1977 Thin-o-matic T-2 something

The last post I did happened to be an early Thin-o-matic model.  By chance, my next project was also a Thin-o-matic, but I think it was a Thin-o-matic in name only.

It's from "the dark ages" of Hamilton watches - the late 1970s, which extended into the 1980s.  A lot was going on during that period and the company that was once the Hamilton Watch Company in Lancaster PA, became the Hamilton Watch Company, a division of whatever holding company owned them, eventually landing on the Swatch Group.  Concurrently, watch technology quickly evolved too and a good portion of Hamilton's model lineup in the 1970s was electronic watches like LEDs and LCD models.

My project watch was an award for an employee of Chevron.  You'll see a lot of watches in the wild with the Chevron logo.  Like Hamilton, Chevron had several predecessors incliding; Star Oil, Pacific Coast, and Standard Oil.

My project is a nice watch, cased in solid 14K yellow gold.  The dial appears to be a classic Hamilton dial, sterling silver with solid gold numerals and markers.  The Chevron logo dominates the top portion of the dial and Hamilton with Thin-o-matic is printed on the bottom half.

Although the dial says Thin-o-matic, this is not a very thin case.  The model number is 978077.  I believe the last two digits are the year of the model.  The case back is engraved with a presentation from 1981 from Standard Oil Company.

The watch opens through the crystal.  Once the crystal is removed, I can lift the dial and movement ou the front.

The case has a deep back, with no mention of Lancaster PA by this time. The number within is unique to this watch and means nothing to anyone other than the case maker, B&A.

The power plant behind the dial is a Hamilton 835 movement.  This is based on an ETA 2871.  I expected to see a white Buren micro-rotor behind the dial, being a Thin-o-matic, but I guess those days were behind them when this watch was made.

The female-side of the two-piece stem looks odd to me, like the old CLD-style female stem.  Turns out it was just loaded with dirt.  Once it was cleaned it looked normal.

By this time period, dial foot screws were replaced my dial clamps, J shaped levers that rotate to pinch the dial feet in place.  Once they are rotated outward, the dial can lift off.

The dial side of the main plate is rather crude looking to my eye... it's sort of Jack Webb of Dragnet theme... "just the facts".  A single screw holds the bridge for the minute wheel and setting wheel.  The ring around the perimeter is a spacer that supports the dial and will lift off.

A single screw holds the oscillating weight in place and once it's out of the way, I can remove the framework that supports it.

At this point this is now just a manual winding watch.  You may be able to see the strong family resemblance between this movement and the earlier ETA calibers like the 688.  There are some differences, of course, but the basics are all the same.

The case has short lugs and will benefit from curved spring bars when it's time to mount a strap.

Everything is cleaned and ready to be reassembled.  I found the little bent golden wire at the top in my cleaning solution... I wonder where it goes?

Aha!  It took me a while but I realized that the bent wire was part of the click that enables winding.  This movement uses an integrated click and spring and the spring part broke off.  Fortunately I have a donor part to use.  You can see on the left what it's supposed to look like.

With a functioning click, I can wind the watch and then install the balance.  It's now ticking away with a brisk motion.  This movement has a 21600 beat per hour rate - a lot faster than the typical 18000 BPH rate of most vintage watches.

Not too shabby.  I can slow it down easily enough.

And voila!  The movement is now running right on the money.

A new crystal and a fresh strap complete the restoration of this elegant almost 50 year old watch.  I relumed the hands and dial so it will glow in the dark again too.  Looks pretty good, don't you think?

1960 Thin-o-matic T-502

There was a time when my least favorite Hamilton models was anything in the Thin-o-matic line.  It wasn't a particularly long time, and it was mainly because I found the microrotor movements to be very challenging to work on.  I ruined quite a few learning the tricks of the trade.  There's a lot tucked into a fairly compact movement, and you have to be very careful during reassembly.

There are at least 57 different Thin-o-matic models, if you include the TM-line.  The list grows to 85 if you included the Dateline models with a calendar complications.  They're actually great models - just a bit more complicated than traditional manual winding movements.

Thin-o-matics actually come in three flavors.  The first is the pink microrotor calibers that were produced by Buren.  Most of the Thin-o-matics fall into this group.  A smaller group of Thin-o-matics featured ETA movements that were similar to the Accumatic line, just a lot thinner.  The third group is the TM line with silver colored microrotors.

One of the earliest Thin-o-matics was the T-502.  It was the third stainless steel Thin-o-matic and followed the 1959 T-500 and T-501.  The T-502 is unique in that it has a grey colored textured dial that looks like linen.

The T-502 was made through 1965 but the last two years is was the T-502B.  Hamilton used the B nomenclature when there was a change in movement that required a different case design, even though the outside of the watch looked the same.  I'm not sure what changed with the T-502B but I suspect perhaps it opens through the crystal while the original has a two-piece case.

My project watch arrived in "as found in a drawer" condition.  It's pretty beat up and it's missing the crown - a classic sign that the watch opens through the crystal.  Could this be the elusive T-502B?

