run.

In the end, without the seconds sweep wheel or pinion installed, this movement looks like a regular old 987A.  It's back to running condition now thanks to a new pallet fork, a new mainspring, a new center wheel jewel and a new balance assembly.


Well, it's running alright and dead on from a beat rate standpoint.  The beat error is within acceptable tolerance.  The amplitude is well over 200 degrees so there's a lot of energy in the watch.  The reason the two lines are so far apart is the lower line is on the top of the screen and the upper line is just above the bottom of the screen.  So they're actually much closer than they appear.


I happened to have a spare white dial and hand set up so the finishing touches to this restoration are the dial, hands and a new canvas strap.  It's back to looking just as it would have in 1943.


And here's a final shot of the case back.  This is one mighty rare watch.  I was lucky to find it.  With less than 3,000 made and the rest going into harm's way, I wonder how many are still in existence?  I'm glad I was able to get this one back into wrist-worthy condition.


14 comments:

  1. Amazing job on a fantastic looking watch!

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  2. This is amazing... I may be getting my hands on one of these, but with a small seconds sub-dial at 6 o'clock... do you know if that one is as rare?

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    1. There are lots of military watches and versions with the small seconds hand at 6 on a white dial are the most common. Case maker and the movement inside is important, as they can get mixed around and not be correct. For example, the watch above should have a 2987 and not a 987S or a 987A. Other cases should have those movements though.

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  3. I have this watch however what are my chances of either finding an original case or restoring the case?

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    1. Your chances increase in direct proportion to the amount of money you have.

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  4. I have recently inherited a 39102 watch from my father who was a USN aviator in the pacific during WW2 (black dial and marked 39102 with W on case so the 39102 was not just a Marine Corp watch). This watch is completely original and has been stored in a drawer since 1945. Its not in bad shape considering its age, it still winds and works but the second hand does not stop when pulling out the crown. The crystal is faded and discolored and the minute/hour hands have rusted, Obviously, the watch has much sentimental value and I would like to have it repaired/restored. I also have the original aircraft clock from his USN plane (Waltham 8 day/15 jewel, Civil Date that is over wound and stcuk that I would also like repaired/restored), Do you have any suggested as to someone who is reputable with expertise in restoring/repairing these particular Hamilton watches and Waltham clocks (and also maybe have some spare parts) in their inventory? If so, could you make some recommendations?

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    1. I have seen enough 39102s with original black dials that I suspect they came with black or white dials. That may just imply that Marine naval aviators got white dialed 39102s and Navy naval aviators got black versions or 39103s. Regardless, it's a cool heirloom nonetheless. It should hack so the spring inside is either missing or misshaped.

      Any watchmaker worth his salt should be able to tackle a vintage Hamilton. The 2987 is very similar to a 987S and shares most parts but not all of them. If you email me I will give you some recommendations.

      The Waltham 8-Day clock is a neat keepsake too. "Over wound" is a term used to describe a fully wound but non-running watch. It's probably not truly over wound, it just doesn't run. Again, any competent watchmaker can diagnose it. It's basically a big ol' pocketwatch with two mainspring barrels. Contact Historic Aviation Supply if you want to send it their way. https://historicaviationsupply.com/

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    2. I recently picked up a 2987 Hamilton but it has a Waltham dial. Are replacement dials available?

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    3. Probably easier to get the dial and hands refinished.

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  5. Great article HandyDan!
    I know this is an old thread... I have restored a number of Waltham A-11's, but I have never found a single Hamilton 2987 to restore.
    I do have a nice 987s watch that I recieved as a gift from another watch nut friend of mine...he also gave me a set of NOS 2987 hands - for that future project...
    The only flaw I can see with these 6/0 military watches is their size - They would be even better if they were just a little bit bigger...
    In any case, I am sure you know already, but if you're patient, you can tighten up that beat error - just by moving turning the hairspring collet a bit.

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    1. Oh yeah, sometimes I'm appalled at my oldest posts because the beat errors are a wee bit high. Adjusting these movements isn't too hard but the older ones (pre-1940) can be very finicky. I'll often settle for a beat error under 3.0ms rather than roll the dice and screw up an otherwise good hairspring. 2.5 is on the high side of acceptable in my book but I usually try to get it under 1.0.

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  6. Hi, I have one of the white faced USMC watches in my sights right now, can you tell me if all these had the Wadsworth case (is the name inside the case back?

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  7. Can anyone tell me what Marine grunts would have wore in WWII? Because that’s the watch I want

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  8. Hi all,
    I have a black dial 2987 with 3S2894 movement number in great condition and bought it 30 years ago in London. I am pretty sure my matching hands are original as they fit the watch dial perfectly with enamel like luminous paint BUT their shape is diamond (hour) and fine pointer (minute), not spade or mercedes. Does anyone have similar. Cheers, Pete

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