1924 Ladies Round

For its first 25 years Hamilton was known for its pocket watches and being "the watch of Railroad Accuracy".  Wrist watches really didn't become fashionable until after World War I, but ladies models were made with smaller pendant-sized movements.

By the early 1920's, wrist watches were coming into their own.  There were a number of different ladies models presented on ribbon straps as well as detachable leather.  Like the early men's models, the ladies models were defined by their shape; decagon, tonneau, round and cushion.  They came in solid gold as well as gold filled, in white, yellow or green gold.

By the early 1920's Hamilton introduced its only man's strap model, eventually called the Cushion Round, based on the case shape and round bezel opening.  It featured the same 6/0 sized movement used in the ladies model, the 17 jewel 986A.

The 986A is an interesting movement.  It's a bit of a blend of the 17 jewel 986 movement used earlier in ladies pendant watches and the soon to be introduced 987 movement that would come out in 1927.

Unlike the 986 and 987, the 986A does not have a second hand.  However, if it did have one it would have been at the 9 position, like a 986, instead of at the 6 position, like a 987.

I don't particularly like working on watches from the 1920s.  Although they are quality movements, they lack the technological improvements that were eventually added and they tend to have the most "mileage".  In short, they can be worn out and very temperamental.

That said, I'm a little surprised that I haven't already shown a 986A on the blog and I recently had an opportunity after my daughter's watch stopped working.

My project watch is very similar to the one pictured in the catalog, although the dial and hands are different.  This style of hands is called "moon" hands and the crown is an "onion".  My watch is presented on a metal expansion bracelet, which makes it easy to wear.  You'd be hard pressed to find an original ribbon bracelet to mount on it, although I would certainly prefer it.

The inside of the case back is clearly a Hamilton case.  The 25 year warranty indicates it's gold filled.

The 986A movement inside looks more like a 987 than a 986.  I can tell by the markings in the case back that I last worked on this movement in 2012.  So this watch is long overdue for a trip to the spa.

I realized that I don't have a 986A in my "overhaul examples" on one of the blog pages.  If you look at the "Pages" menu on the right side of the blog you'll see Overhaul Examples with detailed step-by-step explanation of the movements I've worked on.  I use this post to document how to assemble the 986A.

As you can see below, everything is taken apart, cleaned in the ultrasonic and dried before being reassembled.

Normally I put the pallet fork on after the train wheels are in place but not on these older movements.  The pallet fork bridge has a screw that is easier to access without the center wheel installed.  So the pallet fork goes on first.

Next the escape wheel and 4th wheel go on.  I carefully position the two wheels so the pallet fork is properly engaged and then the train bridge goes on.

Next to be installed is the mainspring barrel, the third wheel and the center wheel.  Notice it's harder to get to the pallet bridge once these wheels are in place.

The balance cock uses a screw with a smaller head than the other bridge screws... just a little trivia for you.

Once I installed the barrel bridge, the crown wheel and ratchet wheel, I can wind the watch a little and energize the mainspring.  That way once I install the balance, it should start moving.

I noticed the regulator was set to full fast when I first opened the watch.  You can adjust the speed of the balance on these older movements by moving the screws at the end of the balance arm.  Move them out and the speed is slowed, moving them in will speed the watch up.  You need to be very careful with this adjustment though, as you can impact the poising of the movement, not to mention break a balance staff pivot. 

Voila... the watch is back in business and ticking away nicely.  I set the regulator back to the middle to see what's going on.

According to the timer it's looking pretty good.  I can slow it down with the regulator... it certainly didn't need to be set to full fast like it was originally.

Now I can flip the movement over and install the parts on the front of the main plate.

First I'll install the cannon pinion in the center.  This is what the minute hand is attached to.

I need to install the winding pinion and the clutch wheel.  First the winding pinion goes in.

In order to get the clutch wheel in place, I need to remove the set lever spring.

Now I can drop the clutch in place, install the stem, and put the set lever spring back on.

There... getting these parts on can sometimes be a challenge, glad that's finished.

This movement has two gears in the setting portion of the keyless works.  They engage the gold minute wheel.  The minute wheel is driven by the cannon pinion and minute wheel will drive the hour wheel (and hour hand).  That's what keeps the minute hand and hour hand in sync.

The hour wheel goes on and the set bridge... now all I need to do is reinstall the dial.

