1935 Hamilton Seckron

One of the more interesting watches from the 1930's is the 1935 Seckron, marketed as a doctor's or nurse's watch because it had a prominent second hand.  It's a very unusual watch because it uses a variant of the 14/0 sized movement that was released in 1935 - the 980 movement.

What makes the movement unusual is the hour and minute hands are off set such that there are two registers for time... one for hour and minute and the other for seconds.

The Seckron was cased in 14K gold filled and produced from 1935 to 1939.  It was continued in 1940 and 1941 but with an entirely different case.  It's interesting that the second version wasn't named something like Seckron II, or even a Seckron B.

The early Seckron was available with either a white dial with black enamel or a black dial with white enamel.

For the first two years the Seckron was powered by a 980A movement.  In 1938 the movement evolved into a 980B.  The main differences are how the hour and minute hands are offset using several additional wheels.  This price for the Seckron stayed the same until the 1940 version came out - it was a little less expensive, thanks to the case material changing to 10K gold filled.

Personally I think the 1940 version is a little more attractive - it has a slightly sleeker, more elegant case.

My project watch is in excellent condition, at least for this model.  More often than not, the case on the Seckron shows extensive wear through.  The dial on this example is a bit dirty and the second hand is an obvious replacement but once it's cleaned up, I bet it will look much nicer.

Typically you will see some wear thru on the corners of the case back... this one looks fantastic, but it does have some wear to the lip near the lug used for opening the case.

The case on the Seckron is rather thick by comparison to other models.  That's to accommodate the extra layer of parts on the front of the main plate.

The 980A has a serial number that starts with G, just like the regular 980 movement.  For the most part, from the back, the movements are identical.  It's only the dial side that makes the 980A stand out.

The dial is held in place with two dial feet but they're a little longer than typical so they can pass through the spacer plate.

Here's a shot of the dial side of the movement and you can see the extra set of wheels needed to move the hour and minute hands upward.  The center wheel that typically drives the minute hand is still in the center but the cannon pinion is shortened and has two sets of geared teeth.  One for the setting mechanism, and the other to drive the extra wheels.  A long spring arm secures the extra wheels in place.

Notice this movement shows a lot of rust.  Most of that will come off in the cleaner but it's a good thing this watch is getting overhauled.  Rust and watches do not get along.

Just for comparison's sake, here's the dial-side of a 980B.  Notice it's quite different.   You don't want to lose or have to replace any of these parts - that's for sure.  They are very hard to come by.

I don't often explain my work setup.  I clean parts using three jars that go into a water bath in my ultrasonic cleaner.  One jar has cleaning solution and the other two have a rinse solution.  Each jar gets 7 minutes in the water bath.  When I move the parts from jar to jar I run a small desktop fume hood to draw the fumes through a set of filters so my nose isn't sniffing them up the whole time.   This little fume hood is awesome and was a great addition to my setup. 

With parts stripped off the front, I can turn my attention to the rear of the movement.  Piece by piece, everything will go into the cleaning jar.

The barrel already has a white alloy mainspring so there's no need to replace it.

While all the parts are being cleaned I will install a new glass crystal and put it out in the sunshine so light will cure the UV glue.

Okay... everything has been cleaned and is ready to be reassembled.

The reassembled movement is noticeably brighter now.  The balance is ticking away with a good motion - that's a good sign.

It's running a smidge fast but that should be easy to adjust.  The amplitude and beat error are well within specs.

There... I'll leave it running 12 seconds fast per day.  Not too shabby for a 90 year old watch.

With the movement running fine now, I can turn my attention to reassembling the dial-side components.  The only thing left is the dial and hands.

A new glass crystal is a huge improvement over what I started with.  The dial is what it is after so many years.  I think it looks great.  The second hand could stand to be a little longer but you can get the gist.