1923 Ladies Decagon

Long before there were men's wrist watches there were ladies wrist watches.  Men of distinction would wear a pocket watch.  I guess the trenches of WWI proved that real men could wear wrist watches and by the early 1920s you could find men's and ladies models in Hamilton's line up.

Ladies watches came in two forms, the earliest being essentially small open-faced 6/0 sized pocket watches on a chain bracelet.  The other were 6/0 movements without a second hand in a case that would be outfitted with a silk ribbon strap.  It's very unusual to come by an original strap with its original buckle (findings).  You'll see them on rare occasions but they are always in tatters.

The cases for Ladies models with ribbon straps were highly engraved.  The also came in different shapes... round tonneau, cushion, and 10 sided decagons.  Cases were offered in solid gold and gold filled.  You had lot to choose from!  

My project watch dates to 1923, 101 years old.  Looking at the loops for the strap, there have obviously been some repairs.  However, there's not a lot of case wear, considering it's a gold filled case.

The trick with these three-piece cases is to find the right spot to slip a case knife in to remove the back and the front bezel.  This case back has a clue to which corner, as it's a bit chewed up from prior openings.

Tucked inside the case is a 17 jewel 986 movement.  This watch is fully wound but not running.  There's no obvious issue, like a wobbly balance, so hopefully a good cleaning is all that is needed.  We'll see.

This caliber shares a lot of parts with what would soon be introduced as the 987 movement, but it would be a few more years for the 987 to be hit the catalogs.  Notice the case back has a hole in one of the corners - this hole aligns with a post in the case and helps you align the 10 sides when you press it together.

The mainspring inside is an old blue steel design.  I have no doubt that it will be "set" in a coil and need to be replaced.

Sure enough, not only is it a tight coil, notice it isn't flat - this is a sign that it was installed by hand.  That's a very tedious process and a mainspring winding tool is a much better process.   This mains also has a Swiss-style brace at the outer end.  In order to use this spring, a small metal rod was installed in the barrel, to catch the brace and keep the spring from spinning.  This isn't a proper Hamilton mainspring with a T end, so I'll replace it for sure.

Everything gets cleaned and dried.  I installed a fresh white alloy mainspring for a 987 movement.  It should be okay as the 986 shares the same mainspring as a 987.

Although my camera has frozen the motion in time, the movement is now ticking away with a good motion.  Let's see what the timer has to say.

Hmmm... something is making extra noise inside.  The timer listens to the ticking and discerns how it's running.  It's picking up extra noise and it could be the hairspring is rubbing the center wheel or there's a piece of dust inside.  It doesn't take much to send the timing off.

It took some tweaking but I got the hairspring to run cleanly.  The amplitude is great, the beat error is a little high.  The two lines are little wobbly.  It could be one of the wheels is a little worn or bent - after 100 years a lot can happen to a watch.  It would take some detailed analysis to find the issue.  The beat error could be reduced if I had the cajones to try.  Balances from this era of watches have no forgiveness and are extremely easy to goof up.  As they say in every Star Wars movie - "I've got a bad feeling about this" and I'm going to listen to my inner voice and let sleeping dogs lie.  This beat error isn't ridiculously high so I don't feel bad leaving it as is.

The cleaned case is bright and shiny so this 100 year old watch looks fantastic.  I was unable to bend the lug loops... whatever material was used to repair them is definitely solid.  A jeweler could probably straighten them and prep them for a new strap.