There are three dial foot screws on the side of the movement that hold the dial in place.  You need to be very careful not to drop the movement, as that's a great way to break the balance staff.

Ta-da!  The movement goes back into the case and this 95 year old watch is ready for more wrist time!

1949 Raymon

Hamilton introduced its first stainless steel wrist watch in 1941 with the Lexington but the material wasn't used that much until 1949 with the introduction of the Clinton and the Raymon.  Stainless steel is a great material for a watch case, it's less expensive than gold or gold filled, it can take a beating and it can be polished back to a nice shiny appearance.  It was used much more frequently after 1950.

The 1949 Raymon was produced for three years and you might say it was a transition model because of the "new" stainless steel case blended with elements of pre-1950 designs likes luminous hands and dials.

The Raymon is a fairly small watch, like most other 1940s model.  Looking at it you might assume it would have a 14/0 sized 980 movement like the Lexington.  In fact, it has the recently introduced 8/0 sized 747 movement crammed into the case.  On the applied gold numeral (AGN) dialed version, the numerals and the hands were rhodium plated to appear silver in color.  The luminous dial had luminous numerals and a special style of luminous hands, unique to this model.

My project watch came as a gift courtesy of a fellow collector.  It had a lot of issues and I'm sure he hoped I could make something of it.  Looking closely at it, I can see the hour hand is the incorrect style, it's missing a second hand, and the crown is quite worn.

As you can see from the side, the crown is showing brass.  I assume the crown wasn't stainless steel but rather white gold filled.

The inside of the case back clearly identifies the model name.  You can see by the number of watchmaker's marks inside that this watch has passed through a lot of peoples' hands.

The movement appears to be in good shape but I'm sure it's been a while since it was last overhauled.

I have found that most Hamilton watches before 1950 have blue steel mainsprings but sometimes I get lucky and find a white alloy Dynavar spring has already been installed.  Not in this case though, there's a blue steel mainspring inside the barrel and it has probably "set" and lost most of its potential energy.

There are two 8/0 sized movements, the 747 and the 748 (or their 1950's replacements the 730 and 735, and 1960's 731 and 736).  Because the movements are quite different, there are several different mainspring strengths to choose from.  Too strong a mainspring will result in too high an amplitude and too low will result in too low an amplitude.  I'll try a standard strength spring, see how it works, and then go from there.

Here you can see the difference between a set blue steel mainspring and a fresh white alloy spring (below).  Notice how the fresh white alloy spring coils so much that it actually goes in the opposite direction.  This will allow the watch to run much longer than the blue steeled version originally installed.

I noticed the upper center wheel jewel in the barrel bridge looked funny and upon close inspection it is cracked.  The center wheel turns so slowly that the crack might not be a big deal but I'll replace it anyway.

Here's an interesting bit of trivia... the serial number for the 747 is on the barrel bridge.  Toward the end of production of the 747 in 1955 the serial number was dropped.  So if you see a 747 without a serial number (or a 748 as well), then you know it's from 1955.  There was no serial numbers on the 730 that replaced the 747 either.  So looking at the barrel bridge on the (left below), it could be from a late 747 or a 730, or even 731.  The parts are otherwise identical but I'll use the one on the right for my replacement.

Everything is cleaned and ready to be reassembled.  I even have a new glass crystal to install.

The reassembled movement is ticking away with good motion.  Let's see what the timer thinks.

The amplitude looks good but the beat error of 4.9ms is above my upper spec of 3.0ms.  The beat error measures how far the balance swings to one side versus the other. The closer to zero the better so I'll have to remove the balance and adjust the position of the hairspring to better center the balance relative to the pallet fork.

Well, I guess I could call that success... it's now below 3.0ms but not by much.  Every time I remove the balance is an opportunity to screw up an otherwise fine hairspring but I will give it one more try.

Okay - nothing to complain about now.   A slight tweak to the regulator will bring the timing down to +/- 30 seconds per day.

I have a new white crown to install as well as a couple of potential second hands.  The second hands are for a 14/0 size movement so the posts are too tight to fit on a 747.  I'll have to open the hole a bit.  The crown has a stylized H on it.  This design was introduced in the mid-late 1950s but Hamilton produced replacement parts for the 8/0 movements with the H logo and there's no real downside to having a crown with an H on a pre-1955 model, other than it just implies the crown is not original.  As long as it fits well and is the correct style, it's really not a big deal.