I had to look really hard at the back of the case.  I don't see a pronounced lip, indicating the back snaps on.  However, it doesn't look entirely like a one-piece case either.

I took bracelet off and could make out a little slit between the lugs that I could fit my case knife into.

With a crisp "snap" the case back popped off.  So this is a regular T-502 as far as I can say.  It even has the classic microrotor drag mark inside the case back from the oscillating weight spinning around.

I don't think this movement is installed correctly... it has two case braces but they are on top of a spring ring that surrounds the movement.  I think the braces should go under the ring.

The two braces are removed, as well as the ring.  Then the movement can be lifted out of the case.  You can see the crown is missing because the stem rusted off.

The dial is in decent shape.  It would be impossible to get refinished properly so I will just leave it as is.  I can clean up the hands at least.

Now that the dial and hands are removed, I can start stripping the parts from the movement.

While the parts are in the ultrasonic, I'll turn my attention to the old Speidel bracelet.  The owner asked me to see if I could clean it up, as it has sentimental value to them.  The bracelet is a calendar design with a little scroll that can be moved through a window to show the month desired - in this case, it was August 1971.  The first step is to remove the dirt and DNA that has accumulated over the last 50 years. 

One cleaning session and two rinses later, and the movement is now sparkling clean.  I also replaced the crystal and gasket in the case back.

The movement is almost back together.  The balance is ticking away but I still have to put the balance jewels back in.  This movement had two odd-ball screws from a prior watchmaker.  I replaced those with the correct screws from a donor movement.

The movement is running nicely!  The beat error is just within my personal specs of 3.0ms or less.  It's not an easy adjustment for this movement so I'm glad I can leave it as is.

With the movement sorted out, now I can turn my attention to replacing the stem and installing a new crown.  The stem will need to be trimmed to the correct length to match the placement of the crown on the case stem tube.  It's a little tricky, as if you trim the stem too short, you have to start all over.

Alright, the stem is trimmed, the crown is on, the braces are installed under the spring ring.  Time to close up the case.

The finished watch looks great now - even on the cleaned up Speidel bracelet.  This watch can now spend some time on the wrist and enjoy not be trapped in a drawer somewhere.

1972 Sea Haven III

It's interesting to note that there are almost 50 Sea-somethings in Hamiltons model lineup.  That's about 5% of the men's models but the first Sea-something didn't get introduced until 1957 with the Seabrook.   I don't know what started the trend of naming models with Sea but it continued well into the 1970s.

One of the 1970s models is the 1972 Sea Haven III.  It was produced for two years.  It's unique in that it's one of a small handful of models to feature a blue dial.

The Sea Haven III is unlike it's earlier Sea Haven predecessors.  It's cased in a stainless steel case where the 1964 Sea Haven and 1968 Sea Haven II are cased in 10K yellow rolled gold plate.  The only similarity between the three is they all utilized the same movement.

My project watch was sent to me after the owner said it suffered a hard fall.  Although it still ran, he noted it now had a rattle like something was loose inside the case.  Since it hadn't been serviced recently, he sent it to me to check out.

As received, it doesn't look too bad.  The blue dial is definitely unique.  I think if this was on a blue and white NATO strap it would look pretty cool.  I like the white chapter ring that extends around the inside  perimeter of the crystal.

The case back screws on to the rest of the case.  The model number is 688014-3.  That's interesting, as it gives you a clue to what's inside the case.  The -3 implies a stainless steel case.  If it was -4 it would be yellow gold RGP.  That would be a different model, of course, but the case shape would be similar.

The inside of the case back says Hamilton Watch Co. Swiss.  That's because this watch came from Switzerland, as production in Lancaster ended in 1969.  I see no service marks inside the case back.  I wonder if it's ever been cleaned in 1972.

Inside the case is a Hamilton 61 caliber.  It's hard to see that it also says Hamilton Watch Co and 688.  This is the same movement that was used in the earlier Sea Haven models - although those would say HYL on the balance cock, as that was the import code Hamilton used for their Swiss-made movements.

The good news is there is nothing loose inside the case.  I think the rattling going on was just the assembly held in place by the two case ring braces.  Perhaps they were bent in the fall but there's not a lot of play to them - just a slight amount.  Perhaps it will be fixed when I reassemble it.

At this point everything gets disassembled and thoroughly cleaned.  The 688 is the granddaddy of modern ETA movements.  There have been improvements, of course, and today's beat rate is faster than 18,000 beats per hour, but this movement is otherwise identical to today's manual wind movements.  It doesn't hack though, so that's one major difference, along with beat rate.

Everything goes back together smoothly.  After a few winds to the mainspring, the balance swings back to life.

Not too shabby... the amplitude is a little low but it's not fully wound yet.  The beat rate and error are fine, but I can tweak them with little effort.

I sped it up a smidgeon and reduced the beat error - this is about as good as it gets.

A little Polywatch buffing cleared up the crystal and a new cork strap provides a crisp, but funky, look to this clearly 1970s watch.