A pin vise is the best way to secure a stem while you change the crowns.  The old crown should unscrew off and the new crown screws on it's in place.  If the dimensions of the crowns don't match I'll have to replace the stem too but I think they should be okay.

I'll use my set of tiny broaches to carefully enlarge the hole in the second hand so it will fit on the slightly larger pivot of the 4th wheel in the 747.

You can see below that the new crown looks like a great fit.

The finished project turned out great.  The expansion bracelet that came with the watch appears to be a good match, design-wise, but it's not original to the watch.  If you've got a great eye for detail you might suspect this is an older refinished dial, and you'd be correct.  It was redone properly though and it looks just as it should.  The new hour hand is a proper style and looks much better than the previous sword hand, don't you think?

I happened to have a vintage 5/8" grey leather strap, just like this watch would have originally had installed in 1949.  I think it looks much better than the bracelet so I'll keep it like this.

1958 Automatic K-412

It's been a while since I've come across a new Automatic K-series model.  Someday I'll have to make a "most-wanted" list and identify the models that I haven't come across yet.

As fate would have it, I was recently contacted by someone who inherited his grandfather's watch and it serves as a great reminder that all Hamiltons are worthy of being restored, especially family pieces.

The model in question is the K-412.  It was introduced in 1958 and produced for only two years.  It was introduced in the waning years of the K-series and the start of the Accumatic line.  So it could be a fairly rare model.  There are no production records from this time period, unfortunately.

The Automatic K-412 came in a 10K yellow gold filled case and was outfitted with a white dial embossed with yellow markers and numerals.  It also has a pearled minute track with tiny golden dots at each minute position.  Tucked inside the case is a 17 jewel 661 movement.

Check out my project watch below... notice anything unusual?  Where should I start?  The good news is at least it ticks - ha ha!  It has a serious case of dial rash and I don't think I'll be able to do much to improve it.  I could send it out to be refinished but embossed dials with pearled dots are very hard to get done properly.  The figures always seem to come back soft, like they've been over polished.

The gold filled case back is unremarkable and it's loose so I can get it off easily.  These types of cases are very robustly built.

I don't know where the hands went but I can tell you definitively that the second hand is missing because there's no bit to attach it to.  The tip of the 4th wheel is very easy to break off if you're not careful.

The movement appears to be in good shape but it's very dirty.

Although the watch is ticking, that doesn't mean it keeps accurate time.  I rarely check a watch on the timer before I take I work on it... I just assume it's not going to be very good and I'm going to take it apart anyway.  However, just for fun, let's see how this watch is doing?

There is no clear pattern to the trace on the timer although it is moving upward on a steep angle.  According to the sound of the ticking, the timer thinks this watch is running just over 5 minutes fast per day.

I looked in my stash of donor movements and check out what I found!  It's a K-412 dial.  It's not perfect but it's way better than what I started with... plus it has hands.

Here's a picture of the movement's 4th wheel (right) along with a replacement on the left.  Notice the extra portion on the end, called the "bit".  This is what the second hand attaches too.

I think I know which dial I would choose, how about you?  Refinished dials are not a problem with Hamiltons, as long as they are done properly.  That said, a nice original dial is always preferable to a refinished dial.

Everything is ready to be reassembled with fresh lubricants.

The moment of truth has arrived.  The partially reassembled movement is now ticking away with a good motion.  Let's see what the timer thinks of it now.

Well that's much better!  Now it's just a minute fast per day and the amplitude is well over 200 degrees.  The beat error of 0.2ms is right on the money.

A quick adjustment to the regulator index and this watch is now running like it just left the Hamilton factory.

The reinstalled movement is noticeably brighter and shinier than what I started with.

A fresh 28.7mm high dome crystal is definitely called for on this project.  Something needs to keep the hands on, right?

My merciless light tent reveals a little extra tarnish or finish loss on the dial but it looks way better in person.

I also relumed the hands and the dial so it will glow in the dark, when charged first with light.

Here's a wrist shot in more flattering (and realistic) light.  This is a remarkable transformation and I'm sure the owner will be delighted to get his grandfather's watch back.  Now he can enjoy it with pride rather than let it rattle around in a drawer somewhere.